WO2009158719A2

WO2009158719A2 - Methods and compositions for treating disorders

Info

Publication number: WO2009158719A2
Application number: PCT/US2009/049106
Authority: WO
Inventors: Magdalene M. Moran; Howard Ng; Amy Ripka; Manfred Weigele; Dennis Underwood
Original assignee: Hydra Biosciences LLC
Current assignee: Hydra Biosciences LLC
Priority date: 2008-06-27
Filing date: 2009-06-29
Publication date: 2009-12-30
Anticipated expiration: 2010-12-27
Also published as: WO2009158719A3

Abstract

Compounds and compositions for treating TRPA1 mediated disorders are described herein.

Description

Methods and Compositions for Treating Disorders

Claim of Priority

This application claims priority from U.S.S.N. 61/076,444, U.S.S.N. 61/076,309, U.S.S.N. 61/076,402, U.S.S.N. 61/076,406, U.S.S.N. 61/076,409, U.S.S.N. 61/076,411, U.S.S.N. 61/076,441, all filed June 27, 2008 and all of which are incorporated herein by reference in their entirety.

Background A variety of ion channel proteins exist to mediate ion flux across cellular membranes.

The proper expression and function of ion channel proteins is essential for the maintenance of cell function, intracellular communication, and the like. Numerous diseases are the result of misregulation of membrane potential or aberrant calcium handling. Given the central importance of ion channels in modulating membrane potential and ion flux in cells, identification of agents that can promote or inhibit particular ion channels are of great interest as research tools and as possible therapeutic agents.

Summary of the invention

The present invention provides compounds, methods and compositions for treating or preventing conditions such as pain by modulating the activity of the TRPAl channel. The compounds described herein modulate the function of TRPAl by inhibiting a TRPAl -mediated ion flux or by inhibiting the inward current, the outward current, or both currents mediated by TRPAl . The inhibition of a particular current is the ability to inhibit or reduce such current (e.g., inward and/or outward) in an in vitro or an in vivo assay. The following articles are exemplary of the state of the art regarding the structure and function of TRPAl (Jordt et al. (2004) Nature 427:260-265; Bautista et al., (2005) PNAS: 102(34): 12248- 12252). The foregoing articles are incorporated by reference in their entirety.

One aspect of the present invention relates to a method for treating or preventing a condition involving activation of TRPAl or for which reduced TRPAl activity can reduce the severity by administering a TRPAl antagonist that inhibits TRPAl -mediated current and/or TRPAl -mediated ion flux. In certain embodiments, the TRPAl inhibitor is used to treat or ameliorate pain. Exemplary classes of pain that can be treated using a TRPAl inhibitor include, but are not limited to nociceptive pain, inflammatory pain, and neuropathic pain. Pain that can be treated with a TRPAl inhibitor can be chronic or acute.

In certain embodiments, a TRPAl inhibitor used in the treatment of any of the diseases or indications disclosed herein has one or more of the structural or functional characteristics disclosed herein.

In one aspect, the invention features a compound of formula (II), or a pharmaceutically acceptable salt thereof:

Formula (II) wherein,

R^! is Ci-C₆ alky], C₂-C₆ alkenyl, or C₂-C₆ alkynyl, each of which is optionally substituted with 1-

4 R⁵; X is N or CR²

R² is H, Ci-C₆ alkyl, C₂-C₆ alkenyl, or C₂-C₆ alkyny], each of which is optionally substituted with 1-4 R^5';

L is NR⁶SO₂, SO₂NR⁶, OC(O)NR⁶, NR⁶C(O)O, NR⁶C(O)NR⁶, NR⁶C(O), C(O)NR⁶, C(O), O, S,

S(O), S(O)₂, NR⁶, CH₂, cycly], aryl, heterocyclyl, or heteroaryl; R³ is cycly], heterocyclyl, aryl, heteroaryl, each of which is optionally substituted with 1-4 R⁷; each R⁵ and R⁵ is independently halo, hydroxyl, alkoxy, amino, alkylamino, dialkylamino, cyano, nitro, amido, alkylamido, dialkylamido, thioyl, sulfonyl, cyclyl, heterocyclyl, aryl, or heteroaryl; each R⁶ is independently H, Q-C₆ alkyl, arylalkyl, S(O)alkyl, acetyl, amidyl, or S(O)H; each R⁷ is independently CpC₆ alky], C₂-C₆ alkenyl, C₂-C₆ alkynyl, cycly], heterocyclyl, aryl, heteroaryl, halo, hydroxyl, alkoxy, aryloxy, arylalkoxy, amino, akylamino, dialkylamino, thioyl, alkylthioy], sulfonyl, sulfonamidyl, amido, urea, sulfonylurea, hydroxyl alkoxy], alkoxy alkoxy], acyl, nitro, cyano, each of which is optionally substituted with 1-3 R⁸; each R is independently Ci-C₆ alkyl, C₂-C₆ alkenyl, or C₂-C₆ alkynyl, halo, hydroxyl, alkoxy, aryloxy, amino, akylamino, dialkylamino, thioyl, sulfonyl, sulfonamidyl, amido, urea, sulfonylurea acyl, nitro, cyano, cyclyl, heterocyclyl, aryl, or heteroaryl; each m and n are independently 0, 1, 2, 3, 4, 5, or 6, wherein m is at least 2 when L is connected to the methylene carbon via a heteroatom; each R⁹ is independently H, Ci-C₆ alkyl, C₂-C₆ alkenyl, or C₂-C₆ alkynyl, halo, hydroxyl, alkoxy, aryloxy, arylalkoxy, amino, akylamino, dialkylamino, thioyl, alkylthioyl, sulfonyl, sulfonamidyl, amido, urea, sulfonylurea, acyl, nitro, cyano, each of which is optionally substituted with 1-3 R⁸.

In another aspect, the invention features a compound of formula (III), or a pharmaceutically acceptable salt thereof:

Formula (III) wherein, R¹ is C]-C₆ alkyl, C₂-C₆ alkenyl, or C₂-C₆ alkynyl, each of which is optionally substituted with 1-

4 R⁵;

X is N or CR²

R² is H, CpC₆ alkyl, C₂-C₆ alkenyl, or C₂-C₆ alkynyl, each of which is optionally substituted with 1-4 R^5'; L is NR⁶SO₂, SO₂NR⁶, OC(O)NR⁶, NR⁶C(O)O, NR⁶C(O)NR⁶, NR⁶C(O), C(O)NR⁶, O, C(O), S,

S(O), S(O)₂, NR⁶, CH₂, cyclyl, aryl, heterocyclyl, or heteroaryl;

R³ is cyclyl, heterocyclyl, aryl, heteroaryl, each of which is optionally substituted with 1-4 R⁷; each R⁵ and R⁵' is independently halo, hydroxyl, alkoxy, amino, alkylamino, dialkylamino, cyano, nitro, amido, alkylamido, dialkylamido, thioyl, sulfonyl, cycly], heterocyclyl, aryl, or heteroaryl; each R⁶ is independently H, C]-C₆ alkyl, arylalkyl, S(O)alkyl, acetyl, amidyl, or S(O)H; each R⁷ is independently Ci-C₆ alkyl, C₂-C₆ alkenyl, or C₂-C₆ alkynyl, halo, hydroxyl, alkoxy, aryl, heteroaryl, cyclyl, aryloxy, arylalkoxy, amino, akylamino, dialkylamino, thioyl, alkylthioyl, sulfonyl, sulfonamidyl, amido, hydroxyl alkoxyl, alkoxy alkoxyl, urea, sulfonylurea, acyl, nitro, cyano, each of which is optionally substituted with 1-3 R⁸; each R⁸ is independently Ci-C₆ alkyl, C₂-C₆ alkenyl, or C₂-C₆ alkynyl, halo, hydroxyl, alkoxy, aryloxy, amino, akylamino, dialkylamino, thioyl, sulfonyl, sulfonamidyl, amido, urea, sulfonylurea acyl, nitro, cyano, cyclyl, heterocyclyl, aryl, or heteroaryl; each R⁹ is independently H, C]-C₆ alkyl, C₂-C₆ alkenyl, or C₂-C₆ alkynyl, halo, hydroxyl, alkoxy, aryloxy, arylalkoxy, amino, akylamino, dialkylamino, thioyl, alkylthioyl, sulfonyl, sulfonamidyl, amido, urea, sulfonylurea, acyl, nitro, cyano, each of which is optionally substituted with 1-3 R ; each m and n are independently 0, 1, 2, 3, 4, 5, or 6.

In another aspect, the invention features a compound of formula (IV), or a pharmaceutically acceptable salt thereof:

Formula (IV) wherein,

R¹ and R² are each independently Cj-C₆ alkyl, C₂-C₆ alkenyl, or C₂-C₆ alkynyl, each of which is optionally substituted with 1-4 R⁵;

L is is NR⁶SO₂, SO₂NR⁶, OC(O)NR⁶, NR⁶C(O)O, NR⁶C(O)NR⁶, NR⁶C(O), C(O)NR⁶, O, C(O), S, S(O), S(O)₂, NR⁶, CH₂, cyclyl, aryl, heterocyclyl, or heteroaryl;

R³ is cycly], heterocyclyl, aryl, heteroaryl, each of which is optionally substituted with 1-4 R⁷; each R⁵ is independently halo, hydroxyl, alkoxy, amino, alkylamino, dialkylamino, cyano, nitro, amido, alkylamido, dialkylamido, thioyl, sulfonyl, cycly], heterocyclyl, aryl, or heteroaryl; each R⁶ is independently H, CpC₆ alky], arylalkyl. S(O)alkyl, acetyl, amidyl, or S(O)H; each R⁷ is independently Cj-C₆ alky], C₂-C₆ alkenyl, C₂-C₆ alkynyl, cycly], heterocyclyl, aryl, heteroaryl, halo, hydroxyl, alkoxy, aryloxy, arylalkoxy, amino, akylamino, dialkylamino, thioyl, alkylthioyl, sulfonyl, sulfonamidyl, amido, urea, sulfonylurea, hydroxyl alkoxyl, alkoxy alkoxyl, acyl, nitro, cyano, each of which is optionally substituted with 1-3 R⁸; each R⁸ is independently Ci-C₆ alkyl, C₂-C₆ alkenyl, or C₂-C₆ alkynyl, halo, hydroxyl, alkoxy, aryloxy, amino, akylamino, dialkylamino, thioyl, sulfonyl, sulfonamidyl, amido, urea, sulfonylurea acyl, nitro, cyano, cyclyl, heterocyclyl, aryl, or heteroaryl; each m and n are independently 0, 1, 2, 3, 4, 5, or 6; and each R⁹ is independently H, Cj-C₆ alkyl, C₂-C₆ alkenyl, or C₂-C₆ alkynyl, halo, hydroxyl, alkoxy, aryloxy, arylalkoxy, amino, akylamino, dialkylamino, thioyl, alkylthioyl, sulfonyl, sulfonamidyl, amido, urea, sulfonylurea, acyl, nitro, cyano, each of which is optionally substituted with 1-3 R⁸. In another aspect, the invention features a compound of formula (V), or a pharmaceutically acceptable salt thereof:

Formula (V) wherein, R¹ and R² are each independently Cj-C₆ alkyl, C₂-C₆ alkenyl, or C₂-C₆ alkyny], each of which is optionally substituted with 1-4 R⁵;

L is is NR⁶SO₂, SO₂NR⁶, OC(O)NR⁶, NR⁶C(O)O, NR⁶C(O)NR⁶. NR⁶C(O), C(O)NR⁶, O, C(O),

S, S(O), S(O)₂, NR⁶, CH₂, cyclyl, aryl, heterocyclyl, or heteroaryl;

R³ is cyclyl, heterocyclyl, aryl, heteroaryl. each of which is optionally substituted with 1-4 R⁷; each R⁵ is independently halo, hydroxyl, alkoxy, amino, alkylamino, dialkylamino, cyano, nitro, amido, alkylamido, dialkylamido, thioyl, sulfonyl, cyclyl, heterocyclyl, aryl, or heteroaryl; each R⁶ is independently H, Cj-C₆ alkyl, arylalkyl, S(O)alkyl, acetyl, amidyl, or S(O)H; each R⁷ is independently Cj-C₆ alky], C₂-C₆ alkenyl, C₂-C₆ alkynyl, cyclyl, heterocyclyl, aryl, heteroaryl, halo, hydroxyl, alkoxy, aryloxy, arylalkoxy, amino, akylamino, dialkylamino, thioyl, alkylthioyl, sulfonyl, sulfonamidyl, amido, urea, sulfonylurea, hydroxyl alkoxyl, alkoxy alkoxyl, acyl, nitro, cyano, each of which is optionally substituted with 1-3 R⁸; each R is independently Q-C₆ alkyl, C₂-C₆ alkenyl, or C₂-C₆ alkynyl, halo, hydroxyl, alkoxy, aryloxy, amino, akylamino, dialkylamino, thioyl, sulfonyl, sulfonamidyl, amido, urea, sulfonylurea acyl, nitro, cyano, cyclyl, heterocyclyl, aryl, or heteroaryl;

R⁹ is H, Ci-C₆ alkyl, or arylalkyl; and each m and n are independently 0, 1, 2, 3, 4, 5, or 6.

In another aspect, the invention features a compound of formula (VI), or a pharmaceutically acceptable salt thereof:

R²

Formula (VI) wherein,

R^! is CpCe alky], C₂-C₆ alkenyl, C₂-C₆ alkynyl, each of which is optionally substituted with 1-4

R⁵;

R² is C]-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, or cycyl, each of which is optionally substituted with 1-4 R⁵; L is is NR⁶SO₂, SO₂NR⁶, OC(O)NR⁶, NR⁶C(O)O, NR⁶C(O)NR⁶, NR⁶C(O), C(O)NR⁶, O, C(O), S, S(O), S(O)₂, NR⁶, CH₂, cycly], aryl, heterocyclyl, or heteroaryl;

R³ is cycly], heterocyclyl, aryl, heteroaryl, each of which is optionally substituted with 1-4 R⁷; each R⁵ is independently halo, hydroxyl, alkoxy, amino, alkylamino, dialkylamino, cyano, nitro, amido, alkylamido, dialkylamido, thioyl, sulfonyl, cyclyl, heterocyclyl, aryl, or heteroaryl; each R⁶ is independently H, CpC₆ alky], arylalkyl, S(O)alkyl, acetyl, amidyl, or S(O)H; each R⁷ is independently C]-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, cyclyl, heterocyclyl, aryl, heteroaryl , halo, hydroxy], alkoxy, aryloxy, arylalkoxy, amino, akylamino, dialkylamino, thioyl , alkylthioyl, sulfonyl, sulfonamidyl, amido, urea, sulfonylurea, hydroxy] alkoxy], alkoxy alkoxy], acyl, nitro, cyano, each of which is optionally substituted with 1-3 R⁸; each R⁸ is independently C]-C₆ alky], C₂-C₆ alkenyl, or C₂-C₆ alkynyl, halo, hydroxy], alkoxy, aryloxy, amino, akylamino. dialkylamino, thioyl, sulfonyl, sulfonamidyl, amido, urea, sulfonylurea acyl, nitro, cyano, cycly], heterocyclyl, aryl, or heteroaryl; each R⁹ is independently H, CpC₆ alkyl, C₂-C₆ alkenyl, or C₂-C₆ alkynyl, halo, hydroxyl, alkoxy, aryloxy, arylalkoxy, amino, akylamino, dialkylamino, thioyl, alkylthioyl, sulfonyl, sulfonamidyl, amido, urea, sulfonylurea, acyl, nitro, cyano, each of which is optionally substituted with 1-3 R⁸; each m and n are independently 0, 1, 2, 3, 4, 5, or 6.

In another aspect, the invention features a compound of formula (VII), or a pharmaceutically acceptable salt thereof:

Formula (VII)

wherein,

R³ is cyclyl, heterocyclyl, aryl, heteroaryl, each of which is optionally substituted with 1-4 R ; each R⁵ is independently halo, hydroxyl, alkoxy, amino, alkylamino, dialkylamino, cyano, nitro, amido, alkylamido, dialkylamido, thioyl, sulfonyl, cycly], heterocyclyl, aryl, or heteroaryl; each R⁶ is independently H, C₁-C₆ alkyl, arylalkyl, S(O)alkyl, acetyl, amidyl, or S(O)H; each R⁷ is independently Q-C₆ alkyl, C₂-C₆ alkenyl, or C₂-C₆ alkynyl, halo, hydroxyl, alkoxy, aryl, heteroaryl, cyclyl, aryloxy, arylalkoxy, amino, akylamino, dialkylamino, thioyl, alkylthioyl, sulfonyl, sulfonamidyl, amido, hydroxyl alkoxyl, alkoxy alkoxyl, urea, sulfonylurea, acyl, nitro, cyano, each of which is optionally substituted with 1 -3 R ; each R⁸ is independently Ci-C₆ alkyl, C₂-C₆ alkenyl, or C₂-C₆ alkynyl, halo, hydroxyl, alkoxy, aryloxy, amino, akylamino, dialkylamino, thioyl, sulfonyl, sulfonamidyl, amido, urea, sulfonylurea acyl, nitro, cyano, cycly], heterocyclyl, aryl, or heteroaryl; and each m and n are independently O, 1 , 2, 3, 4, 5, or 6. In another aspect, the invention features a compound of formula (IX), or a pharmaceutically acceptable salt thereof:

Formula (IX) wherein,

R¹ and R² are each independently H, Ci-C₆ alky], C₂-CO alkenyl, or C₂-C6 alkynyl, each of which is optionally substituted with 1-4 R⁵;

L is NR⁶SO₂, SO₂NR⁶, OC(O)NR⁶, NR⁶C(O)O, NR⁶C(O)NR⁶, NR⁶C(O), C(O)NR⁶, O, S, S(O),

S(O)₂, NR⁶, or CH₂, R³ is cyclyl, heterocyclyl, aryl, heteroaryl, each of which is optionally substituted with 1 -4 R⁷; each R⁵ is independently halo, hydroxyl, alkoxy, amino, alkylamino, dialkylamino, cyano, nitro, amido, alkylamido, dialkylamido, thioyl, sulfonyl, cyclyl, heterocyclyl, aryl, or heteroaryl; each R⁶ is independently H, C₁-C₆ alkyl, arylalkyl, S(O)alkyl, acetyl, amidyl, or S(O)H; each R⁷ is independently Ci-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, cyclyl, heterocyclyl, aryl, heteroaryl, halo, hydroxyl, alkoxy, aryloxy, arylalkoxy, amino, akylamino, dialkylamino, thioyl, alkylthioyl, sulfonyl, sulfonamidyl, amido, urea, sulfonylurea, hydroxy] alkoxy], alkoxy alkoxyl, acyl, nitro, cyano, each of which is optionally substituted with 1-3 R⁸; each R⁸ is independently C]-C₆ alkyl, C₂-C₆ alkenyl, or C₂-C₆ alkynyl, halo, hydroxy], alkoxy, aryloxy, amino, akylamino, dialkylamino, thioyl, sulfonyl, sulfonamidyl, amido, urea, sulfonylurea acyl, nitro, cyano, cyclyl, heterocyclyl, aryl, or heteroaryl; each R⁹ is independently H, CpC₆ alkyl, C₂-C₆ alkenyl, or C₂-C₆ alkynyl, halo, hydroxyl, alkoxy, aryloxy, arylalkoxy, amino, akylamino, dialkylamino, thioyl, alkylthioyl, sulfonyl, sulfonamidyl, amido, urea, sulfonylurea, acyl, nitro, cyano, each of which is optionally substituted with 1-3 R⁸; m is 1, 2, 3, 4, 5, or 6; and n is O, 1 , 2, 3, 4, 5, or 6. In some embodiments, a compound described herein, for example, a compound of formula (II), (III), (IV), (V), (VI), (VII), (IX), can have one or more of the embodiments as described below.

In some embodiments, when X is CH₂, L is CH₂ and R³ is phenyl, R³ is not further substituted by 4-phenyl.

In some embodiments, X is CR₂, for example, CH.

In some embodiments, X is N.

In some embodiments, when L is heteroaryl or cyclopropyl, n is at least 1.

In some embodiments, R¹ is Cj-C₆ alky], for example, methyl. In some embodiments, R¹ is further substituted by a dialkyl amine, for example, a dimethyl amine.

I In some embodiments, wherein R¹ is '^- ^^ ^ .

In some embodiments, R¹ is C]-C_O alkyl substituted by heterocyclyl, for example a nitrogen containing heterocyclyl such as morpholinyl. In some embodiments, R³ is monocyclic, for example a monocyclic cyclyl, a monocyclic ary], a monocyclic heterocyclyl, or a monocyclic heteroaryl. In some embodiments, R³ is aryl, for example, phenyl.

In some embodiments, R³ is phenyl substituted by 1-3 R⁷. In some embodiments, R⁷ is Me, OMe, or halo. In some embodiments, at least 1 R⁷ is positioned in the para position. In some embodiments, R³ is phenyl substituted by 1 R⁷. In some embodiments, R⁷ is Me,

OMe, or halo. In some embodiments, R⁷ is positioned in the para position, for example, when R is Me, OMe, or halo, e.g., R⁷ is methyl.

In some embodiments, R is

In some embodiments, R³ is heterocyclyl, for example, a nitrogen containing heterocyclyl and/or a 5 membered heterocyclyl . In some embodiments, R³ is substituted by 1-3 R⁷. In some embodiments, at least 1 R⁷ is in the 3 position of the 5 membered ring. In some embodiments, R⁷ is Me, OMe, or halo. In some embodiments, R³ is substituted by 1 R⁷, for example, Me, OMe, or halo. In some embodiments, R⁷ is in the 3 position of the 5 membered ring, for example, when R⁷ is Me, OMe, or halo.

In some embodiments, R³ is a 6 membered heterocyclyl, for example, R is

In some embodiments, R >3 i •s heteroaryl, for example, a 5 or 6 membered heteroaryl, e.g., a 5 membered heteroaryl. In some embodiments, R³ is substituted by 1-3 R⁷, for example, Me, OMe, or halo. In some embodiments, at least 1 R⁷ is in the 3 position of the 5 membered ring, for example when R⁷ is Me, OMe, or halo. In some embodiments, R³ is substituted by 1 R⁷, for example, when R⁷ is Me, OMe, or halo. In some embodiments, R⁷ is in the 3 position of the 5 membered ring, for example, when R⁷ is Me, OMe, or halo. In some embodiments, R⁷ is in the 4 position of the 5 membered ring, for example, when R⁷ is Me, OMe, or halo.

In some embodiments, R³ is a nitrogen containing heteroaryl, for example,

. _{In some} em_bo_dimen_ts, _the 5 membered heteroaryl is substituted by R⁷ is in the 3 or 4 position of the 5 membered ring. In some embodiments, R³ is further substituted by a cyclyl, heterocyclyl, aryl, heteroaryl (e.g., phenyl, or thiophenyl, each of which is independently optionally substituted with 1-4 R⁷). In

some embodiments, R³ is R⁷.

In some embodiments, R³ is a 6 membered heteroaryl, for example, substituted by 1-3 R⁷ such as Me, OMe, or halo. In some embodiments, at least 1 R⁷ is positioned in the para position, for example, when R⁷ is Me, OMe, or halo. In some embodiments, R³ is substituted by 1 R⁷, for example, when R⁷ is Me, OMe, or halo. In some embodiments, R⁷ is positioned in the para position, for example, when R⁷ is Me, OMe, or halo.

In some embodiments, R³ is

In some embodiments, R³ is a heteroaryl or heterocycyl having two fused rings. In some embodiments, R³ is a heteroaryl or heterocycyl having three fused rings.

In some embodiments, L is L is NR⁶SO₂, SO₂NR⁶, OC(O)NR⁶, NR⁶C(O)O, NR⁶C(O)NR⁶, S, S(O), S(O)₂, C(O)NS(O)₂, S(O)₂NC(O), heteroaryl, or cyclyl. In some embodiments, L is NR⁶SO₂ or SO₂NR⁶, OC(O)NR⁶, NR⁶C(O)O, NR⁶C(O)NR⁶.

In some embodiments, R⁶ is H.

In some embodiments, L is OC(O)NR⁶ or NR⁶C(O)O. In some embodiments, R⁶ is H.

In some embodiments, L is NR⁶C(O)NR⁶. In some embodiments, R⁶ is H.

In some embodiments, L is cyclyl or heterocyclyl, for example, cyclopropyl. In some embodiments, L is C(O)NR⁶ or NR⁶C(O). In some embodiments, R⁶ is H.

In some embodiments, R⁹ is H.

In some embodiments, R⁹ is halo, for example, chloro.

In some embodiments, m is 1.

In some embodiments, n is 2. In some embodiments, m is 1 and n is 2, for example, where L is C(O)NR⁶.

In some embodiments, n is O.

In some embodiments, m is 1 and n is O, for example, where R³ is aryl or heteroaryl (e.g., further substituted by at least one R⁷).

In some embodiments, m+n < 6. One aspect of the present invention provides a pharmaceutical preparation suitable for use in a human patient, or for veterinary use. comprising an effective amount of any of the compounds shown above (e.g., a compound described herein or a salt thereof, or a solvate, hydrate, oxidative metabolite or prodrug of the compound or its salt), and one or more pharmaceutically acceptable excipients. In certain embodiments, the pharmaceutical preparations may be for use in treating or preventing a condition involving activation of TRPAl or for which reduced TRPAl activity can reduce the severity. In certain embodiments, the pharmaceutical preparations have a low enough pyrogen activity to be suitable for use in a human patient, or for veterinary use. In certain embodiments, the pharmaceutical preparation comprises an effective amount of any of the compounds shown above, wherein the compound inhibits TRPAl (e.g., a TRPAl -mediated current and/or TRPAl -mediated ion flux) with an IC₅₀ of 10 micromolar or less. In certain embodiments, the pharmaceutical preparation comprises a compound which inhibits TRPAl with an IC₅₀ of 5 micromolar or less, 2 micromolar or less, 1 micrornolar or less, or even with an IC₅₀ of 500 nM or less, 250 nM or less, 200 nM or less, or even 100 nM or less.

In another aspect, the invention contemplates that any of the TRPAl inhibitors of the present invention, including inhibitors having one or more of the characteristics disclosed herein, can be used to inhibit a function of TRPAl, for example a TRPAl -mediated current and/or a TRPAl -mediated ion flux. In some embodiments, the compounds can be used to inhibit a TRPAl mediated current in vitro, for example in cells in culture. In some embodiments, the compounds can be used to inhibit a TRPAl mediated current in vivo. In certain embodiments, the compounds inhibit both an inward and an outward TRPAl -mediated current. In certain embodiments, the compounds inhibit a TRPAl mediated ion flux in vitro, for example in cells in culture. In certain other embodiments, the compounds inhibit a TRPAl mediated in flux in vivo. The invention contemplates pharmaceutical preparations and uses of TRPAl antagonists having any combination of the foregoing or following characteristics, as well as any combination of the structural or functional characteristics of the TRPAl antagonists described herein. Any such antagonists or preparations can be used in the treatment of any of the diseases or conditions described herein. Any such antagonists or preparations can be used to inhibit a function of TRPAl, for example a TRPAl -mediated current and/or a TRPAl -mediated ion flux.

Detailed Description of the Invention

Cellular homeostasis is a result of the summation of regulatory systems involved in, amongst other things, the regulation of ion flux and membrane potential. Cellular homeostasis is achieved, at least in part, by movement of ions into and out of cells across the plasma membrane and within cells by movement of ions across membranes of intracellular organelles including, for example, the endoplasmic reticulum, sarcoplasmic reticulum, mitochondria and endocytic organelles including endosomes and lysosomes.

Movement of ions across cellular membranes is carried out by specialized proteins. TRP channels are one large family of non-selective cation channels that function to help regulate ion flux and membrane potential. TRP channels are subdivided into 6 sub-families including the TRPA (ANKTM 1 ) family. TRPA l is a member of the TRPA class of TRP channels. Non-selective cation channels such as TRPAl modulate the flux of calcium and sodium ions across cellular membranes. Sodium and calcium influx leads to a depolarization of the cell. This increases the probability that voltage-gated ion channels will reach the threshold required for activation. As a result, activation of non-selective cation channels can increase electrical excitability and increase the frequency of voltage-dependent events. Voltage-dependent events include, but are not limited to, neuronal action potentials, cardiac action potentials, smooth muscle contraction, cardiac muscle contraction, and skeletal muscle contraction.

Calcium influx caused by the activation of non-selective cation channels such as TRPAl also alters the intracellular free calcium concentration. Calcium is a ubiquitous second messenger molecule within the cell. Thus alterations in intracellular calcium levels have profound effects on signal transduction and gene expression. Thus, activation of non-selective cation channels such as TRPAl can lead to changes in gene expression and cellular phenotype. Gene expression events include, but are not limited to, production of mRNAs encoding cell surface receptors, ion channels, and kinases. These changes in gene expression can lead to hyperexcitability in that cell. Blockers of TRPAl therefore also have the potential to decrease or prevent pain and/or to decrease overactive bladder.

TRPAl proteins are receptor operated channels expressed in sensory neurons (see, e.g., Jordt et al. (2004) Nature 427:260-265) including those with cell bodies residing in the dorsal root ganglion, trigeminal ganglion, and nodose ganglia (see Jordt et al. (2004) Nature 427:260- 265, Nagata et al. (2005) J. Neurosci 25( 16) 4052-61 ). In addition, low levels of TRPAl message can be found in some types of fibroblasts (see Jaquemar et al. (1999) JBC 274(11): 7325-33). TRPAl has also been reported to be expressed in the bladder. Stimulation of a number of extracellular receptors, including, but not limited to, G-protein coupled receptors or receptor tyrosine kinases are sufficient to activate TRPAl . TRPAl is the ion channel that responds to mustard oil. The active ingredients in mustard oil (ally] isothiocyanate) and the active ingredient in garlic (allicin) are both capable of activating TRPAl . Other stimuli may also be able to activate TRPAl . It has been reported that severe cold temperatures between 4 and 15 ⁰C activate TRPAl (see Story et al., (2003) Cell 112(6): 819- 829). However, this finding has been controversial (see Jordt et al. (2004) Nature 427:260-265; Nagata et al. (2005) J. Neurosci 25(16): 4052-61). In addition, TRPAl shares many structural similarities with TRP channels (i.e., TRPNl, Drosophila TRPAl) in lower animals that respond to mechanical stimulation.

Modulating the function of TRPAl proteins provides a means of modulating calcium homeostasis, sodium homeostasis, membrane polarization, and/or intracellular calcium levels, and compounds that can modulate TRPAl function are useful in many aspects, including, but not limited to, maintaining calcium homeostasis, modulating intracellular calcium levels, modulating membrane polarization, and treating or preventing diseases, disorders, or conditions associated with calcium and/or sodium homeostasis or dyshomeostasis.

In certain aspects, the present invention provides methods for treating or ameliorating the effects of diseases and conditions using small molecules that inhibit a TRPAl -mediated current and/or a TRPAl -mediated ion flux with an IC₅₀ of less than 10 micromolar. Exemplary suitable compounds for use in any of the methods of the invention (e.g., to treat any of the diseases or conditions disclosed herein) include compounds having one or more of the structural or functional characteristics disclosed herein (e.g., structure, specificity, potency, solubility, etc.). The present invention contemplates the use of any TRPAl antagonist possessing one or more of the functional or structural attributes described herein. Additionally, the present invention contemplates the use of TRPAl antagonists of Formula VII, as well as the use of any of the particular antagonists described herein. Throughout the application, when particular functional attributes are attributed to TRPAl antagonists, it is understood that such attributes may characterize TRPAl inhibitors structurally related to or differing from compound of Formula VII.

In certain embodiments, a suitable compound inhibits an inward and/or outward TRPAl mediated current with an ICsoof less than 10 micromolar. In certain embodiments, a suitable compound additionally or alternatively inhibits TRPAl mediated ion flux with an ICsoof less than 10 micromolar. ICsocan be calculated, for example, in an in vitro assay. For example, IC50 can be calculated using electrophysiological determinations of current, such as standard patch clamp analysis. IC₅₀ can also be evaluated using changes in concentration or flux of ion indicators, such as the calcium flux methods described herein.

One aspect of the present invention provides a pharmaceutical preparation suitable for use in a human patient, or for veterinary use, comprising an effective amount of any of the compounds shown above (e.g., a compound described herein or a salt thereof, or a solvate, hydrate, oxidative metabolite or prodrug of the compound or its salt), and one or more pharmaceutically acceptable excipients. In certain embodiments, the pharmaceutical preparations may be for use in treating or preventing a condition involving activation of TRPAl or for which reduced TRPAl activity can reduce the severity. In certain embodiments, the pharmaceutical preparations have a low enough pyrogen activity to be suitable for use in a human patient, or for veterinary use. In certain embodiments, the pharmaceutical preparation comprises an effective amount of any of the compounds shown above, wherein the compound inhibits TRPAl with an IC₅₀ of 10 micromolar or less. In certain embodiments, the pharmaceutical preparation comprises a compound which inhibits TRPAl with an IC50 of 1 micromolar or less, or even with an IC₅₀ of 500 nM or less, 250 nM or less, 200 nM or less, or even 100 nM or less.

In certain embodiments, the TRPAl inhibitor for use in methods or pharmaceutical preparations of the present invention is selected from a compound described herein. In certain embodiments, the present invention contemplates the use of any compound as depicted in optionally substituted in any of the methods or pharmaceutical preparations of the present invention.

In certain embodiments, the invention contemplates that any of the particular compounds described herein can be administered to treat any of the diseases or conditions disclosed herein. In some embodiments, the compound is formulated as a pharmaceutical preparation prior to administration. In certain embodiments, the TRPAl inhibitor for use in methods or pharmaceutical preparations of the present invention is selected from a compound described herein. In certain embodiments, the present invention contemplates the use of any compound as described herein in any of the methods or pharmaceutical preparations of the present invention. The particular compounds and structural formulas disclosed herein are merely exemplary. The use of small molecule TRPAl inhibitors having one or more of the functional or structural characteristics described herein are similarly contemplated,

Compounds of any of the above structures may be used in the manufacture of medicaments for the treatment of any diseases disclosed herein.

Compounds of any of the above structures may be used to inhibit a function of a TRPAl channel in vitro or in vivo. In certain embodiments, compounds that include all or a functional portion of any of the foregoing structures may be used in the manufacture of medicaments for the treatment of any of the diseases disclosed herein. Additionally or alternatively, such compounds may be used in in vitro or in vivo methods of inhibiting TRPAl function, such as a TRPAl -mediated current. In certain embodiments, a compound which is an antagonist of TRPAl is chosen to selectively antagonize TRPAl over other ion channels, e.g., the compound modulates the activity of TRPAl at least an order of magnitude more strongly than it modulates the activity of one or more of NaV 1.2, Cavl .2, Cav3.1, HERG, and/or mitochondrial uniporter, preferably at least two orders of magnitude more strongly, even more preferably at least three orders of magnitude more strongly. In certain embodiments, the compound modulates the activity of TRPAl at least 1.5 orders of magnitude more strongly than the activity of one or more of NaV 1.2, Cavl.2, Cav3.1, HERG, or mitochondrial uniporter. Such comparisons may be made, for example, by comparing IC₅₀ values.

In particular embodiments, the small molecule is chosen for use because it is more selective for one TRP isoform than others, e.g., 10-fold, and more preferably at least 100- or even 1000-fold more selective for TRPAl over one or more of TRPC6, TRPV5, TRPV6, TRPM8, TRPVl, HERG, NaV 1.2, mitochondrial uniporter, TRPV3 and/or TRPV4. In other embodiments, the differential is smaller, e.g., it more strongly inhibits TRPAl than TRPM8, TRPVl and/or TRPV4, preferably at least twice, three times, five times, or even ten times more strongly. Such comparisons may be made, for example, by comparing IC₅₀ values.

In certain embodiment, a small molecule is chosen because it antagonizes the function of both TRPAl and TRPM8. TRPVl and/or TRPV3. Although such compounds selectively antagonize the function of both ion channels, the IC₅₀ values need not be identical.

In certain embodiments of any of the foregoing, the small molecule may be chosen because it is capable of inhibiting receptor-mediated (or cold/stress mediated) activation of

TRPAl . In certain embodiments, the TRPAl antagonist inhibits receptor mediated activation of TRPAl and mustard oil induced activation of TRPAl . In certain other embodiments, the TRPAl antagonist inhibits receptor operated activation of TRPAl but does not inhibit mustard oil induced activation of TRPAl . In certain other embodiments, the TRPAl antagonist inhibits mustard oil induced activation of TRPAl but does not inhibit cold mediated activation of TRPAl. In certain embodiments of any of the foregoing, the small molecule may be chosen because it inhibits a TRPAl function with an IC₅₀ less than or equal to 1 uM, or even less than or equal to 700, 600, 500, 400, 300, 250, 200, or 100 nM. In other embodiments, the small molecule is chosen because it inhibits a TRPAl function with an ICs₀ less than or equal to 75 nM, less than or equal to 50 nM, or even less than or equal to 25, 10, 5, or 1 nM. In certain other embodiments of any of the foregoing, the small molecule inhibits TRPAl function with an IC50 less than or equal to 10 micromolar or less than or equal to 5 micromolar or less than or equal to 2.5 micromolar or less than or equal to 1.5 micromolar.

In certain embodiments of any of the foregoing, the compound may be chosen based on the rate of inhibition of a TRPAl function. In one embodiment, the compound inhibits a TRPAl function in less than 5 minutes, preferably less than 4, 3, or 2 minutes. In another embodiment, the compound inhibits a TRPAl function in less than about 1 minute. In yet another embodiment, the compound inhibits a TRPAl function in less than about 30 seconds.

In any of the foregoing embodiments, the small molecule antagonist of TRPAl function may inhibit the outward current, the inward current, or any combination of one or more of these currents. Compounds that inhibit more than one of the foregoing currents may do so with the same or with differing ICs₀ values. In any of the foregoing, the ability of a compound to inhibit a particular current can be assessed either in vitro or in vivo. Compounds that inhibit any of the foregoing currents in an in vitro or in vivo assay are characterized as compounds that inhibit a function of TRPAl . Stated another way, an exemplary function of TRPAl that may be inhibited by the present compounds is a TRPAl -mediated current. Additionally or alternatively, a further exemplary function of TRPAl that may be inhibited by the present compounds is ion flux mediated by TRPAl .

In certain embodiments of any of the foregoing, inhibition of a TRPAl function means that a function, for example a TRPAl mediated current, is decreased by greater than 50% in the presence of an effective amount of a compound in comparison to in the absence of the compound or in comparison to an ineffective amount of a compound. In certain other embodiments, the inhibition of a TRPAl function means that a function, for example a TRPAl mediated current or TRPAl mediated ion flux, is decreased by at least 50%, 60%, 70%, 75%, 80%, 85%, or 90% in the presence of an effective amount of a compound in comparison to in the absence of the compound. In still other embodiments, the inhibition of a TRPAl function means that a function, for example a TRPAl mediated current, is decreased by at least 92%, 95%, 97%, 98%, 99%, or 100% in the presence of an effective amount of a compound in comparison to in the absence of the compound.

In any of the foregoing embodiments, IC₅₀ values are measured in vitro using, for example, patch clamp analysis or standard measurements of calcium flux. Exemplary in vitro methods for calcium flux-based IC₅₀ estimation are described in Example 1. Methods used to obtain more definitive IC₅₀ measurements are described in Example 2. Alternatively, estimates of % inhibition of current or ion flux can also be calculated and used to assess efficacy of a compound as an inhibitor. In certain embodiments of any of the foregoing, the TRPAl inhibitor is used to treat or ameliorate pain. Exemplary classes of pain that can treated using a TRPAl inhibitor include, but are not limited to nociceptive pain, inflammatory pain, and neuropathic pain. Pain that can be treated with a TRPAl inhibitor can be chronic or acute. Throughout the specification, a variety of conditions and diseases characterized, at least in part, by pain are discussed in detail. The invention contemplates that the pain associated with any of these diseases or conditions can be treated using any of the TRPAl inhibitors described herein. The inhibitor can be formulated in a pharmaceutical preparation appropriate for the intended route of administration. The invention contemplates pharmaceutical compositions of any of the foregoing TRPAl inhibitors. Exemplary pharmaceutical compositions are formulated in a pharmaceutically acceptable carrier. The subject TRPAl inhibitors can be used alone or as part of a therapeutic regimen combined with other treatments, therapies, or interventions appropriate for the particular disease, condition, injury or disorder being treated. When used as part of a therapeutic regimen, the invention contemplates use of TRPAl inhibitors in combination with one or more of the following treatment modalities: administration of non-TRPAl inhibitor pharmaceuticals, chemotherapy, radiotherapy, homeopathic therapy, diet, stress management, and surgery.

When administered alone or as part of a therapeutic regimen, in certain embodiments, the invention contemplates administration of TRPAl inhibitors to treat a particular primary disease, injury, disorder, or condition. Additionally or alternatively, the invention contemplates administration of TRPAl inhibitors to treat pain associated with a disease, injury, disorder, or condition. In still other embodiments, the invention contemplates administration of TRPAl inhibitors to treat symptoms secondary to the primary disease, injury, disorder, or conditions. The invention contemplates pharmaceutical preparations and uses of TRPAl antagonists having any combination of the foregoing or following characteristics, as well as any combination of the structural or functional characteristics of the TRPAl antagonists described herein. Any such antagonists or preparations can be used in the treatment of any of the diseases or conditions described herein. Additionally, the invention contemplates the use of any such antagonists or preparations for inhibiting a TRPAl mediated current in vitro. Combinations of any of the foregoing or following aspects and embodiments of the invention are also contemplated. For example, the invention contemplates that TRPAl antagonists having any of the particular potencies and specificities outlined herein can be formulated for the appropriate route of administration and can be used in treating any of the conditions or diseases detailed herein.

Definitions

The term "acyl" is art-recognized and refers to a group represented by the general formula hydrocarbylC(O)-, preferably alkylC(O)-. The term "acylamino" is art-recognized and refers to a moiety that can be represented by the general formula: O

— N-

wherein R⁹ is as defined above, and R'¹¹ represents a hydrogen, an alkyl, an alkenyl or

-(CKb)In-R , where m and R are as defined above. The term "aliphatic group" refers to a straight-chain, branched-chain, or cyclic aliphatic hydrocarbon group and includes saturated and unsaturated aliphatic groups, such as an alkyl group, an alkenyl group, and an alkynyl group.

The term "alkenyl", as used herein, refers to an aliphatic group containing at least one double bond. The terms "alkoxyl" or "alkoxy" as used herein refers to an alkyl group, as defined below, having an oxygen radical attached thereto. Representative alkoxyl groups include methoxy, ethoxy, propyloxy, tert-butoxy and the like. An "ether" is two hydrocarbons covalently linked by an oxygen.

The term "alkyl" refers to the radical of saturated aliphatic groups, including straight- chain alkyl groups, branched-chain alkyl groups, cycloalkyl (alicyclic) groups, alkyl-substituted cycloalkyl groups, and cycloalkyl-substituted alkyl groups. In preferred embodiments, a straight chain or branched chain alkyl has 30 or fewer carbon atoms in its backbone (e.g., C₁-C30 for straight chains, C₃-C3₀ for branched chains), and more preferably 20 or fewer, and most preferably 10 or fewer. Likewise, preferred cycloalkyls have from 3-10 carbon atoms in their ring structure, and more preferably have 5, 6 or 7 carbons in the ring structure.

The term "alkynyl", as used herein, refers to an aliphatic group containing at least one triple bond.

The term "alkylthio" refers to an hydrocarbyl having a sulfur radical attached thereto. In preferred embodiments, the "alkylthio" moiety is represented by one of -S-alkyl, -S-alkenyl, -S- alkynyl. Representative alkylthio groups include methyl thio, ethylthio, and the like.

The terms "amine" and "amino" are art-recognized and refer to both unsubstituted and substituted amines, e.g., a moiety that can be represented by the general formula:

wherein R⁹, Rⁱ⁰ and R'¹ each independently represent a hydrogen, an alkyl, an alkenyl, -(CH₂)_m-R⁸, or R⁹ and R¹⁰ taken together with the N atom to which they are attached complete a heterocycle having from 4 to 8 atoms in the ring structure; R⁸ represents an aryl, a cycloalkyl, a cycloalkenyl, a heterocycle or a polycycle; and m is zero or an integer in the range of 1 to 8.

The term "amido" refers to a moiety that can be represented by the general formula:

R¹⁰ wherein R⁹, R¹⁰ are as defined above.

The term "aralkyl", as used herein, refers to an alkyl group substituted with an aryl group (e.g., an aromatic or heteroaromatic group).

The term "aryl" as used herein includes 5-, 6-, and 7-membered single-ring aromatic groups that may include from zero to four heteroatoms, for example, benzene, pyrrole, furan, thiophene, imidazole, oxazole, thiazole, triazole, pyrazole, pyridine, pyrazine, pyridazine and pyrimidine, and the like. Those aryl groups having heteroatoms in the ring structure may also be referred to as "aryl heterocycles" or "heteroaromatics." The aromatic ring can be substituted at one or more ring positions with such substituents as described above, for example, halogen, azide, alky], aralkyl, alkenyl, alkynyl, cycloalkyl, polycyclyl, hydroxyl, alkoxyl, amino, nitro, sulfhydryl, imino, amido, phosphate, phosphonate, phosphinate, carbonyl, carboxyl, silyl, ether, alkylthio, sulfonyl, sulfonamido, ketone, aldehyde, ester, heterocyclyl, aromatic or heteroaromatic moieties, -CF3, -CN, or the like. The term "aryl" also includes polycyclic ring systems having two or more cyclic rings in which two or more carbons are common to two adjoining rings (the rings are "fused rings") wherein at least one of the rings is aromatic, e.g., the other cyclic rings can be cycloalkyls, cycloalkenyls, cycloalkynyls, aryls and/or heterocyclyls. The term "carbocycle or cycyl", as used herein, refers to an aromatic or non-aromatic ring in which each atom of the ring is carbon.

The term "carbonyl" refers to moieties represented by the general formula:

O O

^X'^R11 °^Γ ^X^R¹¹¹ wherein X is a bond or represents an oxygen or a sulfur, and R¹ ' represents a hydrogen, an alkyl, an alkenyl, -(CH2)_m-R or a pharmaceutically acceptable salt, R¹ represents a hydrogen, an alkyl, an alkenyl or -(CH2)_m-R⁸, where m and R⁸ are as defined above. Where X is an oxygen and Rⁿ or R'" is not hydrogen, the formula represents an "ester". Where X is an oxygen, and R¹¹ is as defined above, the moiety is referred to herein as a carboxyl group, and particularly when R^{! 1} is a hydrogen, the formula represents a "carboxylic acid". Where X is an oxygen, and R'^{1 1} is hydrogen, the formula represents a "formate". In general, where the oxygen atom of the above formula is replaced by sulfur, the formula represents a "thiocarbonyl" group. Where X is a sulfur and R¹ ' or R'¹ ' is not hydrogen, the formula represents a "thioester." Where X is a sulfur and R¹¹ is hydrogen, the formula represents a "thiocarboxylic acid." Where X is a sulfur and R¹¹' is hydrogen, the formula represents a "thiolformate." On the other hand, where X is a bond, and R¹ ' is not hydrogen, the above formula represents a "ketone" group. Where X is a bond, and R" is hydrogen, the above formula represents an "aldehyde" group.

The term "ester", as used herein, refers to a group -C(O)OR⁹ wherein R⁹ represents a hydrocarbyl group.

The terms "halo" and "halogen" as used herein means halogen and includes chloro, fluoro, bromo, and iodo. The terms "hetaralkyl" and "heteroaralkyl", as used herein, refers to an alkyl group substituted with a hetaryl group.

The terms "heterocyclyl" or "heterocyclic group" refer to 3- to 10-membered ring structures, more preferably 3- to 7-membered rings, whose ring structures include one to four heteroatoms. Heterocycles can also be polycycles, with each group having, e.g., 5-7 ring members. The term "heterocyclyl" or "heterocyclic group" includes "heteroaryl" and "saturated or partially saturated heterocyclyl" structures. The term "heteroaryl" refers to an aromatic 5-8 membered monocyclic, 8-12 membered bicyclic, or 11-14 membered tricyclic ring system having 1-3 heteroatoms if monocyclic, 1-6 heteroatoms if bicyclic, or 1-9 heteroatoms if tricyclic, said heteroatoms selected from O, N, or S (e.g., carbon atoms and 1-3, 1-6, or 1-9 heteroatoms of N, O, or S if monocyclic, bicyclic, or tricyclic, respectively). Any ring atom can be substituted (e.g., by one or more substituents). The term "saturated or partially saturated heterocyclyl" refers to a non-aromatic cylic structure that includes at least one heteroatom. Heterocyclyl groups include, for example, thiophene, thianthrene, furan, pyran, isobenzofuran, chromene, xanthene, phenoxathiin, pyrrole, imidazole, pyrazole, isothiazole, isoxazole, pyridine, pyrazine, pyrimidine, pyridazine, indolizine, isoindole, indole, indazole, purine, quinolizine, isoquinoline, quinoline, phthalazine, naphthyridine, quinoxaline, quinazoline, cinnoline, pteridine, carbazole, carboline, phenanthridine, acridine, pyrimidine, phenanthroline, phenazine, phenarsazine, phenothiazine, furazan, phenoxazine, pyrrolidine, oxolane, thiolane, oxazole, piperidine, piperazine, morpholine, lactones, lactams such as azetidinones and pyrrolidinones, sultams, sultones, and the like. The heterocyclic ring can be substituted at one or more positions with such substituents as described above, as for example, halogen, alkyl, aralkyl, alkenyl, alkynyl, cycloalkyl, hydroxyl, amino, nitro, sulfhydryl, imino, amido, phosphate, phosphonate, phosphinate, carbonyl, carboxyl, silyl, ether, alkylthio, sulfonyl, ketone, aldehyde, ester, a heterocyclyl, an aromatic or heteroaromatic moiety, -CF3, -CN, or the like.

The term "heterocyclylalkyl", as used herein, refers to an alkyl group substituted with a heterocycle group.

The term "hydrocarbyl", as used herein, refers to a group that is bonded through a carbon atom that does not have a =O or =S substituent, and typically has at least one carbon-hydrogen bond and a primarily carbon backbone, but may optionally include heteroatoms. Thus, groups like methyl, ethoxyethyl, 2-pyridyl, and trifluoromethyl are considered to be hydrocarbyl for the purposes of this application, but substituents such as acetyl (which has a =O substituent on the linking carbon) and ethoxy (which is linked through oxygen, not carbon) are not. Hydrocarbyl groups include, but are not limited to aryl, heteroaryl, carbocycle, heterocycle, alkyl, alkenyl, alkynyl, and combinations thereof. As used herein, the term "nitro" means -NO₂; the term "halogen" or "halo" designates -F,

-Cl, -Br or -I; the term "sulfhydryl" means -SH; the term "hydroxyl" means -OH; and the term "sulfonyl" means -SO₂-.

The terms "polycyclyl" or "polycyclic group" refer to two or more rings (e.g., cycloalkyls, cycloalkenyls, cycloalkynyls, aryls and/or heterocyclyls) in which two or more carbons are common to two adjoining rings, e.g., the rings are "fused rings". Rings that are joined through non-adjacent atoms are termed "bridged" rings. Each of the rings of the polycycle can be substituted with such substituents as described above, as for example, halogen, alkyl, aralkyl, alkenyl, alkynyl, cycloalkyl, hydroxyl, amino, nitro, sulfhydryl, imino, amido, phosphate, phosphonate, phosphinate, carbonyl, carboxyl, silyl, ether, alkylthio, sulfonyl, ketone, aldehyde, ester, a heterocyclyl, an aromatic or heteroaromatic moiety, -CF₃, -CN, or the like. Exemplary monocyclic rings include furan, thiophene, pyrrole, pyrroline, pyrrolodine, oxazole, thiazole, imidazole, imidazoline, pyrazole, pyrazoline, pyrazolidine, isoxazole, isothiazole, oxadiazole, triazole, thiadiazole, pyran, pyridine, piperidine, dioxane, morpholine, dithiane, thiomorpholine, pyridazine, pyrimidine, pyrazine, piperazine, triazine, and trithiane. Exemplary bicyclic rings include indolizinyl, indolyl, isoindolyl, indoliny], benzofurany], benzothiophenyl, indazolyl, benzimidazolyl, benthiazolyl, purinyl, quinolizinyl, quinolinyl, isoquinolinyl, cinnolinyl, phthalazinyl, quinazolinyl, quinoxalinyl, naphthyridinyl, pteridinyl, indenyl, naphthalenyl, azulenyl, imidazopyridazionyl, pyrazolopyrimidinediony], or pyrrolopyrimidinediony] moieties. Exemplary tricyclic rings include carbazole, acridine, phenazine, phenothiazine, phenoxazine, fluorine, and anthracene.

The phrase "protecting group" as used herein means temporary substituents which protect a potentially reactive functional group from undesired chemical transformations. Examples of such protecting groups include esters of carboxylic acids, silyl ethers of alcohols, and acetals and ketals of aldehydes and ketones, respectively. The field of protecting group chemistry has been reviewed (Greene, T. W.; Wuts, P.G.M. Protective Groups in Organic Synthesis, 2^nd ed.; Wiley: New York, 1991).

The term "substituted" refers to moieties having substituents replacing a hydrogen on one or more carbons of the backbone. It will be understood that "substitution" or "substituted with" includes the implicit proviso that such substitution is in accordance with permitted valence of the substituted atom and the substituent, and that the substitution results in a stable compound, e.g., which does not spontaneously undergo transformation such as by rearrangement, cyclization, elimination, etc. As used herein, the term "substituted" is contemplated to include all permissible substituents of organic compounds. In a broad aspect, the permissible substituents include acyclic and cyclic, branched and unbranched, carbocyclic and heterocyclic, aromatic and non-aromatic substituents of organic compounds. The permissible substituents can be one or more and the same or different for appropriate organic compounds. For purposes of this invention, the heteroatoms such as nitrogen may have hydrogen substituents and/or any permissible substituents of organic compounds described herein which satisfy the valences of the heteroatoms. Substituents can include any substituents described herein, for example, a halogen, a hydroxyl, a carbonyl (such as a carboxyl, an alkoxycarbonyl, a formyl, or an acyl), a thiocarbonyl (such as a thioester, a thioacetate, or a thioformate), an alkoxyl, a phosphoryl, a phosphate, a phosphonate. a phosphinate, an amino, an amido, an amidine, an imine, a cyano, a nitro, an azido, a sulfhydryl, an alkylthio, a sulfate, a sulfonate, a sulfamoyl, a sulfonamido, a sulfonyl, a heterocyclyl, an aralkyl, or an aromatic or heteroaromatic moiety. It will be understood by those skilled in the art that the moieties substituted on the hydrocarbon chain can themselves be substituted, if appropriate. For instance, the substituents of a substituted alkyl may include substituted and unsubstituted forms of amino, azido, imino, amido, phosphoryl (including phosphonate and phosphinate), sulfonyl (including sulfate, sulfonamido, sulfamoyl and sulfonate), and silyl groups, as well as ethers, alkylthios, carbonyls (including ketones, aldehydes, carboxylates, and esters), -CF₃, -CN and the like. Exemplary substituted alkyls are described below. Cyclαalkyls can be further substituted with alkyls, alkenyls, alkoxys, alkylthios, aminoalkyls, carbonyl-substituted alkyls, -CF₃, -CN, and the like. Analogous substitutions can be made to alkenyl and alkynyl groups to produce, for example, aminoalkenyls, aminoalkynyls, amidoalkenyls, amidoalkynyls, iminoalkenyls, iminoalkynyls, thioalkenyls, thioalkynyls, carbonyl-substituted alkenyls or alkynyls. The term "sulfate" refers to a moiety that can be represented by the general formula:

O

-O-S-OR⁴¹ O in which R⁴¹ is as defined above.

The term "sulfonamido" refers to a moiety that can be represented by the general formula:

in which R⁹ and R'¹¹ are as defined above.

The term "sulfonate" refers to a moiety that can be represented by the general formula:

O

-S-OR⁴¹ O in which R⁴¹ is an electron pair, hydrogen, alkyl, cycloalkyl, or aryl.

The terms "sulfoxido" or "sulfinyl", as used herein, refers to a moiety that can be represented by the general formula -S(=O)-R⁴⁴, in which R⁴⁴ is selected from the group consisting of hydrogen, alkyl, alkenyl, alkynyl, cycloalkyl, heterocyclyl, aralkyl, or aryl.

The term "thioester", as used herein, refers to a group -C(O)SR⁹ Or-SC(O)R⁹ wherein R⁹ represents a hydrocarbyl.

As used herein, the definition of each expression, e.g., alkyl, m, n, etc., when it occurs more than once in any structure, is intended to be independent of its definition elsewhere in the same structure.

Certain compounds disclosed herein may exist in particular geometric or stereoisomeric forms. The present invention contemplates all such compounds, including cis- and trans-isomers, R- and 5-enantiomers, diastereomers, (d)-isomers, (l)-isomers, the racemic mixtures thereof, and other mixtures thereof, as falling within the scope of the invention. For example, if one chiral center is present in a molecule, the invention includes racemic mixtures, enantiomerically enriched mixtures, and substantially enantiomerically pure compounds. The composition can contain, e.g., more than 50%, more than 60%, more than 70%, more than 80%, more than 90%, more than 95%, or more than 99% of a single enantiomer. The "enantiomeric excess" or "% enantiomeric excess" of a composition can be calculated using the equation shown below. In the example shown below a composition contains 90% of one enantiomer, e.g., the S enantiomer, and 10% of the other enantiomer, i.e., the R enantiomer. ee = (90-10)/-00 = 80%.

Thus, a composition containing 90% of one enantiomer and 10% of the other enantiomer is said to have an enantiomeric excess of 80%.

Methods of preparing substantially isomerically pure compounds are known in the art. If, for instance, a particular enantiomer of a compound disclosed herein is desired, it may be prepared by asymmetric synthesis, or by derivation with a chiral auxiliary, where the resulting diastereomeric mixture is separated and the auxiliary group cleaved to provide the pure desired enantiomers. Alternatively, where the molecule contains a basic functional group, such as amino, or an acidic functional group, such as carboxyl, diastereomeric salts may be formed with an appropriate optically active acid or base, followed by resolution of the diastereomers thus formed by fractional crystallization or chromatographic means well known in the art, and subsequent recovery of the pure enantiomers. Alternatively, enantiomerically enriched mixtures and pure enantiomeric compounds can be prepared by using synthetic intermediates that are enantiomerically pure in combination with reactions that either leave the stereochemistry at a chiral center unchanged or result in its complete inversion. Techniques for inverting or leaving unchanged a particular stereocenter, and those for resolving mixtures of stereoisomers are well known in the art, and it is well within the ability of one of skill in the art to choose an appropriate method for a particular situation. See, generally, Furniss et al. (eds.), Vogel's Encyclopedia of Practical Organic Chemistry 5^lh Ed., Longman Scientific and Technical Ltd., Essex, 1991, pp. 809-816; and Heller, Ace. Chem. Res. 23: 128 (1990). Contemplated equivalents of the compounds described above include compounds which otherwise correspond thereto, and which have the same general properties thereof (e.g., the ability to inhibit TRPAl activity), wherein one or more simple variations of substituents are made which do not adversely affect the efficacy of the compound. In general, the compounds disclosed herein may be prepared by the methods illustrated in the general reaction schemes as, for example, described below, or by modifications thereof, using readily available starting materials, reagents and conventional synthesis procedures. In these reactions, it is also possible to make use of variants which are in themselves known, but are not mentioned here.

The compounds described herein may also contain unnatural proportions of atomic isotopes at one or more of the atoms that constitute such compounds. For example, the compounds may be radiolabeled with radioactive isotopes, such as for example tritium (³H), iodine-125 (¹²⁵I) or carbon-14 (¹⁴C). All isotopic variations of the compounds disclosed herein, whether radioactive or not, are intended to be encompassed within the scope of the present invention. For example, deuterated compounds and compounds incorporated ¹³C are intended to be encompassed within the scope of the invention. Certain compounds disclosed herein can exist in unsolvated forms as well as solvated forms, including hydrated forms. In general, the solvated forms are equivalent to unsolvated forms and are encompassed within the scope of the present invention. Certain compounds disclosed herein may exist in multiple crystalline or amorphous forms. In general, all physical forms are equivalent for the uses contemplated by the present invention and are intended to be within the scope of the present invention.

As set out above, certain embodiments of the present compounds may contain a basic functional group, such as amino or alkylamino, and are, thus, capable of forming pharmaceutically acceptable salts with pharmaceutically acceptable acids. The term "pharmaceutically acceptable salts" in this respect, refers to the relatively non-toxic, inorganic and organic acid addition salts of compounds disclosed herein. These salts can be prepared in situ during the final isolation and purification of the compounds of the invention, or by separately reacting a purified compound of the invention in its free base form with a suitable organic or inorganic acid, and isolating the salt thus formed. Representative salts include the hydrobromide, hydrochloride, sulfate, bisulfate, phosphate, nitrate, acetate, valerate, oleate, palmitate, stearate, laurate, benzoate, lactate, phosphate, tosylate, citrate, maleate, fumarate, succinate, tartrate, napthylate, mesylate, glucoheptonate, lactobionate, and laurylsulphonate salts and the like. (See, for example, Berge et al. (1977) "Pharmaceutical Salts", J. Pharm. Sci. 66:1- 19.)

In other cases, the compounds disclosed herein may contain one or more acidic functional groups and, thus, are capable of forming pharmaceutically acceptable salts with pharmaceutically acceptable bases. The term "pharmaceutically acceptable salts" in these instances refers to the relatively non-toxic, inorganic and organic base addition salts of compounds disclosed herein. These salts can likewise be prepared in situ during the final isolation and purification of the compounds, or by separately reacting the purified compound in its free acid form with a suitable base, such as the hydroxide, carbonate or bicarbonate of a pharmaceutically acceptable metal cation, with ammonia, or with a pharmaceutically acceptable organic primary, secondary or tertiary amine. Representative alkali or alkaline earth salts include the lithium, sodium, potassium, calcium, magnesium, and aluminum salts and the like. Representative organic amines useful for the formation of base addition salts include ethylamine, diethylamine, ethylenediamine, ethanolamine, diethanolamine, piperazine and the like. (See, for example, Berge et al., supra)

The terms "antagonist" and "inhibitor" are used interchangeably to refer to an agent that decreases or suppresses a biological activity, such as to repress an activity of an ion channel, such as TRPAl . TRPAl inhibitors include inhibitors having any combination of the structural and/or functional properties disclosed herein. An "effective amount" of, e.g., a TRPAl antagonist, with respect to the subject methods of inhibition or treatment, refers to an amount of the antagonist in a preparation which, when applied as part of a desired dosage regimen brings about a desired clinical or functional result. Without being bound by theory, an effective amount of a TRPAl antagonist for use in the methods of the present invention, includes an amount of a TRPAl antagonist effective to decrease one or more in vitro or in vivo functions of a TRPAl channel. Exemplary functions include, but are not limited to, membrane polarization (e.g., an antagonist may promote hyperpolarization of a cell), ion flux, ion concentration in a cell, outward current, and inward current. Compounds that antagonize TRPAl function include compounds that antagonize an in vitro or in vivo functional activity of TRPAl . When a particular functional activity is only readily observable in an in vitro assay, the ability of a compound to inhibit TRPAl function in that in vitro assay serves as a reasonable proxy for the activity of that compound. In certain embodiments, an effective amount is an amount sufficient to inhibit a TRPAl -mediated current and/or the amount sufficient to inhibit TRPAl mediated ion flux.

The term "hydrate" as used herein, refers to a compound formed by the union of water with the parent compound. The term "oxidative metabolite" is intended to encompass compounds that are produced by metabolism of the parent compound under normal physiological conditions. Specifically, an oxidative metabolite is formed by oxidation of the parent compound during metabolism. For example, a thioether group may be oxidized to the corresponding sulfoxide or sulfone. The term "preventing," when used in relation to a condition, such as a local recurrence

(e.g., pain), a disease such as cancer, a syndrome complex such as heart failure or any other medical condition, is well understood in the art, and includes administration of a composition which reduces the frequency of, or delays the onset of, symptoms of a medical condition in a subject relative to a subject which does not receive the composition. Thus, prevention of cancer includes, for example, reducing the number of detectable cancerous growths in a population of patients receiving a prophylactic treatment relative to an untreated control population, and/or delaying the appearance of detectable cancerous growths in a treated population versus an untreated control population, e.g., by a statistically and/or clinically significant amount. Prevention of an infection includes, for example, reducing the number of diagnoses of the infection in a treated population versus an untreated control population, and/or delaying the onset of symptoms of the infection in a treated population versus an untreated control population. Prevention of pain includes, for example, reducing the magnitude of, or alternatively delaying, pain sensations experienced by subjects in a treated population versus an untreated control population. The term "prodrug" is intended to encompass compounds that, under physiological conditions, are converted into the therapeutically active agents of the present invention. A common method for making a prodrug is to include selected moieties that are hydrolyzed under physiological conditions to reveal the desired molecule. In other embodiments, the prodrug is converted by an enzymatic activity in the host animal. The term "solvate" as used herein, refers to a compound formed by solvation (e.g., a compound formed by the combination of solvent molecules with molecules or ions of the solute). The terms "TRPAl", "TRPAl protein", and "TRPAl channel" are used interchangeably throughout the application. These terms refer to an ion channel (e.g., a polypeptide) comprising the amino acid sequence set forth in SEQ DD NO: 1 , SEQ BD NO:3, or SEQ ID NO: 5 of WO 2007/073505, or an equivalent polypeptide, or a functional bioactive fragment thereof. In certain embodiments, the term refers to a polypeptide comprising, consisting of, or consisting essentially of, the amino acid sequence set forth in SEQ ID NO: 1, SEQ ID NO:3, or SEQ ID NO: 5. TRPAl includes polypeptides that retain a function of TRPAl and comprise (i) all or a portion of the amino acid sequence set forth in SEQ ID NO: 1, SEQ ID NO: 3 or SEQ ID NO: 5; (ii) the amino acid sequence set forth in SEQ ID NO: 1, SEQ ED NO:3 or SEQ ID NO: 5 with 1 to about 2, 3, 5, 7, 10, 15, 20, 30, 50, 75 or more conservative amino acid substitutions; (iii) an amino acid sequence that is at least 70%, 75%, 80%, 90%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 1, SEQ ID NO: 3 or SEQ ID NO: 5; and (iv) functional fragments thereof. Polypeptides of the invention also include homologs, e.g., orthologs and paralogs, of SEQ ID NO: 1 , SEQ ID NO: 3 or SEQ ID NO: 5. The term "treating" includes therapeutic treatments. The term "treatment refers" to administration to the host of one or more of the subject compositions. If it is administered prior to clinical manifestation of the unwanted condition (e.g., disease or other unwanted state of the host animal) then the treatment is prophylactic, (i.e., it protects the host against developing the unwanted condition), whereas if it is administered after manifestation of the unwanted condition, the treatment is therapeutic, (i.e., it is intended to diminish, ameliorate, or stabilize the existing unwanted condition or side effects thereof).

Exemplary compounds are provided in Tables 1-7 below:

Compounds of Formula (II) include those shown in Table 1. Table 1.

1 -

1 - (6H)-

Compounds of formula (III) are provided in Table 2 below.

Table 2.

1 H-

1 H- 1 H-

1 H-

1 H-

1 H- 1 H-

1 H-

1 -

1 H-

H-

Compounds of formula (IV) are provided in Table 3 below.

Table 3.

Compounds of formula (V) are provided in Table 4 below.

Table 4.

Compounds of formula (VI) are below in Table 5.

Table 5.

(4H)- (4H)-

-

Compounds of formula (VII) are produced in Table 6 below.

Table 6.

1 -

Compounds of formula IX are provided in Table 7 below.

Table 7. -

Indications

Cellular homeostasis is a result of the summation of regulatory systems involved in, amongst other things, the regulation of ion flux and membrane potential. Cellular homeostasis is achieved, at least in part, by movement of ions into and out of cells across the plasma membrane and within cells by movement of ions across membranes of intracellular organelles including, for example, the endoplasmic reticulum, sarcoplasmic reticulum, and mitochondria and endocytic organelles including endosomes and lysosomes. Movement of ions across cellular membranes is carried out by specialized proteins. TRP channels are one large family of non-selective cation channels that function to help regulate ion flux and membrane potential. TRP channels are subdivided into 6 sub-families including the TRPA (ANKTMl ) family, and TRPAl is a member of the TRPA class of TRP channels.

Non-selective cation channels such as TRPAl modulate the flux of calcium and sodium ions across cellular membranes. Sodium and calcium influx leads to depolarization of the cell. This increases the probability that voltage-gated ion channels will reach the threshold required for activation. As a result, activation of non-selective cation channels can increase electrical excitability and increase the frequency of voltage-dependent events. Voltage-dependent events include, but are not limited to, neuronal action potentials, cardiac action potentials, smooth muscle contraction, cardiac muscle contraction, and skeletal muscle contraction.

Calcium influx caused by the activation of non-selective cation channels such as TRPAl also alters the intracellular free calcium concentration. Calcium is a ubiquitous second messenger molecule within the cell, so alterations in intracellular calcium levels have profound effects on signal transduction and gene expression. As a result, activation of non-selective cation channels such as TRPAl can lead to changes in gene expression and cellular phenotype. Gene expression events include, but are not limited to, production of mRNAs encoding cell surface receptors, ion channels, and kinases. These changes in gene expression can lead to hyperexcitability in that cell.

TRPAl proteins are broad receptors for noxious chemicals, both endogenous and exogenous. They respond to any of a variety of stimuli that can induce cysteine modification (Hinman et al;., 2006; MacPherson et al. 2007). In addition TRPAl can function as a receptor operated channel. It expressed in sensory neurons (see, e.g., Jordt et al. (2004) Nature 427:260- 265) including those with cell bodies residing in the dorsal root ganglion, trigeminal ganglion, and nodose ganglia (see Jordt et al. (2004) Nature 427:260-265, Nagata et al. (2005) J. Neurosci 25(16) 4052-61). In addition, low levels of TRPAl message can be found in some types of fibroblasts (see Jaquemar et al. (1999) JBC 274(11): 7325-33). TRPAl has also been reported to be expressed in the bladder. Stimulation of a number of extracellular receptors, including, but not limited to, G-protein coupled receptors or receptor tyrosine kinases are sufficient to activate TRPAl.

Modulating the function of TRPAl proteins provides a means of modulating calcium homeostasis, sodium homeostasis, membrane polarization, and/or intracellular calcium levels, and compounds that can modulate TRPAl function are useful in many aspects, including, but not limited to, maintaining calcium homeostasis, modulating intracellular calcium levels, modulating membrane polarization, and treating or preventing diseases, disorders, or conditions associated with calcium and/or sodium homeostasis or dyshomeostasis. Thus, a compound described herein (e.g., TRPAl antagonist) can be used as part of a prophylaxis or treatment for a variety of disorders and conditions, described in more detail below. In other embodiments, the invention provides methods and compositions for inhibiting a function of a TRPAl channel in vitro or in vivo. The compounds described herein can be used in the treatment of any of the foregoing or following diseases or conditions, including in the treatment of pain associated with any of the foregoing or following diseases or conditions.

Treatment of Sensitivity to Pain and Touch, or Pain-Related Diseases or Disorders

In certain embodiments, the TRPAl inhibitor is used to treat or ameliorate pain. Exemplary classes of pain that can be treated using a TRPAl inhibitor include, but are not limited to nociceptive pain, inflammatory pain, and neuropathic pain. The pain can be chronic or acute. In certain embodiments, the TRPAl inhibitor is non-narcotic and has little or no narcotic side-effects. In certain other embodiments, the TRPAl inhibitor can be used to treat or ameliorate pain with fewer side-effects than narcotic pain relievers. Exemplary side-effects that may be substantially absent at effective dosages of TRPV3 inhibitors include one or more of exopthalmos, catalepsy, disruption of gut motility, and inhibition of sensation in non-injured areas of the body.

As outlined above, TRPAl inhibitors may be particularly useful in the treatment of pain associated with cancer, osteoarthritis, rheumatoid arthritis, post-herpetic neuralgia, burns, and other indications detailed above. To further illustrate, additional exemplary indications for which compounds disclosed herein can be used include oral pain, pelvic pain, Fabry's disease, complex regional pain syndrome, pancreatitis, and fibromyalgia syndrome. Fabry's disease

Vague complaints of pain in hands and feet may be a presenting feature. These symptoms are called acroparesthesias, as they reflect the peripheral neuropathy that is a frequent manifestation of the disease. This pain may be both episodic and chronic. Acute episodes may be triggered by exposure to extremes of temperature, stress, emotion, and/or fatigue.

The compounds disclosed herein may alo be used in connection with prevention or treatment of sensitivity to pain and touch. Pain or sensitivity to pain and touch may be indicated in a variety of diseases, disorders or conditions, including, but not limited to, diabetic neuropathy, breast pain, psoriasis, eczema, dermatitis, burn, post-herpetic neuralgia (shingles), nociceptive pain, peripheral neuropathic and central neuropathic pain, chronic pain, cancer and tumor pain, spinal cord injury, crush injury and trauma induced pain, migraine, cerebrovascular and vascular pain, sickle cell disease pain, rheumatoid arthritis pain, musculoskeletal pain including treating signs and symptoms of osteoarthritis and rheumatoid arthritis, orofacial and facial pain, including dental, temperomandibular disorder, and cancer related, lower back or pelvic pain, surgical incision related pain, inflammatory and non-inflammatory pain, visceral pain, psychogenic pain and soft tissue inflammatory pain, fibromyalgia-related pain, and reflex sympathetic dystrophy, and pain resulting from kidney stones or urinary tract infection.

Oral pain is a particular category of pain that may be treated using the TRPAl inhibitors disclosed herein. The term "oral pain" refers to any pain in the mouth, throat, lips, gums, teeth, tongue, or jaw. The term is used regardless of the cause of the pain and regardless of whether the oral pain is a primary or secondary symptom of a particular disease, injury, or condition. Oral pain has a large number of possible causes. In certain embodiments, oral pain is caused by an injury or disease of the mouth, jaw, teeth, gums, throat, lips, or tongue. In certain other embodiments, oral pain is a consequence of an injury or disease that primarily affects another part of the body. In still other embodiments, oral pain is a side effect of a therapy used to treat an injury or disease of the mouth or another part of the body. TRPAl inhibitors are useful in treating oral pain regardless of its cause.

In certain embodiments, oral pain is caused by ulcers, sores, or other lesions in the mouth. For example, oral pain may be caused by ulcers, sores, or other lesions on the tongue, gums, lips, throat, or other tissues of the mouth. Alternatively or additionally, oral pain may be caused by inflammation of the throat, tongue, gums, lips, or other tissues of the mouth. Inflammation may accompany ulcers or other lesions, or inflammation may occur prior to or in the absence of formation of ulcers or other lesions. The foregoing are merely exemplary of diseases and conditions that cause or lead to inflammation, lesions, ulcers, or other sources of oral pain. In other embodiments, the oral pain is due to an injury to the mouth, jaw, lips, gums, or teeth. In other embodiments, the oral pain is due to oral surgery, for example, surgery for cancer, tooth extraction, or jaw remodeling. Other conditions that may lead to oral ulcers, and thus oral pain, include, but are not limited to chickpox, herpes zoster, infectious mononucleosis, syphilis, tuberculosis, acute necrotizing gingivitis, and burning mouth syndrome.

Fibromyalgia (FMS; fibromyalgia syndrome) is a widespread musculoskeletal pain and fatigue disorder. Fibromyalgia is characterized by pain in the muscles, ligaments, and tendons. The condition affects more women than men, and occurs in people of all ages. Overall, FMS is estimated to afflict 3-6% of the population. Patients have described the pain associated with fibromylagia as deep muscular aching, throbbing, shooting, and stabbing. The pain sometimes includes an intense burning sensation. The pain and stiffness are often worse in the morning or after repetitive use of a particular muscle group.

Additionally, varying levels of fatigue ranging from mild to incapacitating are often associated with fibromylagia. Other symptoms of fibromylagia include gastrointestinal symptoms. Irritable bowel syndrome and IBS-like symptoms such as constipation, diarrhea, frequent abdominal pain, abdominal gas, and nausea occur in roughly 40 to 70% of FMS patients. Acid reflux or gastroesophogeal reflux disease (GERD) occurs at a similar frequency.

Another frequent and debilitating symptom of FMS is chronic headaches, including migraine and tension-type headaches. Such headaches are experienced by approximately 70% of FMS patients. Additionally, FMS patients often experience temporomandibular joint dysfunction syndrome (also known as TMJ) which produces pain in the jaw, teeth, and mouth. TMJ may also exacerbate headaches. Other common symptoms of FMS include, but are not limited to, premenstrual syndrome and painful periods; chest pain; morning stiffness; cognitive or memory impairment; numbness and tingling sensations; muscle twitching; irritable bladder; the feeling of swollen extremities; skin sensitivities; dry eyes and mouth; dizziness; and impaired coordination. Additionally, patients are often sensitive to odors, loud noises, and bright lights.

The impact of FMS on the patient is directly correlated with the level of pain and fatigue. Pain may be so severe as to interfere with normal work or family functioning. There is currently no cure for FMS, and current therapies focus primarily on improving sleep (to decrease fatigue) and treating pain. Compounds disclosed herein could be used to help manage the pain associated with FMS. Such pain includes, but is not limited to, oral pain in the jaw, teeth, and mouth. Such pain also includes non-oral musco-skeletal pain, pain due to headaches, and pain due to gastrointestinal symptoms.

Complex Regional Pain Syndrome (CRPS; also known as chronic regional pain syndrome) is a chronic pain condition. CRPS was formerly known as reflex sympathetic dystrophy (RSD). CRPS is a chronic, painful, and progressive neurological condition that affects skin, muscles, joints, and bones. The syndrome usually develops in an injured limb, such as a broken leg or following surgery. However, many cases involve only a minor injury, such as a sprain, and somtimes no precipitating injurious event can be identified. CRPS involves continuous, intense pain that is disproportionate to the severity of the injury. The pain worsens, rather than improves, over time.

Although CRPS can affect a variety of regions of the body, it most often affects the arms, legs, hands, or feet. Often the pain begins in one portion of a limb, but spreads over time to include the entire limb or even to include a different limb. Typical features include dramatic changes in the color and temperature of the skin over the affected limb or body part, accompanied by intense burning pain, skin sensitivity, sweating, and swelling. Generally, CRPS is characterized into two categories. Type I occurs in the absence of a precipitating nerve injury - although there may have been some other type of precipitating injury. Type II (formerly called causalgia) occurs following a nerve injury. These categories are merely descriptive, and do not correlate with symptomology or prognosis. Precipitating events associated with the onset of CRPS include the following: cerebral lesions, heart disease, heart attack, infection, paralysis on one side of the body (hemiplegia), radiation therapy, repetitive motion disorder (e.g., carpal tunnel syndrome), spinal cord disorders, surgery, and trauma (e.g., bone fracture, gunshot, car accident). However, in 10-20% of cases, no precipitating event can be found. Note that the injury that precedes the onset of CRPS may or may not be significant.

The symptoms of CRPS may progress in three stages. An acute stage occurs during the first 1-3 months and may include burning pain, swelling, increased sensitivity to touch, increased hair and nail growth in the affected region, joint pain, and color and temperature changes. A dystrophic stage may involve constant pain and swelling. The effected limb often feels cool to the touch and looks bluish. There is typically muscle stiffness and wasting (atrophy), as well as early bone loss (osteoporosis). These symptoms usually occur 3-6 months after development of the disorder. During an atrophic stage, the skin becomes cool and shiny, increased muscle stiffness and weakness occur, and symptoms may spread to another limb.

Other symptoms include: burning pain, extreme sensitivity to touch, skin color changes (red or bluish), skin temperature changes (hot or cold), joint pain, swelling (edema), frequent infections, muscle stiffness, muscle spasm, tremor, weakness, dermatitis, eczema, excessive sweating, and migraine headache. A compound described herein such as a TRPAl inhibitor can be useful not only in treating the pain associated with CRPS, but also in relieving many of these other symptoms including dermatitis, eczema, and migraines. There is currently no cure for CRPS, and thus treatment typically aims to relieve painful symptoms. Doctors may prescribe topical analgesics, antidepressants, corticosteroids, and opioids to relieve pain. However, to this point, no single drug or combination of drugs has produced consistent long-lasting improvement in symptoms. Other treatments may include physical therapy, sympathetic nerve block, spinal cord stimulation, and intrathecal drug pumps to deliver opioids and local anesthetic agents via the spinal cord. The goals of treatment are to control pain and to maintain as much mobilization of the affected limb as possible. An individualized treatment plan is designed, which often combines treatment modalities. Currently, physical therapy, medications, nerve blocks, and psychosocial support are used. A compound according to the present invention can be used instead of or in addition to one or more of the current treatment modalities. For example, a compound described herein (e.g., a TRPAl inhibitor) can be used as an alternative to current medications, but combined with physical therapy.

In addition to drug therapy, CRPS patients often receive physical therapy. A compound described herein such as a TRPAl inhibitor can be used in addition to physical therapy. Physical therapy may be important for helping retain range of motion and function in the affected limb. Appropriate pain management, for example using a compoud described herein, not only increases patient comfort, but also facilitates involvement in physical therapy.

Regardless of the particular combination of therapies used to manage pain in CRPS patients, psychological support is often critical. A compound described herein can be used in combination with psychological support.

The compounds disclosed herein can also be used to treat endometriosis and the pain associated therewith. Respiratory disorders

The compounds described herein are useful for the treatment or prevention of respiratory conditions. Such conditions affect the lung, pleural cavity, bronchial tubes, trachea, upper respiratory tract as well as the nerves and muscles involved in breathing. Respiratory diseases that may be treated with the compounds described herein include obstructive diseases such as chronic obstructive pulmonary disease (COPD), emphysema, chronic bronchitis, asthma (including asthma caused by industrial irritants), cystic fibrosis, bronchiectasis, bronchiolitis, allergic bronchopulmonary aspergillosis, and tuberculosis; restrictive lung disease including asbestosis, radiation fibrosis, hypersensitivity pneumonitis, infant respiratory distress syndrome, idiopathic pulmonary fibrosis, idiopathic pulmonary fibrosis, idiopathic interstial pneumonia sarcoidosis, eosinophilic pneumonia, lymphangioleiomyomatosis, pulmonary Langerhan's cell histiocytosis, and pulmonary alveolar proteinosis; respiratory tract infections including upper respiratory tract infections (e.g., common cold, sinusitis, tonsillitis, pharyngitis and laryngitis) and lower respiratory tract infections (e.g., pneumonia); respiratory tumors whether malignant (e.g., small cell lung cancer, non-small cell lung cancer, adenocarcinoma, squamous cell carcinoma, large cell undifferentiated carcinoma, carcinoid, mesothelioma, metastatic cancer of the lung, metastatic germ cell cancer, metastatic renal cell carcinoma) or benign (e.g., pulmonary hamartoma, congenital malformations such as pulmonary sequestration and congenital cystic adenomatoid malformation (CCAM)); pleural cavity diseases (e.g., empyema and mesothelioma); and pulmonary vascular diseases (e.g, pulmonary embolism such as thromboembolism, and air embolism (iatrogenic), pulmonary arterial hypertension, pulmonary edema, pulmonary hemorrhage, inflammation and damage to capillaries in the lung resulting in blood leaking into the alveoli. Other conditions that may be treated include disorders that affect breathing mechanics (e.g., obstructive sleep apnea, central sleep apnea, amyotrophic lateral sclerosis, Guillan-Barre syndrome, and myasthenia gravis). The present compounds can also be useful for treating, reducing, or preventing one or more symptoms associated with respiratory conditions including, for example, shortness of breath or dyspnea, cough (with or without the production of sputum), coughing blood (haemoptysis), chest pain including pleuritic chest pain, noisy breathing, wheezing, and cyanosis.

Dermatological Diseases or Disorders

Influx of calcium across plasma membrane of skin cells is a critical signaling element involved in cellular differentiation in the skin epidermis (Dotto, 1999 Crit Rev Oral Biol Med 10:442-457). Regulating or modulating the calcium entry pathway, and thus a critical control point for skin cell growth, can treat or prevent skin diseases or disorders that are characterized by epidermal hyperplasia, a condition in which skin cells both proliferate too rapidly and differentiate poorly. Such diseases include psoriasis, and basal and squamous cell carcinomas. Psoriasis, estimated to affect up to 7 million Americans, afflicts sufferers with mild to extreme discomfort, enhanced susceptibility to secondary infections, and psychological impact due to disfigurement of the affected areas (Lebwohl and AIi, 2001 J Am Acad Dermatol 45:487- 498). Basal cell carcinomas (BCC) and squamous cell carcinomas (SCC) of the skin represent at least one-third of all cancers diagnosed in the United States each year. More than 1 million new cases are reported annually and incidence is increasing. Despite being relatively non-aggressive, slow-growing cancers, BCCs are capable of significant local tissue destruction and disfigurement. SCCs are more aggressive and thus present even greater complications. Many dermatological disorders are accompanied by itch (pruritus). Pruritus and pain share many mechanistic similarities. Both are associated with activation of C-fibers, both are potentiated by increases in temperature and inflammatory mediators and both can be quelled with opiates. Decreasing neuronal excitability, particularly C-fiber excitability may alleviate pruritus associated with dialysis, dermatitis, pregnancy, poison ivy, allergy, dry skin, chemotherapy and eczema. Neurological or Neurodegenerative Diseases and Disorders

Neurodegenerative diseases and disorders include but are not limited to Alzheimer's disease (AD), Parkinson's disease, Huntington's disease, amyotrophic lateral sclerosis (ALS), and other brain disorders caused by trauma or other insults including aging.

Mechanisms associated with calcium signaling may be altered in many neurodegenerative diseases and in disorders resulting from brain injury. For example, fibroblasts or T-lymphocytes from patients with AD have consistently displayed an increase in Ca²⁺ release from intracellular stores compared to controls (Ito et al. (1994) Proc. Natl. Acad. Sci. U.S.A. 91 :534-538; Gibson et al. (1996) Biochem. Biophys. ACTA 1316:71 -77; Etchenberrigaray et al. (1998) Neurobiology of Disease, 5:37-45). Consistent with these observations, mutations in presenilin genes (PSl or PS2) associated with familial AD (FAD) have been shown to increase InsP3-mediated Ca²⁺ release from internal stores (Guo et al. (1996) Neuro Report, 8:379-383; Leissring et al. (1999) J. Neurochemistry, 72:1061 -1068; Leissring et al. (1999) J. Biol. Chem. 274(46):32535-32538; Leissring et al. (2000) J. Cell Biol. 149(4):793-797; Leissring et al.

(2000) Proc. Natl. Acad. Sci. U.S.A. 97(15):8590-8593). Furthermore, mutations in PSl or PS2 associated with an increase in amyloidogenic amyloid β peptide generation in AD are reported to be associated with a decrease in intracellular calcium level (Yoo et al. (2000) Neuron, 27(3):561- 572). Experimental traumatic brain injury has been shown to initiate massive disturbances in

Ca²⁺ concentrations in the brain that may contribute to further neuronal damage. Intracellular Ca ⁺ may be elevated by many different ion channels. It has been further shown that channel blockers may be beneficial in the treatment of neurological motor dysfunction when administered in the acute posttraumatic period (Cheney et al. (2000) J. Neurotrauma. 17(1):83- 91). Inflammatory Diseases and Disorders

Compositions and methods provided herein may also be used in connection with treatment of inflammatory diseases. These diseases include but are not limited to asthma, chronic obstructive pulmonary disease, rheumatoid arthritis, osteoarthritis, inflammatory bowel disease, glomerulonephritis, neuroinflammatory diseases such as multiple sclerosis, and disorders of the immune system.

The activation of neutrophils (PMN) by inflammatory mediators is partly achieved by increasing cytosolic calcium concentration ([Ca²⁺],). Certain calcium channel-mediated calcium influx in particular is thought to play an important role in PMN activation. It has been shown that trauma increases PMN store-operated calcium influx (Hauser et al. (2000) J. Trauma Injury Infection and Critical Care 48 (4):592-598) and that prolonged elevations of [Ca²⁺], due to enhanced store-operated calcium influx may alter stimulus-response coupling to chemotaxins and contribute to PMN dysfunction after injury. Modulation of PMN [Ca²⁺], through store- operated calcium channels might therefore be useful in regulating PMN-mediated inflammation and spare cardiovascular function after injury, shock or sepsis (Hauser et al. (2001) J. Leukocyte Biology 69 (l):63-68).

Peripheral neuropathy, for example diabetic neuropathy, is a particular condition that involves both a neuronal and an inflammatory component. Without being bound by a mechanistic theory, the TRPAl antagonists of the invention may be useful in treating peripheral neuropathies including, but not limited to, diabetic neuropathy. In addition to their use in the treatment of peripheral neuropathies (e.g., reducing inflammation), the subject inhibitors may also be useful in reducing the pain associated with peripheral neuropathy.

Neurogenic inflammation often occurs when neuronal hyperexcitability leads to the release of peptides that trigger inflammation. These peptides include substance P and CGRP. Blocking TRPAl would reduce neuronal activity and thus could block neurogenic inflammation. Pancreatitis is an inflammation of the pancreas. The pancreas is a large gland behind the stomach and close to the duodenum. Normally, digestive enzymes do not become active until they reach the small intestine, where they begin digesting food. But if these enzymes become active inside the pancreas, they start "digesting" the pancreas itself. Acute pancreatitis is usually, although not exclusively, caused by gallstones or by alcohol abuse. Acute pancreatitis usually begins with pain in the upper abdomen that may last for a few days. The pain may be severe and may become constant. The pain may be isolated to the abdomen or it may reach to the back and other areas. Sometimes, and for some patients, the pain is sudden and intense. Other times, or for other patients, the pain begins as a mild pain that worsens after eating. Someone with acute pancreatitis often looks and feels very sick. Other symptoms may include swollen and tender abdomen, nausea, vomiting, fever, and rapid pulse. Severe cases of acute pancreatitis may cause dehydration and low blood pressure, and may even lead to organ failure, internal bleeding, or death.

During acute pancreatitis attacks, the blood levels of amylase and lipase are often increased by at least 3-fold. Changes may also occur in blood levels of glucose, calcium, magnesium, sodium, potassium, and bicarbonate.

The current treatment depends on the severity of the attack. Treatment, in general, is designed to support vital bodily functions, manage pain, and prevent complications. Although acute pancreatitis typically resolved in a few days, pain management during an attack is often required. The compounds disclosed herein can be used to relieve the pain associated with acute pancreatitis.

Chronic pancreatitis - If injury to the pancreas continues, chronic pancreatitis may develop. Chronic pancreatitis occurs when digestive enzymes attack and destroy the pancreas and nearby tissues, causing scarring and pain. Chronic pancreatitis may be caused by alcoholism, or by blocked, damaged, or narrowed pancreatic ducts. Additionally, hereditary factors appear to influence the disease, and in certain cases, there is no identifiable cause (so called idiopathic pancreatitis).

Most people with chronic pancreatitis have abdominal pain. The pain may get worse when eating or drinking, spread to the back, or become constant and disabling. Other symptoms include nausea, vomiting, weight loss, and fatty stools. Relieving pain is the first step in treating chronic pancreatitis. Once the pain has been managed, a high carbohydrate and low fat dietary plan is put in place. Pancreatic enzymes may be used to help compensate for decrease enzyme production from the injured pancreas. Sometimes insulin or other drugs are needed to control blood glucose.

Although pain is typically managed using drug therapy, surgery may be necessary to relieve pain. Surgery may be necessary to drain an enlarged pancreatic duct or even to removing a portion of a seriously injured pancreas. Pain is frequently present with chronic pancreatitis. For example, pain is present for approximately 75% of patients with alcoholic chronic pancreatitis, 50% of patients with late- onset idiopathic chronic pancreatitis, and 100% of patients with early-onset idiopathic chronic pancreatitis (DiMagno, 1999, Gastroenterology 116(5): 1252- 1257). A minority of patients with pain have readily identifiable lesions which are relatively easy to treat surgically or endoscopically. In other patients, pain is often thought to result from a variety of causes, including elevated intrapancreatic pressure, ischemia, and fibrosis. Without being bound by theory, however, these phenomena are not likely the underlying cause of the pain. Rather, pain may result from a background of neuronal sensitization induced by damage to the perineurium and subsequent exposure of the nerves to mediators and products of inflammation.

Given the importance of effective pain management in patients with chronic pancreatitis, additional therapies for treating painful symptoms are important and useful. The compounds disclosed herein can be used to manage the pain associated with chronic pancreatitis; they can be used alone or as part of an overall therapeutic treatment plan to manage patients with chronic pancreatits. For example, the compounds can be administered with pancreatic enzymes and/or insulin as part of a therapeutic regimen designed to manage patients with chronic pancreatitis. Cancer and Other Proliferative Diseases

Compositions and methods provided herein may also be used in connection with treatment of malignancies, including, but not limited to, malignancies of lymphoreticular origin, bladder cancer, breast cancer, colon cancer, endometrial cancer, head and neck cancer, lung cancer, melanoma, ovarian cancer, prostate cancer and rectal cancer, in addition to skin cancers described above. Intracellular calcium level may play an important role in cell proliferation in cancer cells (Weiss et al. (2001) International Journal of Cancer 92 (6):877-882). In addition, pain associated with cancer or with cancer treatment is a significant cause of chronic pain. Cancers of the bone, for example, osteosarcoma, are considered exceptionally painful, and patients with advanced bone cancer may require sedation to tolerate the intense and persistent pain. Accordingly, TRPAl antagonists of the invention represent a significant possible therapeutic for the treatment of pain, for example, the pain associated with cancer or with cancer treatment. Given that TRPAl is differentially expressed in transformed cells, a compound described herein (e.g., a compound that blocks TRPAl) may also affect the proliferation of transformed cells and thus be a useful way to slow the disease (see Jaquemar et al. (1999) JBC 274(11): 7325-33). Thus a compound described herein (e.g., a TRPAl antagonist) could alleviate both the cause and symptoms of cancer pain.

Cancer treatments are not only painful, but they may even be toxic to healthy tissue. Some chemotherapeutic agents can cause painful neuropathy. Accordingly, the compounds disclosed herein could represent a significant possible therapeutic for the treatment of the pain and/or inflammation associated with cancer treatments that cause neuropathy. A major function of prostaglandins is to protect the gastric mucosa. Included in this function is the modulation of intracellular calcium level in human gastric cells which plays a critical role in cell proliferation. Consequently, inhibition of prostaglandins by nonsteroidal antiinflammatory drugs (NSAIDs) can inhibit calcium influx in gastric cells (Kokoska et al. (1998) Surgery (St Louis) 124 (2):429-437). The NSAIDs that relieve inflammation most effectively also produce the greatest gastrointestinal damage (Canadian Family Physician, January 1998, p. 101). Thus, the ability to independently modulate calcium channels in specific cell types may help to alleviate such side effect of anti-inflammatory therapy. Additionally or alternatively, administration of a compound disclosed herein may be used in combination with NSAIDs, thus promoting pain relief using reduced dosage of NSAJDs. Incontinence

Incontinence is a significant social and medical problem affecting both men and women. Incontinence has many causes including, but not limited to, age, pregnancy, radiation exposure, surgery, injury, cancer, enlargement of the prostatic, prostatic hyperplasia, and diseases of the bladder or musculature that supports the urethra. The invention contemplates methods for treating incontinence due to any of the foregoing, as well as incontinence of unknown cause or continence due to anxiety, stress, or depression.

In certain embodiments, the compounds disclosed herein are used to reduce bladder hyperactivity by decreasing the activity of the neurons that innervate the bladder. In certain embodiments, incontinence is accompanied by pain. For example, incontinence incident to bladder cystitis or incontinence incident to an injury may be accompanied by pain. When incontinence is accompanied by pain, the compound may be administered to treat both incontinence and to reduce pain.

Animal models of incontinence are often associated with an increase in the frequency of spontaneous action potentials and a chronic depolarization of the smooth muscle cells. Evidence suggests that a non-selective cation current could lead to this depolarization. Since TRPAl mRNA is expressed in neurons that innervate bladder, blocking TRPAl might be an effective treatment for incontinence. In addition, TRPAl is activated by stimulation of the muscarinic type 1 acetylcholine receptor (Ml, see Jordt et al. (2004) Nature 427:260-265). Antimuscarininc agents are well known drugs for the treatment of condition such as overactive bladder. Thus blocking TRPAl , a downstream target of the Ml receptor might alleviate such conditions without the side effects that are associated with muscarinic antagonists. Temperature Regulation

Because of the effects of ion flux on arterial tension and relaxation, the subject compounds can also be used to affect thermal sensitivity. Furthermore, given that TRPAl channels are thermal responsive channels involved in the reception and sensation of cold stimuli, TRPAl antagonists can be used to modulate the sensation of cool, cold and decreased temperatures that often accompany pain. Hypertension

Blockers of voltage-gated calcium channels belong to a class of medications originally developed to treat hypertension. Such blockers inhibit the movement of calcium into the muscle cells of the heart and arteries. Because calcium is needed for these muscles to contract, such blockers lower blood pressure by decreasing the force of cardiac contractile response and relaxing the muscle walls of the arteries. Although TRPAl is not a voltage-gated calcium channel, it is still instrumental in regulating calcium homeostasis, as well as the balance of other ions, in cells and tissues. Oral mucositis

Oral mucositis, also known as stomatitis, is a common complication of many cancer treatments. Patients receiving systemic chemotherapy and/or local radiotherapy often develop extremely painful ulcers of the oral mucosa. This side effect is not limited to patients suffering from cancers of the head and neck, but rather is a debilitating side effect afflicting approximately 40% of all chemotherapy patients (Prevention and Treatment of Oral Mucositis in Cancer

Patients, 1998, Best Practice: 2, pages 1-6.)

Oral mucositis is extremely painful. Additionally, oral mucositis interferes with proper nutrition and hydration of cancer patients. Given the already compromised status of patients undergoing chemotherapy and/or radiotherapy, further interference with nutrition and hydration may seriously undermine patient health. Furthermore, these ulcers present an increased risk of infection. This risk is particularly acute in patients with compromised immune systems.

Examples of patients at particular risk of developing an opportunistic infection are patients whose treatment included removal of one or more lymph nodes, patients who previously received high-dose chemotherapy in preparation for a bone marrow or stem cell transplant, and patients with an underlying immunosuppressive disorder (e.g., HIV or hepatitis).

Canker sores

Canker sores, also known as aphthous ulcers (aphthae), may be relatively small and out- of-sight. However, they are often painful, persistent and annoying. Canker sores are shallow ulcers in the mouth that can make eating and talking uncomfortable. They may occur on the tongue, soft palate, inside the cheek or lip, or at the base of the gums. Canker sores differ from cold sores in that they occur on the internal soft tissues of the mouth and aren't contagious.

Conversely, cold sores almost always start out on the lips and don't often spread to the soft tissues of the mouth. In addition, cold sores are caused by a form of the herpes virus, making them extremely contagious. The compounds disclosed herein could be used to treat the pain of canker sores.

Dental/tooth abscess

Infection or decay can lead to an abscess. An abscess may have serious dental and medical consequences. For example, a severe infection caused by a dental abscess may lead to a sinus or systemic infection. Furthermore, an abscess may lead to the need to extract one or more teeth. Extraction may be necessary due to significant tooth decay, or because the infection is too severe to fully treat in the presence of the offending tooth.

Regardless of the ultimate outcome, a dental abscess may be extremely painful. Not only is the pain uncomfortable, but it may interfere with proper nutrition and hydration. Methods and compositions, such as those disclosed herein, for reducing the pain associated with dental abscess would provide significant benefits for their management. Gastroesophageal Reflux Disease

Gastroesophageal reflux disease, or GERD, occurs when the lower esophageal sphincter (LES) does not close properly and stomach contents leak back into the esophagus. The LES is a ring of muscle at the bottom of the esophagus that acts like a valve between the esophagus and stomach. When refluxed stomach acid touches the lining of the esophagus, it causes a burning sensation in the chest or throat. This is often experienced as heartburn. The refluxed fluid may even be tasted in the back of the mouth, a sensation commonly referred to as acid indigestion. Although occasional heartburn is uncommon and not necessarily indicative of GERD, heartburn that occurs more than twice a week may be a sign of GERD. In addition to the discomfort of heartburn and indigestion, GERD may lead to other serious health problems. For example, over time, acid refluxed to the back of the throat can lead to oral sores, lesions, or ulcers in the mouth, gums, tongue, throat, or lips. The lesions can cause significant pain, can interfere with nutrition and hydration, and can leave a person vulnerable to infection.

Administration of compounds according to the present invention, may be useful in treating oral pain from lesions caused by GERD; they may be used as part of a treatment regimen where the compound is administered to help manage the discomfort of the oral lesion, while other agents or therapeutics interventions are used to manage the GERD. Gingivostomatitis

Gingivostomatitis is a disorder involving sores on the mouth and gums that result from a viral infection. Gingivostomatitis is characterized by inflammation of the gums and mucosa and multiple oral ulcers. The inflammation and ulcers are caused by viral infections, particularly those that cause common childhood illness such as herpes virus (cold sores and acute herpetic stomatitis), and Coxsackie viruses (hand, foot and mouth disease and herpangina). These viruses cause shallow ulcers with a grayish or yellowish base and a slightly red margin, on the tissues of the gums (gingiva), the lining of the cheeks (buccal mucosa), or other soft tissues of the mouth. Although this condition can occur in patients of any age, it is particularly common in children.

The oral ulcers casued by these viruses can be very painful. The ulcers are often accompanied by a fever. Overall, the condition can take several weeks to resolve. The recognized treatments for gingivostomatitis focus on reducing the pain caused by the oral ulcers. This is particularly important for children who may refuse food or liquids because of their discomfort, thus making them especially susceptible to dehydration. Compounds disclosed herein can be used to treat the pain associated with these oral ulcers. Oral thrush

Oral thrush is a fungal infection generally caused by the yeast fungus, Candida albicans, in the mucous membranes of the mouth. Strictly speaking, thrush is only a temporary Candida infection in the oral cavity of babies. However, the term is used generally to refer to fungal infections in the mouths and throats of children and adults.

Candida is present in the oral cavity of almost half of the population. For example, everyone who wears dentures has Candida, without necessarily suffering any ill effects. Generally, Candida does not create problems until there is a change in the chemistry of the oral cavity such that the growth of Candida is favored over the other microorganisms that typically inhabit the mouth and throat. Changes in oral chemistry sufficient to permit the growth of Candida may occur as a side effect to taking antibiotics or chemotherapeutics. Overall patient health may also influence the chemistry of the mouth. HIV infection, diabetes, malnutrition, age, and immunodeficiency are exemplary conditions that can shift oral chemistry enough to permit the overgrowth of Candida in the mouth and throat.

In addition to shifts in oral chemistry, people whose dentures don't fit well can sustain breaks in the mucous membranes in their mouth. These breaks provide an opportunity for Candida infection in the mouth and lips. Thrush causes white, cream-colored, or yellow spots in the mouth. The spots are slightly raised. If these spots are scraped they tend to bleed. Thrush can be very uncomfortable, and may cause a burning sensation in the mouth and throat. The discomfort may interfere with hydration and nutrition. Furthermore, the discomfort may interfere with proper oral hygiene such as brushing and flossing. Standard treatment of thrush is by administration of anti-fungal agents. These agents can be administered directly to the mouth, for example, in the form of pastilles that are sucked or oral suspensions that are held in the mouth before swallowing. Examples include nystatin (e.g., Nystan oral suspension), amphotericin (e.g., Fungilin lozenges) or miconazole (e.g., Daktarin oral gel). In addition to standard anti-fungal therapy, compounds disclosed herein can be administered to manage the pain and discomfort associated with thrush. Glossitis Glossitis is an abnormality of the tongue that results from inflammation. Glossitis occurs when there is acute or chronic inflammation of the tongue. It causes the tongue to swell and change color. Finger-like projections on the surface of the tongue (papillae) are lost, causing the tongue to appear smooth. Glossitis has a number of causes including, but not limited to, the following: bacterial infections; viral infections (including oral herpes simplex); injury or trauma; exposure to irritants (e.g., tobacco, alcohol, hot foods, spices); allergic reactions; vitamin or mineral deficiencies (e.g., iron deficiency anemia, pernicious anemia and other B-vitamin deficiencies); or as a side effect of other diseases or disorders.

The symptoms of glossitis include swelling, soreness, and tenderness of the tongue. Additionally, the tongue often changes appearance, becoming smooth and dark red in color. As a consequence of the swelling and discomfort, glossitis often makes chewing, swallowing, and speaking diffcult.

The typical treatment for glossitis depends on the underlying cause of the inflammation.

Regardless of the particular antibiotics, antiinflammatories, or anti-viral agents that may be administered to combat the underlying cause of glossitis, compounds according to the present invention may be administered to decrease the pain and discomfort associated with glossitis.

Decreasing the pain associated with glossitis is especially important when it interferes with proper nutrition and hydration, or when it interferes with or prevents proper oral hygiene.

Cutaneous diseases Oral ulcers may result from any of a number of cutaneous diseases. For example, lichen planus, pemphigus, pemphigoid, and erythema multiforme may lead to oral ulcers. Such oral ulcers may cause significant pain that can be treated using the compounds disclosed herein.

Reduction of pain may help facilitate healing. This is especially important for patients with pemphigus and pemphigoid who develop oral ulcers. Such patients are already immunosuppressed, and may thus be more susceptible to opportunistic infections from lesions in the mouth.

Gastrointestinal diseases

Oral ulcers may result from any of a number of gastrointestinal diseases. Conditions which interfere with proper digestion, management and flow of stomach and other digestive acids, motility, and elimination may lead to oral ulcers and other lesions. In some instances, the oral ulcers are the results of acids or partially digested food refluxing into the esophagus. In other instances, the oral ulcers result from frequent vomiting. In still other instances, oral ulcers occur due to vitamin deficiency, mineral deficiency or other nutritional deficiency secondary to the gastrointestinal disease. In still other instances, oral ulcers are part of the complex etiology that characterizes the gastrointestinal disease. Oral ulcers resulting from or experienced as part of a gastrointestinal disease may be extremely painful. They may undermine proper nutrition and hydration for a patient whose underlying gastrointestinal disease may already impose multiple limitations on diet.

Accordingly, methods and compositions for decreasing the discomfort and pain associated with these oral ulcers offer substantial benefits for patients with an underlying gastrointestinal condition.

Exemplary gastrointestinal conditions which may lead to oral inflammation, lesions, or ulcers include, but are not limited to, Crohn's disease, ulcerative colitis, irritable bowel syndrome, celiac sprue, and dermatitis herpetiformis. The primary symptoms of these conditions may be managed with diet, stress management, and medications. The compounds disclosed herein may be used to help manage the pain and discomfort of oral inflammation, lesions, or ulcers caused by any of these gastrointestinal conditions.

Rheumatoid diseases

A consequence of several rheumatoid diseases is oral ulcers. For example, lupus,

Behcet's syndrome, Sweet's syndrome, and Reiter's disease may all lead to oral ulcers. Such oral ulcers may cause significant mouth pain that can be treated using the compounds disclosed herein.

Sjogren's Syndrome

Dry mouth is a common symptom associated with Sjogren's syndrome. Dry mouth is caused by a decrease in the production of saliva. Saliva is an essential body fluid for protection and preservation of the oral cavity and oral functions. Although saliva is mostly water, it also contains over 60 substances which serve the following important functions: protect, lubricate and cleanse the oral mucosa; aid chewing, swallowing and talking; protect the teeth against decay; protect the mouth, teeth, and throat from infection by bacteria, yeasts, and viruses; support and facilitate our sense of taste. Given the important functions of saliva, decreased salivation can lead to many problems.

If the condition persists for months or years, a patient may develop oral complications such as difficulty swallowing, severe and progressive tooth decay, oral infections (particularly fungal), or combinations of these. Many of the conditions can cause discomfort, in their own right, and may also lead to oral lesions or ulcers.

Several medications are available to help increase salivary secretion in patients with dry mouth. Pilocarpine (Salagen^®) and cevimeline (Evoxac^®) reduce symptoms of dry mouth and increase salivary secretion. However, these drugs don't prevent tooth decay or treat the oral pain associated with the symptoms or effects of dry mouth. Compounds disclosed herein can be used to treat the pain associated with dry mouth. Vitamin or mineral deficiencies In some instances, vitamin or mineral deficiencies may lead to ulcers or other sores in the mouth. For example, deficiency in vitamin C may lead to the oral lesions characteristic of scurvy. Deficiencies in vitamins Bl, B2, B6, or B 12 may also lead to oral lesions. Additionally, deficiencies in zinc, folic acid, iron, selenium, or calcium may lead to oral lesions.

In certain embodiments, a vitamin or mineral deficiency is a precipitating factor leading to a canker sore. However, a vitamin or mineral deficiency may also lead to other types of oral ulcers and lesions. Regardless of the nature of the lesion, compounds disclosed herein can be used to help manage the associated pain. Allergies

Allergies can sometimes lead to canker sores and other oral lesions. Oral lesions due to an allergy may be more likely when a person's oral tissues come into contact with the causative allergen. However, contact between the allergen and oral tissue is not necessarily required to produce an oral lesion. Exemplary allergens that can lead to oral lesions include food allergens such as fruits and vegetables (e.g., strawberries, lemons, oranges, pineapples, apples, figs, tomatoes); shellfish; chocolate; nuts; dairy (e.g., milk and cheese); cereal grains (e.g., buckwheat, wheat, oats, rye, barley, gluten protein found in grains); additives (e.g., cinnamonaldehyde (a flavoring agent), benzoic acid (a preservative); toothpastes (e.g., some people have a sensitivity to sodium laurel sulfate found in certain toothpastes and mouthwashes); nonsteroidal anti-inflammatory drugs (NSAIDs; some people have a sensitivity leading to canker sores in response to this class of drug). Other conditions and injuries Other conditions include psoriasis and basal cell and squamous cell cariconomas, a neurodegenerative disease or disorder, e.g., Alzheimer's disease (AD), Parkinson's disease, Huntington's disease, amyotrophic lateral sclerosis (ALS), and other brain disorders caused by trauma or other insults including aging, inflammatory bowel disease, glomerulonephritis, neuroinflammatory diseases, multiple sclerosis, and disorders of the immune system), cancer (e.g. liposarcoma) or other proliferative disease, kidney disease and liver disease, a metabolic disorder such as diabetes. Additional conditions include metabolic diseases and disorders including obesity and diabetes; liver and kidney diseases and disorders; malignancies including cancers; aging-related disorders; ATP-related diseases or disorders including epilepsy, cognition, emesis, pain (e.g., migraine), asthma, peripheral vascular disease, irritable bowel syndrome, cystitis, depression, aging-associated degenerative diseases, urinary incontinence, premature ejaculation, cystic fibrosis, diabetes, contraception and sterility, and wound healing (see, for example, Foresta et al. (1992) J. Biol. Chem. 257:19443-19447; Wang et al. (1990) Biochim. Biophys. Res. Commun. 166:251-258; Burnstock and Williams, (2000) J. Pharmacol. Exp. Ther. 295: 862-869; and Burnstock, Pharmacol Rev (2006) 58:58-86).

Combination Therapy

The subject compounds can be used alone or in combination with other pharmaceutically active agents. Examples of such other pharmaceutically active agents include, but are not limited to, anti-inflammatory agents (e.g., NSAIDS, bradykinin receptor antagonists, hormones and autacoids such as corticosteroids), anti-acne agents (e.g., retinoids), anti-wrinkle agents, anti- scarring agents, anti-incontinence agents (such as Ml -receptor antagonists) anti -emetics (such as NKl antagonists), anti-psoriatic agents, antacids, anti-proliferative agents (e.g., anti-eczema agents, anti-cancer), anti-fungal agents, anti-viral agents, anti-septic agents (e.g., antibacterials), local anaesthetics, anti-migraine agents, keratolytic agents, hair growth stimulants, hair growth inhibitors, and other agents used for the treatment of skin diseases or conditions. Certain active agents belong to more than one category.

In certain embodiments, a compound of the invention is conjointly administered with an analgesic. Suitable analgesics include, but are not limited to, opioids, glucocorticosteroids, non- steroidal anti-inflammatories, naphthylalkanones, oxicams, para-aminophenol derivatives, propionic acids, propionic acid derivatives, salicylates, fenamates, fenamate derivatives, pyrozoles, and pyrozole derivatives. Examples of such analgesic compounds include, but are not limited to, codeine, hydrocodone, hydromorphone, levorpharnol, morphine, oxycodone, oxymorphone, butorphanol, dezocine, nalbuphine, pentazocine, etodolac, indomethacin, sulindac, tolmetin, nabumetone, piroxicam, acetaminophen, fenoprofen, flurbiprofen, ibuprofen, ketoprofen, naproxen, diclofenac, oxaprozin, aspirin, diflunisal, meclofenamic acid, mefanamic acid, prednisolone, and dexamethasone. Preferred analgesics are non-steroidal antiinflammatories and opioids (preferably morphine).

In some embodiments, the compounds disclosed herein can be admininstered in conjunction with a therapeutic whose administration causes pain. For example, a compound described herein can be administered in conjunction with an anesthetic, to reduce the pain caused by the administration of the anaesthetic. A compound described herein can also be administered in conjunction with a chemotherapeutic agent, to reduce the pain caused by administration of the chemotherapeutic agent.

In certain embodiments, a compound of the invention is conjointly administered with a non-steroidal anti-inflammatory. Suitable non-steroidal anti-inflammatory compounds include, but are not limited to, piroxicam, diclofenac, etodolac, indomethacin, ketoralac, oxaprozin, tolmetin, naproxen, flubiprofen, fenoprofen, ketoprofen, ibuprofen, mefenamic acid, sulindac, apazone, phenylbutazone, aspirin, celecoxib and rofecoxib.

In certain embodiments, a compound of the invention is conjointly administered with an antiviral agent. Suitable antiviral agents include, but are not limited to, amantadine, acyclovir, cidofovir, desciclovir, deoxyacyclovir, famciclovir, foscamet, ganciclovir, penciclovir, azidouridine, anasmycin, amantadine, bromovinyldeoxusidine, chlorovinyldeoxusidine, cytarbine, didanosine, deoxynojirimycin, dideoxycitidine, dideoxyinosine, dideoxynucleoside, edoxuidine, enviroxime, fiacitabine, foscamet, fialuridine, fjuorothymidine, floxuridine, hypericin, interferon, interleukin, isethionate, nevirapine, pentamidine, ribavirin, rimantadine, stavirdine, sargramostin, suramin, trichosanthin, tribromothymidine, trichlorothymidine, vidarabine, zidoviridine, zalcitabine 3-azido-3-deoxythymidine, 2',3'-dideoxyadenosine (ddA), 2',3'-dideoxyguanosine (ddG), 2',3'-dideoxycytidine (ddC), 2',3'-dideoxythymidine (ddT), 2'3'- dideoxy-dideoxythymidine (d4T), 2'-deoxy-3'-thia-cytosine (3TC or lamivudime), 2',3'-dideoxy- 2'-fluoroadenosine, 2',3'-dideoxy-2'-fluoroinosine, 2',3'-dideoxy-2'-fluorothymidine, 2',3'- dideoxy-2'-fluorocytosine, 2'3'-dideoxy-2',3'-didehydro-2'-fluorothymidine (Fd4T), 2'3'-dideoxy- 2'-beta-fluoroadenosine (F-ddA), 2'3'-dideoxy-2'-beta-fluoro-inosine (F-ddl), and 2',3'-dideoxy- 2'-beta-flurocytosine (F-ddC), trisodium phosphomonoformate, trifluorothyraidine, 3'azido- 3'thymidine (AZT), dideoxyinosine (ddl), and idoxuridine.

In certain embodiments, a compound of the invention is conjointly administered with an antibacterial agent. Suitable antibacterial agents include, but are not limited to, amanfadine hydrochloride, amanfadine sulfate, amikacin, amikacin sulfate, amoglycosides, amoxicillin, ampicillin, amsamycins, bacitracin, beta-lactams, candicidin, capreomycin, carbenicillin, cephalexin, cephaloridine, cephalothin, cefazolin, cephapirin, cephradine, cephaloglycin, chilomphenicols, chlorhexidine, chloshexidine gluconate, chlorhexidine hydrochloride, chloroxine, chlorquiraldol, chlortetracycline, chlortetracycline hydrochloride, ciprofloxacin, circulin, clindamycin, clindamycin hydrochloride, clotrimazole, cloxacillin, demeclocycline, diclosxacillin, diiodohydroxyquin, doxycycline, ethambutol, ethambutol hydrochloride, erythromycin, erythromycin estolate, erhmycin stearate, farnesol, floxacillin, gentamicin, gentamicin sulfate, gramicidin, giseofulvin, haloprogin, haloquinol, hexachlorophene, iminocylcline, iodochlorhydroxyquin, kanamycin, kanamycin sulfate, lincomycin, Hneomycin, lineomycin hydrochoride, macrolides, meclocychne, methacycline, methacycline hydrochloride, methenine, methenamine hippurate, methenamine mandelate, methicillin, metonidazole, miconazole, miconazole hydrochloride, minocycline, minocycline hydrochloride, mupirocin, nafcillin, neomycin, neomycin sulfate, netimicin, netilmicin sulfate, nitrofurazone, norfloxacin, nystatin, octopirox, oleandomycin, orcephalosporins, oxacillin, oxyteacline, oxytetracycline hydrochloride, parachlorometa xylenol, paromomycin, paromomycin sulfate, penicillins, penicillin G, penicillin V, pentamidine, pentamidine hydrochloride, phenethicillin, polymyxins, quinolones, streptomycin sulfate, tetracycline, tobramycin, tolnaftate, triclosan, trifampin, rifamycin, rolitetracycline, spectinomycin, spiramycin, struptomycin, sulfonamide, tetracyclines, tetracycline, tobramycin, tobramycin sulfate, triclocarbon, triclosan, trimethoprim- sulfamethoxazole, tylosin, vancomycin, and yrothricin.

Examples of retinoids that be administered with the subject compounds, e.g., where the TRPAl inhibitor can be used to reduce the pain and/or inflammatory effect of the retinoid, include, but are not limited to, compounds such as retinoic acid (both cis and trans), retinol, adapalene, vitamin A and tazarotene. Retinoids are useful in treating acne, psoriasis, rosacea, wrinkles and skin cancers and cancer precursors such as melanoma and actinic keratosis. Similarly, the subject compounds can be used in conjunction with keratolytic agents include benzoyl peroxide, alpha hydroxyacids, fruit acids, glycolic acid, salicylic acid, azelaic acid, trichloroacetic acid, lactic acid and piroctone.

The subject compounds can be used with anti-acne agents, anti-eczema agents and anti- psoratic agents. Compounds particlarly useful in treating acne include azelaic acid (an aliphatic diacid with antiacne properties), anthralin (a diphenolic compound with antifungal and antipsoriatic properties), and masoprocol (nordihydroguaiaretic acid, a tetraphenolic compound with antioxidant properties, also useful in the treatment of actinic keratosis) and analogs thereof (such as austrobailignan 6, oxoaustrobailignan 6, 4'-O-methyl-7,7'-dioxoaustrobailignan 6, macelignan, demethyldihydroguaiaretic acid, 3,3',4-trihydroxy-4'-methoxylignan, Saururenin, 4- hydroxy-3,3',4'-trimethoxylignan, and isoanwulignan). Anti-eczema agents include pimecrolimus and tacrolimus. Anti -psoriatic active agents suitable for use in the present invention include retinoids (including isomers and derivatives of retinoic acid, as well as other compounds that bind to the retinoic acid receptor, such as retinoic acid, acitretin, 13-cis-retinoic acid (isotretinoin), 9-cis-retinoic acid, tocopheryl-retinoate (tocopherol ester of retinoic acid (trans- or cis-)), etretinate, motretinide, l-(13-cis-retinoyloxy)-2-propanone, l-(13-cis- retinoyloxy)-3-decanoyloxy-2-propanone, l,3-bis-(13-cis-retinoyloxy)-2-propanone, 2-(13-cis- retinoyloxy)-acetophenone, 13-cis-retinoyloxymethyl-2,2-dimethyl propanoate, 2-(13-cis- retinoyloxy)-n-methyl-acetamide, l-(13-cis-retinoyloxy)-3-hydroxy-2-propanone, l-(13-cis- retinoyloxy)-2,3-dioleoylpropanone, succinimdyl 13-cis-retinoate, adapalene, and tazarotene), salicylic acid (monoammonium salt), anthralin, 6-azauridine, vitamin D derivatives (including but not limited to Rocaltrol (Roche Laboratories), EB 1089 (24α,26α,27α-trihomo-22,24-diene- 101,25-(OH)₂-D₃), KH 1060 (20-epi-22-oxa-24α,26α,27α-trihomo-lα,25-(OH)₂-D₃), MC 1288, GS 1558, CB 1093, 1 , 25-(OH)₂- 16-ene-D₃, 1 ,25-(OH)₂- 16-ene-23-yne-D₃, and 25-(OH)2- 16- ene-23-yne-D₃, 22-oxacalcitriol; 1 α-(OH)D₅ (University of Illinois), ZK 161422 and ZK 157202 (Institute of Medical Chemistry-Schering AG), alfacalcidol, calcifediol, calcipotriol (calcipotriene), maxacalcitriol, colecalciferol, doxercalciferol, ergocalciferol, falecalcitriol, lexacalcitol, maxacalcitol, paricalcitol, secalciferol, seocalcitol, tacalcitol, calcipotriene, calcitriol, and other analogs as disclosed in U.S. Patent No. 5,994,332), pyrogallol, and tacalcitol. The compounds disclosed herein can also be administered with vitamins and derivatives thereof including Vitamin A, ascorbic acid (Vitamin C), alpha-tocopherol (Vitamin E), 7- dehydrocholesterol (Vitamin D), Vitamin K, alpha-lipoic acid, lipid soluble anti-oxidants, and the like. They can also be used with skin protectants, such allantoin and esculin.

In addition to TRPAl , other TRP channels have been implicated in pain reception and/or sensation. For example, certain TRPM channels including TRPM8 have been implicated in the reception and/or sensation of pain. Accordingly, in certain embodiments, the methods of the present invention include treating pain by administering (i) a combination of a selective TRPAl antagonist and a selective TRPM8 antagonist; (ii) a combination of a selective TRPAl antagonist, a selective TRPM8 antagonist, and one or more of a selective TRPVl and/or TRPV3 antagonist; (iii) a cross-TRP inhibitor that antagonizes a function of TRPAl and TRPM8; or (iv) a pan inhibitor that antagonizes a function of TRPAl , TRPM8, and one or more of TRPV 1 and TRPV3.

In certain embodiments, a compound of the invention is conjointly administered with one or more additional compounds that antagonize the function of a different channel. By way of example, a compound of the invention may be conjointly administered with one or more compounds that antagonize TRPVl, TRPM8, and/or TRPV3. The compound(s) that antagonize TRPVl, TPRM8, or TRPV3 may be selective for TRPVl, TRPM8 or TRPV3 (e.g., inhibit TRPVl or TRPV3 10, 100, or 1000 fold more strongly than TRPAl). Alternatively, the compound(s) that antagonize TRPVl or TRPV3 may cross react with other TRP channels.

Pharmaceutical Compositions

While it is possible for a compound disclosed herein to be administered alone, it is preferable to administer the compound as a pharmaceutical formulation, where the compound is combined with one or more pharmaceutically acceptable excipients or carriers. The compounds disclosed herein may be formulated for administration in any convenient way for use in human or veterinary medicine. In certain embodiments, the compound included in the pharmaceutical preparation may be active itself, or may be a prodrug, e.g., capable of being converted to an active compound in a physiological setting.

The phrase "pharmaceutically acceptable" is employed herein to refer to those compounds, materials, compositions, and/or dosage forms which are, within the scope of sound medical judgment, suitable for use in contact with the tissues of human beings and animals without excessive toxicity, irritation, allergic response, or other problem or complication, commensurate with a reasonable benefit/risk ratio.

Examples of pharmaceutically acceptable carriers include: (1) sugars, such as lactose, glucose and sucrose; (2) starches, such as corn starch and potato starch; (3) cellulose, and its derivatives, such as sodium carboxymethyl cellulose, ethyl cellulose and cellulose acetate; (4) powdered tragacanth; (5) malt; (6) gelatin; (7) talc; (8) excipients, such as cocoa butter and suppository waxes; (9) oils, such as peanut oil, cottonseed oil, safflower oil, sesame oil, olive oil, corn oil and soybean oil; (10) glycols, such as propylene glycol; (11) polyols, such as glycerin, sorbitol, mannitol and polyethylene glycol; (12) esters, such as ethyl oleate and ethyl laurate; (13) agar; (14) buffering agents, such as magnesium hydroxide and aluminum hydroxide; (15) alginic acid; (16) pyrogen-free water; (17) isotonic saline; (18) Ringer's solution; (19) ethyl alcohol; (20) phosphate buffer solutions; (21) cyclodextrins such as Captisol®; and (22) other non-toxic compatible substances employed in pharmaceutical formulations.

Examples of pharmaceutically acceptable antioxidants include: (1) water soluble antioxidants, such as ascorbic acid, cysteine hydrochloride, sodium bisulfate, sodium metabisulfite, sodium sulfite and the like; (2) oil-soluble antioxidants, such as ascorbyl palmitate, butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), lecithin, propyl gallate, alpha-tocopherol, and the like; and (3) metal chelating agents, such as citric acid, ethylenediamine tetraacetic acid (EDTA), sorbitol, tartaric acid, phosphoric acid, and the like. Solid dosage forms (e.g., capsules, tablets, pills, dragees, powders, granules and the like) can include one or more pharmaceutically acceptable carriers, such as sodium citrate or dicalcium phosphate, and/or any of the following: (1) fillers or extenders, such as starches, lactose, sucrose, glucose, mannitol, and/or silicic acid; (2) binders, such as, for example, carboxymethylcellulose, alginates, gelatin, polyvinyl pyrrolidone, sucrose and/or acacia; (3) humectants, such as glycerol; (4) disintegrating agents, such as agar-agar, calcium carbonate, potato or tapioca starch, alginic acid, certain silicates, and sodium carbonate; (5) solution retarding agents, such as paraffin; (6) absorption accelerators, such as quaternary ammonium compounds; (7) wetting agents, such as, for example, cetyl alcohol and glycerol monostearate; (8) absorbents, such as kaolin and bentonite clay; (9) lubricants, such a talc, calcium stearate, magnesium stearate, solid polyethylene glycols, sodium lauryl sulfate, and mixtures thereof; and (10) coloring agents. Liquid dosage forms can include pharmaceutically acceptable emulsions, microemulsions, solutions, suspensions, syrups and elixirs. In addition to the active ingredient, the liquid dosage forms may contain inert diluents commonly used in the art, such as, for example, water or other solvents, solubilizing agents and emulsifiers, such as ethyl alcohol, isopropyl alcohol, ethyl carbonate, ethyl acetate, benzyl alcohol, benzyl benzoate, propylene glycol, 1 ,3-butylene glycol, oils (in particular, cottonseed, groundnut, corn, germ, olive, castor and sesame oils), glycerol, tetrahydrofuryl alcohol, polyethylene glycols and fatty acid esters of sorbitan, and mixtures thereof.

Suspensions, in addition to the active compounds, may contain suspending agents as, for example, ethoxylated isostearyl alcohols, polyoxyethylene sorbitol and sorbitan esters, microcrystalline cellulose, aluminum metahydroxide, bentonite, agar-agar and tragacanth, and mixtures thereof.

Ointments, pastes, creams and gels may contain, in addition to an active compound, excipients, such as animal and vegetable fats, oils, waxes, paraffins, starch, tragacanth, cellulose derivatives, polyethylene glycols, silicones, bentonites, silicic acid, talc and zinc oxide, or mixtures thereof.

Powders and sprays can contain, in addition to an active compound, excipients such as lactose, talc, silicic acid, aluminum hydroxide, calcium silicates and polyamide powder, or mixtures of these substances. Sprays can additionally contain customary propellants, such as chlorofluorohydrocarbons and volatile unsubstituted hydrocarbons, such as butane and propane.

The formulations may conveniently be presented in unit dosage form and may be prepared by any methods well known in the art of pharmacy. The amount of active ingredient which can be combined with a carrier material to produce a single dosage form will vary depending upon the host being treated, the particular mode of administration. The amount of active ingredient that can be combined with a carrier material to produce a single dosage form will generally be that amount of the compound which produces a therapeutic effect. Generally, out of one hundred per cent, this amount will range from about 1 per cent to about ninety-nine percent of active ingredient, preferably from about 5 per cent to about 70 per cent, most preferably from about 10 per cent to about 30 per cent. The tablets, and other solid dosage forms of the pharmaceutical compositions disclosed herein, such as dragees, capsules, pills and granules, may optionally be scored or prepared with coatings and shells, such as enteric coatings and other coatings well known in the pharmaceutical-formulating art. They may also be formulated so as to provide slow or controlled release of the active ingredient therein using, for example, hydroxypropylmethyl cellulose in varying proportions to provide the desired release profile, other polymer matrices, liposomes and/or microspheres. They may be sterilized by, for example, filtration through a bacteria- retaining filter, or by incorporating sterilizing agents in the form of sterile solid compositions that can be dissolved in sterile water, or some other sterile injectable medium immediately before use. These compositions may also optionally contain opacifying agents and may be of a composition that they release the active ingredient(s) only, or preferentially, in a certain portion of the gastrointestinal tract, optionally, in a delayed manner. Examples of embedding compositions that can be used include polymeric substances and waxes. The active ingredient can also be in micro-encapsulated form, if appropriate, with one or more of the above-described excipients.

Dosage forms for the topical or transdermal administration of a compound of this invention include powders, sprays, ointments, pastes, creams, lotions, gels, solutions, patches and inhalants. The active compound may be mixed under sterile conditions with a pharmaceutically acceptable carrier, and with any preservatives, buffers, or propellants that may be required.

The formulations disclosed herein can be delivered via a device. Exemplary devices include, but are not limited to, a catheter, wire, stent, or other intraluminal device. Further exemplary delivery devices also include a patch, bandage, mouthguard, or dental apparatus. Transdermal patches have the added advantage of providing controlled delivery of a compound disclosed herein to the body. Such dosage forms can be made by dissolving or dispersing the compound in the proper medium. Absorption enhancers can also be used to increase the flux of the compound across the skin. The rate of such flux can be controlled by either providing a rate controlling membrane or dispersing the compound in a polymer matrix or gel.

Ophthalmic formulations, eye ointments, drops, solutions and the like, are also contemplated as being within the scope of this invention.

In some cases, in order to prolong the effect of a drug, it is desirable to slow the absorption of the drug from subcutaneous or intramuscular injection. This may be accomplished by the use of a liquid suspension of crystalline or amorphous material having poor water solubility. The rate of absorption of the drug then depends upon its rate of dissolution, which, in turn, may depend upon crystal size and crystalline form. Alternatively, delayed absorption of a parenterally administered drug form is accomplished by dissolving or suspending the drug in an oil vehicle. Injectable depot forms are made by forming microencapsule matrices of the subject compounds in biodegradable polymers such as polylactide-polyglycolide. Depending on the ratio of drug to polymer, and the nature of the particular polymer employed, the rate of drug release can be controlled. Examples of other biodegradable polymers include poly(orthoesters) and poly(anhydrides). Depot injectable formulations are also prepared by entrapping the drug in liposomes or microemulsions that are compatible with body tissue.

When the compounds disclosed herein are administered as pharmaceuticals, to humans and animals, they can be given per se or as a pharmaceutical composition containing, for example, 0.1 to 99.5% (more preferably, 0.5 to 90%) of active ingredient in combination with a pharmaceutically acceptable carrier. The formulations can be administered topically, orally, transdermally, rectally, vaginally, parentally, intranasally, intrapulmonary, intraocularly, intravenously, intramuscularly, intraarterially, intrathecally, intracapsularly, intraorbitally, intracardiacly, intradermally, intraperitoneally, transtracheally, subcutaneously, subcuticularly, intraarticularly, subcapsularly, subarachnoidly, intraspinally, intrasternally or by inhalation. One specific embodiment is an antitussive composition for peroral administration comprising an agent that inhibits both a TRPAl -mediated current with an IC₅₀ of 1 micromolar or less, and an orally-acceptable pharmaceutical carrier in the form of an aqueous-based liquid, or solid dissolvable in the mouth, selected from the group consisting of syrup, elixer, suspension, spray, lozenge, chewable lozenge, powder, and chewable tablet. Such antitussive compositions can include one or more additional agents for treating cough, allergy or asthma symptom selected from the group consisting of: antihistamines, 5-lipoxygenase inhibitors, leukotriene inhibitors, H3 inhibitors, β-adrenergic receptor agonists, xanthine derivatives, α-adrenergic receptor agonists, mast cell stabilizers, expectorants, NKl, NK2 and NK3 tachykinin receptor antagonists, and GABA_B agonists. Still another embodiment is a metered dose aerosol dispenser containing an aerosol pharmaceutical composition for pulmonary or nasal delivery comprising an agent that inhibits a TRPAl -mediated current with an IC₅₀ of 1 micromolar or less. For instance, it can be a metered dose inhaler, a dry powder inhaler or an air-jet nebulizer.

Dosages Actual dosage levels of the active ingredients in the pharmaceutical compositions of this invention may be varied so as to obtain an amount of the active ingredient that is effective to achieve the desired therapeutic response for a particular patient, composition, and mode of administration, without being toxic to the patient.

The selected dosage level will depend upon a variety of factors including the activity of the particular compound disclosed herein employed, or the ester, salt or amide thereof, the route of administration, the time of administration, the rate of excretion of the particular compound being employed, the duration of the treatment, other drugs, compounds and/or materials used in combination with the particular compound employed, the age, sex, weight, condition, general health and prior medical history of the patient being treated, and like factors well known in the medical arts.

A physician or veterinarian having ordinary skill in the art can readily determine and prescribe the effective amount of the pharmaceutical composition required. For example, the physician or veterinarian could start doses of the compounds of the invention employed in the pharmaceutical composition at levels lower than that required in order to achieve the desired therapeutic effect and gradually increase the dosage until the desired effect is achieved.

In general, a suitable daily dose of a compound of the invention will be that amount of the compound that is the lowest dose effective to produce a therapeutic effect. Such an effective dose will generally depend upon the factors described above. Generally, intravenous, intracerebroventricular and subcutaneous doses of the compounds of this invention for a patient will range from about 0.0001 to about 100 mg per kilogram of body weight per day. For example, the dose can be 1-50, 1-25, or 5-10 mg/kg.

If desired, the effective daily dose of the active compound may be administered as two, three, four, five, six or more sub-doses administered separately at appropriate intervals throughout the day, optionally, in unit dosage forms.

Disease and Injury Models Compounds that antagonize TRPAl function may be useful in the prophylaxis and treatment of any of the foregoing injuries, diseases, disorders, or conditions. In addition to in vitro assays of the activity of these compounds, their efficacy can be readily tested in one or more animal models. There are numerous animal models for studying pain. The various models use various agents or procedures to simulate pain resulting from injuries, diseases, or other conditions. Blackburn-Munro (2004) Trends in Pharmacological Sciences 25: 299-305 (see, for example, Tables 1, 3, or 4). Behavioral characteristics of challenged animals can then be observed. Compounds or procedures that may reduce pain in the animals can be readily tested by observing behavioral characteristics of challenged animals in the presence versus the absence of the test compound(s) or procedure.

Exemplary behavioral tests used to study chronic pain include tests of spontaneous pain, allodynia, and hyperalgesia. Id. To assess spontaneous pain, posture, gait, nocifensive signs (e.g., paw licking, excessive grooming, excessive exploratory behavior, guarding of the injured body part, and self -mutilation) can be observed. To measure evoked pain, behavioral responses can be examined following exposure to heat (e.g., thermal injury model).

Exemplary animal models of pain include, but are not limited to, the Chung model, the carageenan induced hyperalgesia model, the Freund's complete adjuvant induced hyperalgesia model, the thermal injury model, the formalin model and the Bennett Model. The Chung model of neuropathic pain (without inflammation) involves ligating one or more spinal nerves. Chung et al. (2004) Methods MoI Med 99: 35-45; Kim and Chung (1992) Pain 50: 355-363. Ligation of the spinal nerves results in a variety of behavioral changes in the animals including heat hyperalgesia, cold allodynia, and ongoing pain. Compounds that antagonize TRPAI can be administered to ligated animals to assess whether they diminish these ligation-induced behavioral changes in comparison to that observed in the absence of compound. Carageenan induced hyperalgesia and Freund's complete adjuvant (FCA) induced hyperalgesia are models of inflammatory pain. Walker et al. (2003) Journal of Pharmacol Exp Ther 304: 56-62; McGaraughty et al. (2003) Br J Pharmacol 140: 1381-1388; Honore et al. (2005) J Pharmacol Exp Ther. Compounds that antagonize TRPAl can be administered to carrageenan or FCA challenged animals to assess whether they diminish thermal hyperalgesia in comparison to that observed in the absence of compound, hi addition, the ability of compounds that antagonize TRPAl function to diminish cold and/or mechanical hypersensitivity can also be assessed in these models. Typically, the carrageenan induced hyperalgesia model is believed to mimic acute inflammatory pain and the CFA model is believed to mimic chronic pain and chronic inflammatory pain.

Exemplary models of inflammatory pain include the rat model of intraplantar bradykinin injection. Briefly, the baseline thermal sensitivity of the animals is assessed on a Hargreave's apparatus. TRPAl blockers are then administered systemically. Bradykinin is subsequently injected into the paw and a hyperalgesia is allowed to develop. Thermal escape latency is then measured at multiple time points over the next few hours (Chuang et al., 2001 ; Vale et al., 2004). Inflammation is often an important contributing factor to pain. As such, it is useful to identify compounds that act as anti-inflammatories. Many compounds that reduce neural activity also prevent neurogenic inflammation. To measure inflammation directly, the volume of a rat paw can be assessed using a plethysmometer. After baseline measurement is taken, carrageenan can be injected into the paw and the volume can be monitored over the course of hours in animals that have been treated with vehicle or drug. Drugs that reduce the paw swelling are considered to be anti-inflammatory.

Migraines are associated with significant pain and inability to complete normal tasks. Several models of migraine exist including the rat neurogenic inflammation model, (see Buzzi et al (1990) Br J Pharmacol; 99:202-206), and the Burstein Model (see Strassman et al., (1996) Nature 384: 560-564). The Bennett model uses prolonged ischemia of the paw to mirror chronic pain. Xanthos et al. (2004) J Pain 5: Sl . This provides an animal model for chronic pain including postoperative pain, complex regional pain syndrome, and reflex sympathetic dystrophy. Prolonged ischemia induces behavioral changes in the animals including hyperalgesia to mechanical stimuli, sensitivity to cold, pain behaviors (e.g., paw shaking, licking, and/or favoring), and hyperpathia. Compounds that antagonize TRPAl can be administered to challenged animals to assess whether they diminish any or all of these behaviors in comparison to that observed in the absence of compound. Similar experiments can be conducted in a thermal injury or UV-burn model which can be used to mimic post-operative pain.

Additional models of neuropathic pain include central pain models based on spinal cord injury. Chronic pain is generated by inducing a spinal cord injury, for example, by dropping a weight on a surgically exposed area of spinal cord (e.g., weight-drop model). Spinal cord injury can additionally be induced by crushing or compressing the spinal cord, by delivering neurotoxin, using photochemicals, or by hemisecting the spinal cord. Wang and Wang (2003).

Additional models of neuropathic pain include peripheral nerve injury models. Exemplary models include, but are not limited to, the neuroma model, the Bennett model, the Seltzer model, the Chung model (ligation at either L5 or L5/L6), the sciatic cryoneurolysis model, the inferior caudal trunk resection model, and the sciatic inflammatory neuritis model. Id.

Exemplary models of neuropathic pain associated with particular diseases are also available. Diabetes and shingles are two diseases often accompanied by neuropathic pain. Even following an acute shingles episodes, some patients continue to suffer from postherpetic neuralgia and experience persistent pain lasting years. Neuropathic pain caused by shingles and/or postherpetic neuralgia can be studied in the postherpetic neuralgia model (PHN). Diabetic neuropathy can be studied in diabetic mouse models, as well as chemically induced models of diabetic neuropathy. Wang and Wang (2003). As outlined above, cancer pain may have any of a number of causes, and numerous animal models exist to examine cancer pain related to, for example, chemotherapeutics or tumor infiltration. Exemplary models of toxin-related cancer pain include the vincristine-induced peripheral neuropathy model, the taxol-induced peripheral neuropathy model, and the cisplatin- induced peripheral neuropathy model. Wang and Wang (2003). An exemplary model of cancer pain caused by tumor infiltration is the cancer invasion pain model (CIP). Id.

Primary and metastatic bone cancers are associated with tremendous pain. Several models of bone cancer pain exist including the mouse femur bone cancer pain model (FBC), the mouse calcaneus bone cancer pain model (CBC), and the rat tibia bone cancer model (TBC). Id. An additional model of pain is the formalin model. Like the carrageenan and CFA models, the formalin model involves injection of an irritant intradermally or intraperitoneally into an animal. Injection of formalin, a 37 percent solution of formaldehyde, is the most commonly used agent for intradermal paw injection (the formalin test). Injection of a 0.5 to 15 percent solution of formalin (usually about 3.5%) into the dorsal or plantar surface of the fore- or hindpaw produces a biphasic painful response of increasing and decreasing intensity for about 60 minutes after the injection. Typical responses include the paw being lifted, licked, nibbled, or shaken. These responses are considered nociceptive. The initial phase of the response (also known as the Early Phase), which lasts 3 to 5 minutes, is probably due to direct chemical stimulation of nociceptors. This is followed by 10 to 15 minutes during which animals display little behavior suggestive of nociception. The second phase of this response (also known as the Late Phase) starts about 15 to 20 minutes after the formalin injection and lasts 20 to 40 minutes, initially rising with both number and frequency of nociceptive behaviors, reaching a peak, then falling off. The intensities of these nociceptive behaviors are dependent on the concentration of formalin used. The second phase involves a period of sensitization during which inflammatory phenomena occur. The two phases of responsiveness to formalin injection makes the formalin model an appropriate model for studying mociceptive and acute inflammatory pain. It may also model, in some respects, neuropathic pain.

In addition to any of the foregoing models of chronic pain, compounds that antagonize TRPAl function can be tested in one or more models of acute pain. Valenzano et al. (2005) Neuropharmacology 48: 658-672. Regardless of whether compounds are tested in models of chronic pain, acute pain, or both, these studies are typically (though not exclusively) conducted, for example, in mice, rats, or guinea pigs. Additionally, compounds can be tested in various cell lines that provide in vitro assays of pain. Wang and Wang (2003).

Many individuals seeking treatment for pain suffer from visceral pain. Animal models of visceral pain include the rat model of inflammatory uterine pain (Wesselmann et al., (1997) Pain 73:309-317), injection of mustard oil into the gastrointestinal tract to mimic irritable bowel syndrome (Kimball et al., (2005) Am J Physiol Gastrointest Liver Physiol, 288(6):G 1266-73). injection of mustard oil into the bladder to mimic overactive bladder or bladder cystitis (Riazimand (2004), BJU 94: 158-163). The effectiveness of a TRPAl compound can be assessed by a decrease in writhing, gastrointestinal inflammation or bladder excitability.

For testing the efficacy of TRPAl antagonists for the treatment of cough, experiments using the conscious guinea pig model of cough can be readily conducted. Tanaka and Maruyama (2003) Journal Pharmacol Sci 93: 465-470; McLeod et al. (2001) Br J Pharmacol 132: 1175- 1178. Briefly, guinea pigs serve as a useful animal model for cough because, unlike other rodents such as mice and rats, guinea pigs actually cough. Furthermore, guinea pig coughing appears to mimic human coughing in terms of the posture, behavior, and appearance of the coughing animal. To induce cough, conscious guinea pigs are exposed to an inducing agent such as citric acid or capsaicin. The response of the animal is measured by counting the number of coughs.

The effectiveness of a cough suppressing agent, for example a compound that inhibits TRPAl , can be measured by administering the agent and assessing the ability of the agent to decrease the number of coughs elicited by exposure to citric acid, capsaicin, or other similar cough-inducing agent. In this way, TRPAl inhibitors for use in the treatment of cough can be readily evaluated and identified.

Additional models of cough include the unconscious guinea pig model. Rouget et al.

(2004) Br J Pharmacol 141 : 1077-1083. Either of the foregoing models can be adapted for use with other animals capable of coughing. Exemplary additional animals capable of coughing include cats and dogs.

Numerous rodent models of incontinence exist. These include models of incontinence induced by nerve damage, urethral impingement and inflammation. Models of urethral impingement include the rat bladder outflow obstruction model. (Pandita, RK, and Andersson KE. Effects of intravesical administration of the K+ channel opener, Z.D6169, in conscious rats with and without bladder outflow obstruction. J Urol 162: 943-948, 1999). Inflammatory models include injection of mustard oil into the bladder.

To test the effectiveness of a TRPAl inhibitor compound in treating incontinence, varying concentrations of compound (e.g., low, medium, and high concentration) can be administered to rats following surgical partial bladder outlet obstruction (BOO). Efficacy of the varying doses of TRPAl inhibitory compound can be compared to controls administered excipients alone (sham control). Efficacy can further be compared to rats administered a positive control, such as atropine. Atropine is expected to decrease bladder over-activity following partial bladder outlet obstruction in the BOO model. Note that when testing compounds in the BOO model, compounds can be administered directly to the bladder or urethra (e.g., by catheter) or compounds can be administered systemically (e.g., orally, intraveneously, intraperitoneally, etc).

Several rat models of pancreatitic pain have recently been described (Lu, 2003,

Anesthesiology 98(3): 734-740; Winston et al., 2003, Journal of Pain 4(6): 329-337). Lu et al. induced pancreatitis by systemic delivery of dibutylin dichloride in rats. Rats showed an increase in withdrawal events after von Frey filament stimulation of the abdomen and decreased withdrawal latency after thermal stimulation during a period of 7 days. The pain state induced in these animals was also characterized by increased levels of substance P in spinal cords (Lu, et al., 2003). To test the efficacy of a TRPAl inhibitor in this model, a TRPAl inhibitor can be administered following or concurrently with delivery of dibutylin dichloride. Control animals can be administered a carrier or a known pain reliever. Indicia of pain can be measured.

Efficacy of a TRPAl inhibitor can be evaluated by comparing the indicia of pain observed in animals receiving a TRPAl inhibitor to that of animals that did not receive a TRPAl inhibitor. Additionally, efficacy of a TRPAl inhibitor can be compared to that of known pain medicaments. The efficacy of von Frey filament testing as a means to measure nociceptive behavior was also shown by inducing pancreatitis by systemic L-arginine administration (Winston et al, 2003). The efficacy of a TRPAl inhibitor can similarly be tested following pancreatitis induced by systemic L-arginine administration.

Lu et al. also described direct behavioral assays for pancreatic pain using acute noxious stimulation of the pancreas via an indwelling ductal canula in awake and freely moving rats. These assays included cage crossing, rearing, and hind limb extension in response to intrapancreatic bradykinin infusion. Intrathecal administration of either D-APV (NMDA receptor antagonist) or morphine alone partially reduced visceral pain behaviors in this model. Combinations of both reduced pain behaviors to baseline. The efficacy of a TRPAl inhibitor can similarly be tested in this system.

Any of the foregoing animal models may be used to evaluate the efficacy of a TRPAl inhibitor in treating pain associated with pancreatitis. The efficacy can be compared to a no teatment or placebo control. Additionally or alternatively, efficacy can be evaluated in comparison to one or more known pain relieving medicaments. The following examples are meant to be illustrative and are not meant to be limiting in any way.

Examples

Example 1 : High Thoughput Screening Assay The assay depended on detection of the rise in intracellular Ca²⁺ concentration ([Ca²⁺],) following channel activation in cells inducibly expressing the TRPAl channel. Ca²⁺ rise was quantified with the use of fluorescent Ca²⁺ indicators that were loaded into cells and thereafter indicated the [Ca²⁺],. Ca²⁺ influx followed activation of the TRPAl channel. Compounds inhibiting the [Ca²⁺], rise were considered hits for further investigation.

The commercially available HEK293/TREx line (Invitrogen) was stably transfected with a TRPAl construct (specifically a construct encoding a TRPAl protein with an amino acid sequence depicted in SEQ ID NO: 1) and screened by conventional calcium imaging to find clones with TRPAl expression following stimulation with 1 μg/ml tetracycline. These cells were maintained in the growth medium recommended by the manufacturer supplemented with 100 μg/ml hygromycin to promote retention of the TRPAl construct. After growing to near confluency, cells were plated at a density of -25,000 cells/well in 384 well CellBind plates

(Corning) in the presence of 1 μg/ml tetracycline, and allowed to grow for 20-30 hrs. A nearly confluent monolayer resulted. Cells were then loaded with Ca²⁺ dye: Fura-2/AM or Fluo4/AM was added to the wells to a final concentration of 2 μM or 1 μM, respectively, and incubated for 80 min or 60 min, respectively, at room temperature. Supernatant was then removed from the cells by inverting plates with a sharp flick, and 40 μl Hank's Balanced Salt Solution (HBSS; 0.185 g/1 D-glucose, 0.9767 g/1 MgSO₄ (anhydrous), 0.4 g/1 KCl, 0.06 g/1 KH₂PO₄ (anhydrous), 0.35 g/1 NaHCO₃, 8.0 g/1 NaCl, and 0.04788 g/1 Na₂HPO₄ (anhydrous); pH 7.4) was then added to each well. Following ~ 1 hour for recovery from loading, cells were assayed using the Hamamatsu FDSS 6000 system, which permitted illumination alternately at 340 nM and 380 nM for Fura-2 experiments, or at 485 nM for Fluo4 experiments. Frames were acquired at a rate of 0.2 Hz. During the assay, the plates were continuously vortexed, with pipette mixing of wells following addition of each reagent. For the screening assay, 13 μl of a diluted stock (at 50 μM) was added to each well for 2 minutes following the collection of a short (4 frame) baseline. 13 μl 37.5 μM AITC (allylisothiocyanate) was then added to each well, achieving a final concentration of 10 μM each compound and 7.5 μM AITC. Data was collected for ~3 minutes following addition of AITC, where the fluorescent intensity (for Fluo4) and the F340/F380 ratio (for Fura-2) were proportional to the [Ca²⁺],. Negative controls consisted of HEK293/TREx TRPAl cells exposed to AITC, but no compound. Positive control cells were usually HEK293/TREx ("parental") cells exposed to AITC but no compound, but sometimes normal HEK/293 TREx TRPAl cells were also used, but not exposed to AITC or compound. These controls defined a screening window, and "hits" were defined as those compounds inhibiting the fluorescence response by at least 40%. IC50 values were determined for compounds defined as "hits." The Fluo4 cell-based fluorescence assay was used to determine the intracellular Ca²⁺ concentration in the presence of varying drug concentration. Concentrations tested were 40 μM, 20 μM, 10 μM, 5 μM, 2.5 μM, 1.25 μM, and 0.625 μM. Compounds were tested in triplicate at all concentrations. Standard software was used to fit IC₅₀ curves.

Additionally or alternatively, efficacy can be represented as % inhibition in the presence (of a given concentration of compound) versus the absence of compound or in comparison to a control compound. For example, efficacy can be represented as % inhibition of ion flux in the presence versus the absence of compound.

Example 2: Patch clamp experiments

Patch clamp experiments permit the detection of currents through the TRPAl channel in the cell line described above. To permit recording of current at a stable level and prevent the "rundown" observed by other labs, it is necessary to use the perforated patch technique, which prevents dialysis of the cytoplasm with the pipette solution. In normal whole-cell patch clamp recordings, a glass electrode is brought into contact with a single cell and a high-resistance (gigaohm) seal is established with the cell membrane. The membrane is then ruptured to achieve the whole-cell configuration, permitting control of the voltage of the cell membrane and measurement of currents flowing across the membrane using the amplifier attached to the electrode and resulting in the replacement of cytoplasm with the pipette solution. In contrast, in the perforated patch mode, an antibiotic, amphotericin, is present in the pipette solution and diffuses into contact with the cell after the seal is achieved, over the course of several minutes. The amphotericin forms ion-permeable pores in the membrane under the pipette, permitting passage of some ions but maintaining most native cytosolic components. A perfusion system permits control of the extracellular solution, including the addition of blockers and activators of the current. The current can be activated by addition of 5 μM AITC to the solution.

TRPAl cells were induced 20-48 hours, removed from growth plates, and replated at low density (to attain good single-cell physical separation) on glass coverslips for measurement. In some cases, cells were grown in low density overnight on glass coverslips. Patch clamp recordings were made in the whole-cell mode with a holding potential of -40 mV. Every 5 seconds, a voltage ramp was applied from -120 to +100 mV, 400 ms in duration. Currents elicited were quantified at -80 mV and +80 mV. The internal solution consisted of 140 mM cesium aspartate, 10 mM EGTA, 2.2 mM CaCl₂, 2.08 mM MgCl₂ and 10 mM HEPES, pH 7.2, with 50 nM calculated free Ca²⁺ and 60 mg/ml amphotericin added immediately prior to experiments. The external solution consisted of 150 mM NaCl, 4.5 mM KCl, 3 mM MgCl₂, 10 mM HEPES, 10 mM glutamine, ImM EGTA, pH 7.4. Upon addition of AITC, TRPAl current was induced only in TRPAl -expressing cells and not in parental HEK293 TREx cells. Removal of the AITC stimulus causes most of the current to go away. Potential blockers were tested for ability to block both inward and outward currents in the continued presence of AITC.

IC_5O of compounds was estimated by testing each compound at 5 μM and 500 nM. When 5 μM compound showed no block, IC50 was estimated as > 10 μM. When 5 μM compound showed 50% or less block, a rough estimate of IC50 in the range of 5-10 μM could be made. IC₅₀ for compounds between 500 nM and 5 μM was similarly estimated. Compounds blocking 50% or more at 500 nM are retested at multiple concentrations, and the % block at each is fitted by standard equations to determine IC5₀ accurately using a 5-6 point concentration/response experiment.

Example 3. Other Screening Assays

Although the exemplary TRPAl inhibitors provided herein were identified using the assays described in Examples 1 and 2, other cell-based assays can be used to identify and/or characterize TRPAl inhibitors. One such assay is described in US Application Serial No.

11/078, 188, filed March 11 , 2005, the contents of which are hereby incorporated by reference in their entirety. TRPAl protein can be expressed in the prokaryotic cell system described in Application Serial No. 11/078,188, and this system can be used to screen for compounds that modulate an activity of the TRPAl protein. Alternatively, an ion channel other than TRPAl can be expressed in the prokaryotic cell system, and the system can be used to evaluate the activity profile of identified TRPAl inhibitors with respect to other ion channels.

Any assays performed to identify and/or characterize compounds that inhibit an activity of TRPAl can be performed in a high-throughput fashion, or can be performed on a smaller scale examining individual compounds or small numbers of compounds. Additionally, any of these assays can be performed (i) as a primary assay to identify compounds that inhibit a function of TRPAl ; (ii) as a secondary assay to assess the specificity of a compound with respect to its activity against other ion channels; (iii) as an assay used in a medicinal chemistry program to optimize subject compounds.

Example 4: Testing of TRPAl Antagonists in a Thermal Injury Model of Pain The thermal injury model can be used to evaluate the effectiveness of an exemplary

TRPAl inhibitor in the treatment of nociceptive pain.

Briefly, the following protocol may be used. Male Holtzman rats (approximately 300 grams) are tested on thermal escape using a Hargreaves type apparatus. Under light anesthesia, a thermal injury (52 ⁰C for 45 seconds) is applied to one heel. The animals are tested for thermal escape latency of the injured and uninjured paw before and at 30, 60, 80, and 120 minutes after injury. Drug (a TRPAl inhibitor) or vehicle (0.5% methylcellulose) is administered after the baseline measurement and approximately 15-20 minutes prior to the thermal injury. In addition to the escape latency measurement, behavioral observations are made throughout the experiment.

Example 5: Testing of TRPAl Antagonists in the Chung Model Of Neuropathic Pain

Briefly, male Sprague Dawley rats (approximately 175 grams) are prepared with ligation of the L4/5 nerve roots. After 5-8 days, the animals are tested for tactile allodynia using Von Frey hairs. Thresholds are assessed with the "up-down" method. Drug or vehicle is administered and the animals tested periodically over the next four hours.

General Procedure A for the Preparation of Amides by Coupling Using EDCI To a mixture of theophylline-7 -acetic acid (2 mmol), DMAP (2 mmol), substituted phenethylamine (2 mmol) and DIPEA (4 mmol) in DMF (20 mL) was added EDCI (2 mmol). The reaction mixture was heated to 40⁰C and stirred over night. The solution was concentrated in vacuo and the residue was dissolved in EtOAc (100 mL), washed with H₂O, citric acid (10%), NaHCO₃ (sat.) and brine, dried over Na₂SO₄ and concentrated in vacuo. The crude product was purified by flash chromatography on silica gel eluting with MeOH/EtOAc (1-8%).

General Procedure B for the Preparation of Amides Via Acid Chloride A suspension of theophylline-7-acetic acid (2 mmol) in CHCl₃ (15 mL) and MeCN (15 mL) was cooled in an ice-water bath. Oxalyl chloride (2.2 mmol) was then added dropwise. Catalytic DMF (-25 μL) was then added. The mixture was stirred at room temperature over night. The solution was then cooled in an ice-water bath, and DMAP (2.5 mmol) was added in one portion. The substituted phenethylamine was added dropwise and the reaction mixture was stirred at room temperature over night. After diluting with CHCI₃ (50 mL), the mixture was washed with H₂O, citric acid (10% in H₂O), NaHCO₃ (sat.), dried over Na₂SO₄ and concentrated in vacuo. The crude product was purified by flash chromatography on silica gel eluting with MeOH/EtOAc (l~8%).

Preparation of Formula (II) Compound: Scheme 1

. NUHΛLI j ™^aπ/lvlel

1

2-(5-methyl-4-oxo-4,5-dihydro-3H-imidazo[4,5-c]pyridin-3- yl)acetic acid

Pyridine-3,4-diamine 1 can react with triethoxymethane to give imidazole pyridine 2, which subsequently can be oxidized and treated with an anhydride to afford imidazo pyridine-4- one 3. Compound 3 can be protected with a Boc group and alkylated. Removal of the Boc group with TFA, followed by an alkylation reaction yield ester 7. Ester 7 can be hydrolyzed and then coupled with p-tolylethanamine to give compound 10.

Preparation of Formula (III) Compound: Scheme 2

Step 5 NaH/Mel DMF

Treatment of pyridine-3,4-diamine 11 with triethoxymethane gives imidazole pyridine 12, which subsequently can be oxidized with MCPBA and treated with an anhydride to afford imidazo pyridine-4-one 13. Compound 13 can be sequentially alkylated with ClCHaCC^Et and MeI to yield ester 17. Ester 17 can be hydrolyzed under a basic condition and then coupled with p-tolylethanamine to give compound 15.

Preparation of Formula (IV) Compound: Scheme 3

Stepi Step 3 Step 4

18

C₆H₈N₂O₂ 19 20 21 22

MoI. Wt.: C₆H₈N₂O₃ C₇H₇CIN₂O₃ C₇H₈N₄O₂ C₁₁H₁₄N₄O₄

140.14 MoI. WL: 156.14 MoI. Wt.: 202.59 MoI. Wt.: 180.16 MoI. Wt: 266.25

Pyrimidine-2,4-dione 18 can be transformed to dihydropyrimidine-2,4,5-trione 19. Formylation of compound 19, followed by a reaction with hydrazine, can result in pyrazolopyrimidine-dione 21. Subsequently compound 21 can be alkylated by ethyl bromoacetate and hydrolyzed to afford carboxylic acid 23. Compound 23 can be coupled with 2- /j-tolylethanamine to give compound 24.

Preparation of Formula (V) Compound: Scheme 4

C₁₆H₁₆N₄O₄ C₂₅H₂₇N₅O₃ C₁₈H₂₁N₅O₃ MoI. Wt.. 328.32 Md. Wt.: 445.51 MoI. Wl.: 355.39 Treatment of l,3-dimethylpyrimidine-2,4,6(7H,3H5H)-trione (25) with POCl₃ can afford aldehyde 26, which can react with hydrazine to give 5,7-dimethyl-lΗ-pyrazolo[3,4- d]pyrimidine-4,6(5H,7H)-dione (27). Compound 27 can be protected by BnCl and then alkylated to yield ester 29. Ester 29 can be hydrolyzed with NaOH/H₂O, followed by coupling with amine 31 to afford compound 32. Hydrolysis of compound 32 leads to compound 33.

Intermediate ester 29 can also be prepared by an Reformatsky Reaction of compound 26, followed by reacting with hydrazine, as shown in Scheme 5. Scheme 5

29

C₁₁H₁₄N₄O₄ MoI. Wt.: 266.25

Preparation of Formula (VI) Compound Scheme 6

126.16

45 46

C₉H₁₁N₃O₃ C₁₈H₂₂N₄O₂ MoI. Wt.: 209.20 MoI. Wt.: 32639

Reacting methylamine with cyanic bromide, followed by a N-alkylaton reaction gives cyanamide 39. Compound 39 can be converted to 5-amino-l,2-dimethyl-lH-pyrrol-3(2H)-one (40). Treatment of compound 40 with a bromination reagent and then an amination reagent leads to the formation of 4,5-diamino-l,2-dimethyl-lH-pyrrol-3(2H)-one (42), which can be transformed to 4,5-dimethyl-4,5-dihydropyrrolo[3,2-d]imidazol-6(lH)-one (43). Compound 43 can subsequently be alkylated with ethyl bromoacetate and hydrolyzed under a basic condition to afford carboxylic acid 45, which can be coupled with an amine to give compound 46.

Incorporation by Reference

All publications and patents mentioned herein, are hereby incorporated by reference in their entirety as if each individual publication or patent was specifically and individually indicated to be incorporated by reference.

Equivalents

Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, many equivalents to the specific embodiments of the invention described herein. Such equivalents are intended to be encompassed by the following claims.

Claims

We claim:

1. A method of treating a TRPAl mediated disorder, the method comprising administering to a subject a compound of formula (II),

Formula (II) wherein,

R¹ is Ci-C₆ alkyl, C₂-C₆ alkenyl, or C₂-C₆ alkynyl, each of which is optionally substituted with 1-

4 R⁵;

X is N or CR² R² is H, Q-C₆ alkyl, C₂-C₆ alkenyl, or C₂-C₆ alkynyl, each of which is optionally substituted with 1-4 R^5';

S(O), S(O)₂, NR₆, CH₂, cyclyl, aryl, heterocyclyl, or heteroaryl;

R³ is cyclyl, heterocyclyl, aryl, heteroaryl, each of which is optionally substituted with 1-4 R⁷; each R⁵ is independently halo, hydroxyl, alkoxy, amino, alkylamino, dialkylamino, cyano, nitro, amido, alkylamido, dialkylamido, thioyl, sulfonyl, cyclyl, heterocyclyl, aryl, or heteroaryl; each R⁶ is independently H, C]-C₆ alkyl, or arylalkyl; each R⁷ is independently C]-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, cyclyl, heterocyclyl, aryl, heteroaryl, halo, hydroxyl, alkoxy, aryloxy, arylalkoxy, amino, akylamino, dialkylamino, thioyl, alkylthioyl, sulfonyl, sulfonamidyl, amido, urea, sulfonylurea, hydroxy] alkoxyl, alkoxy alkoxyl, acyl, nitro, cyano, each of which is optionally substituted with 1-3 R⁸; each R⁸ is independently Cj-C₆ alkyl, C₂-C₆ alkenyl, or C₂-C₆ alkynyl, halo, hydroxyl, alkoxy, aryloxy, amino, akylamino, dialkylamino, thioyl, sulfonyl, sulfonamidyl, amido, urea, sulfonylurea acyl, nitro, cyano, cyclyl, heterocyclyl, aryl, or heteroaryl; each m and n are independently O, 1 , 2, 3, 4, 5, or 6, wherein m is at least 2 when L is connected to the methylene carbon via a heteroatom, each R⁹ is independently H, CpC₆ alkyl, C₂-C_O alkenyl, or C₂-C₆ alkynyl, halo, hydroxyl, alkoxy, aryloxy, arylalkoxy, amino, akylamino, dialkylamino, thioyl, alkylthioyl, sulfonyl, sulfonamidyl, amido, urea, sulfonylurea, acyl, nitro, cyano, each of which is optionally substituted with 1-3 R⁸.

2. The method of claim 1 , wherein X is CR².

3. The method of claim 1 , wherein X is N.

4. The method of claim 1, wherein R¹ is Ci_-6 alkyl.

5. The method of claim 1 , wherein R³ is monocyclic.

6. The method of claim 1 , wherein the compound is administered orally.

7. The method of claim 1 , wherein the TRPA 1 mediated disorder is pain.

8. The method of claim 1 , wherein the subject is a human.

9. A method of treating a TRPAl mediated disorder, the method comprising administering to a subject a compound of formula (III),

Formula (III) wherein, R¹ is Ci-C₆ alkyl, C₂-C₆ alkenyl, or C₂-C₆ alkynyl, each of which is optionally substituted with 1- 4 R⁵; X is N or CR² R² is Ci-C₆ alkyl, C₂-C_O alkenyl, or C₂-C₆ alkynyl, each of which is optionally substituted with 1-

4 R^5';

L is NR⁶SO₂, SO₂NR⁶, OC(O)NR⁶, NR⁶C(O)O, NR⁶C(O)NR⁶, NR⁶C(O), C(O)NR⁶, O, C(O), S,

S(O), S(O)₂, NR₅, CH₂, cyclyl, aryl, heterocyclyl, or heteroaryl; R³ is cyclyl, heterocyclyl, aryl, heteroaryl, each of which is optionally substituted with 1-4 R⁷; each R⁵ is independently halo, hydroxyl, alkoxy, amino, alkylamino, dialkylamino, cyano, nitro, amido, alkylamido, dialkylamido, thioyl, sulfonyl, cyclyl, heterocyclyl, aryl, or heteroaryl; each R⁶ is independently H, Cj-C₆ alkyl, or arylalkyl; each R⁷ is independently Ci-C₆ alkyl, C₂-C₆ alkenyl, or C₂-C₆ alkynyl, halo, hydroxyl, alkoxy, aryl, heteroaryl, cyclyl, aryloxy, arylalkoxy, amino, akylamino, dialkylamino, thioyl, alkylthioyl, sulfonyl, sulfonamidyl, amido, hydroxyl alkoxyl, alkoxy alkoxy], urea, sulfonylurea, acyl, nitro, cyano, each of which is independently substituted with 1-3 R⁸; each R⁸ is independently Ci-C₆ alkyl, C₂-C₆ alkenyl, or C₂-C₆ alkynyl, halo, hydroxyl, alkoxy, aryloxy, amino, akylamino, dialkylamino, thioyl, sulfonyl, sulfonamidyl, amido, urea, sulfonylurea acyl, nitro, cyano, cyclyl, heterocyclyl, ary], or heteroaryl; each R⁹ is independently H, Cj-C₆ alkyl, C₂-C₆ alkenyl, or C₂-C₆ alkynyl, halo, hydroxyl, alkoxy, aryloxy, arylalkoxy, amino, akylamino, dialkylamino, thioyl, alkylthioyl, sulfonyl, sulfonamidyl, amido, urea, sulfonylurea, acyl, nitro, cyano, each of which is independently substituted with 1-3

R⁸; each m and n are independently O, 1 , 2, 3, 4, 5, or 6.

10. The method of claim 9, wherein X is CR².

1 1. The method of claim 9, wherein X is N.

12. The method of claim 9, wherein R¹ is Q-₆ alkyl.

13. The method of claim 9, wherein R³ is monocyclic.

14. The method of claim 9, wherein the compound is administered orally.

15. The method of claim 9, wherein the TRPAl mediated disorder is pain.

16. The method of claim 9, wherein the subject is a human.