HK1050194B - Fused pyrazolyl compounds - Google Patents

Description

Fused pyrazole compound

background

cGMP is an intracellular second messenger that plays a very important role in controlling the activities of various cells. It is obtained by conversion from Guanosine Triphosphate (GTP) by soluble adenylate cyclase (sGC) and subsequent disruption with Phosphodiesterases (PDEs). Therefore, increasing the content of cGMP can be achieved by increasing the activity of sGC or decreasing the activity of PDEs.

Platelet aggregation is responsible for the pathogenesis of various cardiovascular diseases, such as arteriosclerosis, myocardial infarction, unstable angina, thrombosis and hypertension. Since low intracellular levels of cGMP lead to increased platelet aggregation, increasing the levels of cGMP in platelets can provide a method of treating these diseases. It is also known that intracellular cGMP levels also have an effect on other physiological functions such as penile erection.

Or compounds that increase intracellular cGMP levels by activating sGC or inhibiting PDEs are of clinical interest for diseases associated with low intracellular cGMP levels. It has been found that certain pyrazole compounds activate sGC and are therefore potential cardiovascular agents.

Disclosure of Invention

One aspect of the present invention relates to novel fused pyrazole compounds of formula (I) below:

each of Ar1, Ar2, and Ar3 in the formula may be phenyl, thienyl, pyrrolyl, or furan, preferably substituted with halogen, alkyl, hydroxy, alkoxycarbonyl, thiocarbonyl, aminocarbonyl, hydroxycarbonyl, alkoxyalkyl, aminoalkyl, or thioalkyl; each of X and Y may be O, S or NH; m is 1, 2 or 3; n is 0, 1, 2, 3 or 4. The above term carries an "alkyl group" which is preceded by an "alk-" (e.g., alkoxyalkyl) or followed by an "-alkyl" (e.g., hydroxyalkyl) group, the alkyl group having from 1 to 6 carbon atoms. Among them, X is preferably O, Y is preferably O, and m is preferably 1.

Referring to formula (I), a sub-series of compounds of the invention are characterized in that in these compounds Ar2 is preferably phenyl or furan, or Ar3 is thienyl or phenyl.

When Ar2 is phenyl or furan, Ar1 may be phenyl, optionally substituted with halogen, C_1-6Alkyl, hydroxy, alkoxycarbonyl, thiocarbonyl, aminocarbonyl, hydroxycarbonyl, alkoxyalkyl, aminoalkyl or thioalkyl. When Ar2 is phenyl or furan, Ar3 is thienyl or phenyl, in which case Ar1 is phenyl, optionally substituted by halogen, C_1-6Alkyl, hydroxy, alkoxycarbonyl, thiocarbonyl, aminocarbonyl, hydroxycarbonyl, alkoxyalkyl, aminoalkyl or thioalkyl.

When Ar3 is thienyl or phenyl, Ar1 may be phenyl, optionally substituted by halogen, C_1-6Alkyl, hydroxy, alkoxycarbonyl, thiocarbonyl, aminocarbonyl, hydroxycarbonyl, alkoxyalkyl, aminoalkyl or thioalkyl. When Ar3 is thienyl or phenyl, Ar2 may be furan or phenyl, optionally substituted with halogen、C_1-6Alkyl, hydroxy, alkoxycarbonyl, thiocarbonyl, aminocarbonyl, hydroxycarbonyl, alkoxyalkyl, aminoalkyl or thioalkyl, in which case Ar1 may be phenyl, optionally substituted by halogen, C_1-6Alkyl, hydroxy, alkoxycarbonyl, thiocarbonyl, aminocarbonyl, hydroxycarbonyl, alkoxyalkyl, aminoalkyl or thioalkyl.

Another sub-series of compounds according to the invention is characterized in that Ar2 is phenyl or furan, optionally substituted by halogen, C_1-6Alkyl, hydroxy, alkoxycarbonyl, thiocarbonyl, aminocarbonyl, hydroxycarbonyl, alkoxyalkyl, aminoalkyl or thioalkyl. In this case, Ar3 may be thienyl or phenyl, in which case Ar1 may be phenyl optionally substituted by halogen, C_1-6Alkyl, hydroxy, alkoxycarbonyl, thiocarbonyl, aminocarbonyl, hydroxycarbonyl, alkoxyalkyl, aminoalkyl or thioalkyl.

A further sub-series of compounds according to the invention is characterized in that Ar3 is thienyl or phenyl. In this case, Ar1 is phenyl, optionally substituted by halogen, C_1-6Alkyl, hydroxy, alkoxycarbonyl, thiocarbonyl, aminocarbonyl, hydroxycarbonyl, alkoxyalkyl, aminoalkyl or thioalkyl; or Ar2 is furan or phenyl, optionally substituted by halogen, C_1-6Alkyl, hydroxy, alkoxycarbonyl, thiocarbonyl, aminocarbonyl, hydroxycarbonyl, alkoxyalkyl, aminoalkyl or thioalkyl, in which case Ar1 may be phenyl, optionally substituted by halogen, C_1-6Alkyl, hydroxy, alkoxycarbonyl, thiocarbonyl, aminocarbonyl, hydroxycarbonyl, alkoxyalkyl, aminoalkyl or thioalkyl.

Preferred compounds of the invention are those wherein Ar1 is phenyl and Ar2 is furan, which are attached to the pyrazole ring at its 2-C position and substituted at its 5-C position with a methoxymethyl, hydroxymethyl, methoxycarbonyl or hydroxycarbonyl group; ar3 is phenyl fused to the pyrazole ring at its 1-C and 2-C positions, substituted with X and Y at the 4-C and 5-C positions, respectively, of each ring; x and Y are each O, and m and n are each 1.

The invention also provides aA pharmaceutical composition comprising a compound represented by the following formula:

ar1, Ar2 and Ar3 may each be phenyl, thienyl, pyrrolyl or furan, optionally substituted by halogen, C_1-6Alkyl, hydroxy, alkoxycarbonyl, thiocarbonyl, aminocarbonyl, hydroxycarbonyl, alkoxyalkyl, aminoalkyl or thioalkyl; each of X and Y may be O, S or NH; m is 1, 2 or 3; n is 0, 1, 2, 3 or 4. Wherein preferably, X is O, Y is O, and m is 1.

Four exemplary compounds of the invention are 1-benzyl-3- (5 '-methoxycarbonyl-2' -furan) -5, 6-methylenedioxyindazole, 1-benzyl-3- (5 '-hydroxycarbonyl-2' -furan) -5, 6-methylenedioxyindazole, 1-benzyl-3- (5 '-methoxymethyl-2' -furan) -5, 6-methylenedioxyindazole and 1-benzyl-3- (5 '-hydroxymethyl-2' -furan) -5, 6-methylenedioxyindazole. The structure of 1-benzyl-3- (5 '-hydroxycarbonyl-2' -furan) -5, 6-methylenedioxyindazole is shown below, wherein the atoms in the aromatic ring have been numbered:

the fused pyrazole compound described above includes a salt thereof, if appropriate. For example, such salts can be obtained by reacting a positively charged substituent such as an amino group with an anion. Suitable anions include, but are not limited to, chloride, an olfactory compound, iodide, sulfate, nitrate, phosphate, or acetate. Also negatively charged substituents (such as carboxylates) can form cationic salts. Suitable cations include, but are not limited to, nanoparticles, potassium particles, magnesium particles, calcium particles, and ammonium ions such as tetramethylammonium. Two examples of salts of the present invention are the hydrochloride salt of 1-benzyl-3- (5 '-aminomethyl-2' -furan) -5, 6-methylenedioxyindazole and the sodium salt of 1-benzyl-3- (5 '-carbonyl-2' -furan) -5, 6-methylenedioxyindazole.

The compounds of the invention are capable of activating sGC or of inhibiting PDES.

Thus, another aspect of the invention relates to a pharmaceutical composition comprising an effective amount of a compound of formula (I) and a pharmaceutically acceptable carrier for the treatment of a disease associated with low sGC activity, high PDE activity or platelet aggregation.

The following describes details of several embodiments of the invention. Other features, objects, and advantages of the invention will be apparent from the invention and from the claims.

Detailed description of the invention

A fused pyrazole compound of the present invention can be synthesized by the following method. Reacting an alkylenedioxyacyl chloride with an aromatic compound to provide an alkylenedioxyaryl ketone. Reacting the ketone with hydrazine to obtain a hydrazone which reacts in the presence of a first catalyst Pb (OAc)₄In the presence of the catalyst, is then converted into an intermediate product. If not purified, the intermediate product is used in the presence of a catalyst BF₃.Et₂0 is further converted to a fused pyrazole compound in the presence of a catalyst. Desired functional groups such as a hydroxycarbonyl group or an alkylcarbonyl group can be introduced into the fused pyrazole compound and thus can be obtained by further modification.

The scheme for the synthesis of the four fused pyrazole compounds 1, 2, 3 and 4 of the present invention is shown in the following figure.

Details of the synthesis of compounds 1, 2, 3 and 4 are described in examples 1, 2, 3 and 4, respectively.

The compounds of the invention can be used to increase the intracellular content of cGMP by means of activating sGC or inhibiting PDEs. Accordingly, in yet another aspect, the invention relates to a pharmaceutical composition comprising an effective amount of at least one fused pyrazole compound of formula (I) and a pharmaceutically acceptable carrier for the treatment of diseases associated with low intracellular cGMP levels, such as impotence, or diseases associated with platelet aggregation. An "effective amount" refers to the amount of the compound necessary to have a therapeutic effect in a subject being treated. The relationship of the dose (in milligrams per square body surface area) between animal and human is described in the article: freirech et al, Cancer chemi. rep., 1966, 50, 219. The body surface area may be approximately determined by the height and weight of the patient. See, for example, the article: scientific Tables, Geigy Pharmaceuticals, Ardley, N.Y., 1970, 537. As will be appreciated by those skilled in the art, the effective dosage will also vary depending upon the method of administration, excipients, and the possibility of co-use with other therapeutic methods, including the use of anti-platelet aggregation agents. Examples of carriers include colloidal silicon dioxide, magnesium stearate, cellulose, sodium lauryl sulfate, and D & Cyello # 10.

The pharmaceutical composition can be administered parenterally, such as by topical, subcutaneous, intraperitoneal, intramuscular, and intravenous administration. Examples of dosage forms for parenteral administration include aqueous solutions of the active compound, isotonic saline solution (isotonics saline), 5% dextrose solution or any other well-known pharmaceutically acceptable carrier. Solubilizers known to those skilled in the art, such as cyclodextrins or other solubilizers, can also be included in the pharmaceutical compositions described above.

The fused pyrazole compounds of the present invention may be formulated in dosage forms for other administration by well-known means, such as orally, transmucosally or subcutaneously. For example, the pharmaceutical composition may be in the form of a capsule, gel seal, or tablet for oral administration. The capsule may comprise any well-known pharmaceutically acceptable material such as gelatin or cellulose derivatives. Tablets the mixture of active compound, solid carrier and lubricant may be compressed and shaped according to conventional procedures. Examples of solid carriers include starch and sugar bentonite. The compounds may also be administered in the form of hard shell tablets or capsules containing, for example, lactose or mannitol as a binder, conventional fillers and tableting agents.

The use of fused pyrazole compounds of formula (I) for the manufacture of medicaments for the above-mentioned uses is also included in the scope of the present invention.

The compounds of the invention can be initially screened for better therapeutic efficacy in the treatment of the above-mentioned diseases by one or more of the following in vitro assays.

The efficacy of the compounds in activating sGC can be assessed in glass tubes by the following assay. Washed platelets were suspended in buffer and disrupted by sonication. The resulting lysate was centrifuged to obtain a supernatant, which was used as a substrate for sGC. An aliquot of the supernatant and the compound to be tested are added to a buffered solution containing GTP, which is the substrate of sGC. SGC activity can be measured by Gerzer et al, j. pharmacol. exp. ther, 1983, 226: 180, in accordance with the method described in (180).

The efficacy of compounds to inhibit PDEs was assessed in glass tubes by the following assay. The washed platelets were suspended in a tri-hydrochloric acid buffer (Tris-HCL buffer) and disrupted by sonication. The resulting lysate was centrifuged to obtain a supernatant containing the PDFs. An aliquot of the supernatant was removed to prepare a solution containing PDE. The compound to be tested and cGMP, which is a substrate for PDE, are added to the solution. The venom of the ophiophagus Hannah snake was then added to remove the phosphate from the 5' -GMP (converted from cGMP by PDEs) to give uncharged guanosine. Residual cGMP was removed with an ion exchange resin. The cGMP-free solution was centrifuged and an aliquot of the supernatant was removed and uncharged guanosine was metered using a liquid scintillation counter. The activity of PDEs was assessed by the amount of uncharged guanosine.

Assays in glass tubes can be used to evaluate the efficacy of the fused compounds of the invention in inhibiting platelet aggregation due to low intracellular cGMP levels. For example, the compound is cultured in a platelet suspension containing platelet aggregation factor, the degree of aggregation is measured turbidimetrically using a dual-channel lumiaggregometer, and then measured by a Teng et al, biochem, biophysis acta.1987, 924: 375-.

Screening in glass tubes can be accomplished by the following procedures well known in the art.

Without further elaboration, it is believed that one skilled in the art can, using the preceding description, utilize the present invention to its fullest extent. All articles cited herein are hereby incorporated by reference in their entirety. The following specific examples, which describe the synthesis and biological assays of various compounds of the present invention, are therefore to be considered as exemplary only and should not be construed as limiting the remainder of the invention in any way whatsoever.

Example one

Synthesis of 1-benzyl-3- (5 '-methoxycarbonyl-2' -furan) -5, 6-methylenedioxyindazole

(Compound 1)

The first step of synthesizing 5-methoxycarbonyl-2-furan 3 ', 4' -methylenedioxyphenyl ketone is as follows: anhydrous ferric chloride (0.42 g, 2.6mmol) and 3 ', 4' -methylenediphenylenechloride (52.4g, 0.3mol) were first dissolved in carbon tetrachloride (40 ml). Methyl-2-gluconate (25.2g, 0.20mmol) was then added dropwise to the above solution over a period of 10 minutes. The resulting mixture solution was heated with reflux for 36 hours and then cooled to room temperature. Water (120ml) was further added to the solution to obtain a mixture. The mixture was stirred for 1 hour and then left to stand until it separated into two layers (i.e., an aqueous layer and a carbon tetrachloride layer) and a precipitate. The precipitate was collected and dissolved in chloroform. The aqueous layer (upper layer) was extracted with chloroform. The extract was mixed with a solution of the precipitate, dehydrated with anhydrous magnesium sulfate, and filtered. Filtering under reduced pressure to remove the filtrate and obtain filter residue. The residue was recrystallized from isopropanol to give 57.1g of 5-methoxycarbonyl-2-furan 3 ', 4' -methylenedioxyphenyl ketone in a yield of 56.0%.

mp：81-82℃

MS(％)，m/z：274(M⁺)

IR(KBr)γ_max：1716，1635cm^-1(C＝O)

¹H-NMR(CDCl₃)δ：3.95(3H，s，-OCH₃)；6.08(3H，s，OCH₂O-); 7.00(2H, d, J ═ 10.2Hz, H-5); 7.27(2H, S, H-3 ', 4'); 7.56(1H, d, J ═ 1.7Hz, C2-H); and 7.79(2H, dd, J ═ 10.2, 1.7Hz, H-6).

Elemental analysis C, H (%): calculated 61.32, 3.68; the actual values were 61.32, 3.70.

6.6g (0.024mol) of 5-methoxycarbonyl-2-furan 3 ', 4' -methylenedioxyphenyl ketone was first dissolved in methanol (60 ml). Benzylhydrazine (9.0g, 0.070mol) and acetic acid (0.5ml) were then added to the ketone solution. The stream is then heated until the reaction is complete. After cooling to room temperature, its solvent was removed under vacuum to obtain a residue. The filter residue was extracted with chloroform. The extract was then washed with dilute hydrochloric acid and water, and water was removed with anhydrous magnesium sulfate. Filtering the water-removed solution, and removing the filtrate to obtain the 5-methoxycarbonylfuran methylene dioxyphenyl ketone benzyl hydrazone.

The resulting benzylhydrazone was first dissolved in dichloromethane (100 ml). The solution thus obtained was added dropwise to Pb (OAc)₄(28.2g, 0.06mol) in dichloromethanol solution (400 ml). The mixture was subsequently heated at a temperature of 30. + -. 2 ℃ for 30 minutes, followed by addition of BF₃-ET₂O (containing 47% BF)₃12 ml). The mixture was heated under reflux for 30 minutes, and then poured into ice water (1000ml) to terminate the reaction. The organic layer was separated and washed sequentially with water and 10% sodium carbonate solution, neutralized after washing, dewatered with anhydrous magnesium sulfate, filtered and concentrated in vacuo to give an oily semi-finished product. Adding ethanol into the semi-finished product, standing the mixture in refrigeratorThroughout this time, sediment formed. The collected precipitate was recrystallized from ethanol, resulting in 5.7g of Compound 1, which was obtained in a yield of 63.8%.

mp：190-192℃

MS(％)，m/z：376(M⁺)

IR(KBr)γ_max：1724cm^-1(C＝O)

¹H-NMR(CDCl₃)δ：3.93(3H，s，-OCH₃)；5.51(2H，s，＝NCH₂-)；5.98(2H，s，OCH₂O-); 6.62(1H, s, H-7); 6.91(1H, d, J ═ 3.8Hz, H-3'); 7.18-7.32(6H, m, H-4', phenyl) and 7.52(1H, s, H-4).

Elemental analysis C, H, N (%): calculated 67.02, 4.29, 7.44; the actual values were 67.12, 4.31, 7.47.

Example two

Synthesis of 1-benzyl-3- (5 '-hydroxycarbonyl-2' -furan) -5, 6-methylenedioxyindazole

(Compound 2)

Compound 1(120mg, 0.32mmol) was dissolved in a mixture of methanol (8ml) and sodium hydroxide (75 mg out of 3 ml). The solution was then heated with reflux. After cooling, the solvent was removed to obtain a residue. The residue was dissolved in water (1.5ml) and acidified with dilute HCl solution to give a precipitate. The precipitate was collected and then recrystallized from acetone to give 87.5mg of compound 2 in a yield of 75.5%.

mp：291-292℃

MS(％)，m/z：362(M⁺)

IR(KBr)γ_max：3479cm^-1(-OH)，1720cm^-1(C＝O)

¹H-NMR(DMSO-d₆)δ：5.62(2H，s，＝NCH₂-)；6.11(2H，s，OCH₂O-)；7.09(1H，d, J ═ 3.6, H-3'); 7.20-7.36(7H, m, H-7, 4', phenyl) and 7.43(1H, s, H-4).

Elemental analysis C, H, N (%): calculated values of 63.30, 3.89, 7.73; the actual values were 66.35, 3.92, 7.78.

EXAMPLE III

Synthesis of 1-benzyl-3- (5 '-hydroxymethyl-2' -furan) -5, 6-methylenedioxyindazole

(Compound 3)

Anhydrous calcium chloride (88.8mg, 0.8mmol) and sodium borohydride (60mg, 1.6mmol) were first stirred in anhydrous tetrahydrofuran (20ml) for 4 hours to obtain calcium borohydride. Then, 30ml of THF containing 101mg (0.27mmol) of Compound 1 was added dropwise to the calcium borohydride solution at a temperature of 30. + -. 2 ℃. The mixture was heated at reflux for 6 hours, cooled and then quenched. The solvent was then removed to give a solid product, which was then dissolved in 50ml of dichloromethane. Then petroleum ether was added to the dichloromethane solution to obtain a precipitate. The precipitate was collected and purified by chromatography (silica-gel-benzene) to give 84.5mg of compound 3 in 90% yield.

mp：122-123℃

MS(％)，m/z：348(M⁺)

IR(KBr)γ_max：3387cm^-1(-OH)

¹H-NMR(CDCl₃)δ：2.05(1H，br，-OH)；4.71(2H，s，-CH₂O-)；5.53(2H，s，＝NCH₂-)；5.99(2H，s，-OCH₂O-); 6.43(1H, d, J ═ 3.3Hz, H-4'); 6.61(1H, s, H-7); 6.76(1H, d, J ═ 3.3Hz, H-3') and 7.20 to 7.31(6H, m, H-4, phenyl).

Elemental analysis C, H, N (%): calculated value 68.96, 4.63, 8.04; the actual values are 68.92, 4.61, 8.01.

Example four

Synthesis of 1-benzyl-3- (5 '-methoxymethyl-2' -furan) -5, 6-methylenedioxyindazole

(Compound 4)

0.23g of Compound 1(0.66mmol) was dissolved in 5ml of tetrahydrofuran. To the solution was added 0.8g (3.3mmol) of sodium hydride at a temperature of 0. + -. 2 ℃ to give a mixture, and the mixture was allowed to react at this temperature for 0.5 hours. Then 0.1g (0.66mmol) of methyl iodide was added to the reaction mixture. The mixture was stirred for another hour and then quenched. The mixture thus obtained was extracted with dichloromethane, and the extract was neutralized with water, washed, and dehydrated with anhydrous magnesium sulfate. The solvent in the test tube was removed to give a residue which was then purified by column chromatography (silica-gel-benzene) to give 0.24g of compound 4 in 80% yield.

mp：99-101℃

MS(％)，m/z：362(M⁺)

IR(KBr)γ_max：1635cm^-1(C＝O)

¹H-NMR(CDCl₃)δ：3.42(3H，S，-OCH₃)；4.52(2H，S，-CH₂O-)；5.52(2H，S，＝NCH₂-)；5.98(2H，S，-OCH₂O-); 6.48(1H, d, j ═ 3.3Hz, H-4'); 6.61(1H, S, H-7); 6.79(1H, d, J ═ 3.3Hz, H-3'); 7.15-7.30(5H, m, H-4, phenyl) and 7.38(1H, s, H-4).

Elemental analysis C, H, N (%): calculated values of 68.60, 5.01, 7.73; the actual values are 69.58, 5.03, 7.71.

Example 5

Activation of sGC

Using Teng et al, thromb, haemiost.1988, 59: 304 to give washed rabbit platelets. They were then suspended in 50mM Tris-HCl buffer pH 7.4 and the platelets were then disrupted by sonication. The resulting lysate was centrifuged at 39,000 Xg at 4 ℃ for 20 minutesThe supernatant was used as the starting material for sGC. Two aliquots of 50ul of the supernatant were added to two 150ul of pH 7.4 trihydrochloride (50mM) buffer solutions each containing GTP (0.2mM, containing 1X 10)⁶cpm[³²P]GTP，MgCl₂(5mM), cGMP (2.5mM), sarcosine (15mM) and phosphoinositide (30 ug). One of these two solutions also contained 100uM of compound 3. After incubation at 30 ℃ for 10, GTP conversion to cGMP by sGC was stopped with HCl (200ul, 0.5N). The reaction solution was heated to 100 ℃ for 6 minutes and then cooled in an ice bath. Imidazole (200ul, 1mM) was added to each mixture immediately. GTPc and GMP are separated on neutral alumina (neutralumina) as described in White et al, anal. biochem.1971.41: 372 as described in. Measuring radioactivity in a liquid scintillation counter³²P]GTP) to determine the amount of GTP. This result indicates that compound 3 is a potent activator of sGC.

Example 6

Inhibition of PDE

Using Teng et al, biochem. 315-320 for the preparation of washed human platelets. They were then suspended in 50mM Tris-hydrochloric acid buffer pH 7.4 (containing 5mM MgCl)₂) Then platelets were disrupted by sonication at 4 ℃. The resulting lysate was centrifuged at 39,000 Xg for 20 minutes at 4 ℃ to give a supernatant containing PDEs. Two aliquots of the supernatant were removed to prepare two solutions of PDE (in triple HCl buffer), one to yield 10um of Compound 3. Both solutions were first incubated at 37 ℃ for 5 minutes, followed by addition of 10uMcGMP (containing 0.1uCi 2 [, ]³H]cGMP). The culture was further carried out at 37 ℃ for 30 minutes, during which time cGMP was converted to 5' -GMP by PDEs. Both solutions were heated to 100 ℃ for one minute and then cooled to room temperature. Venom of ophiophagus hannan snake (0.1ml, 1mg/ml) was added, followed by incubation at 25 ℃ for 30 minutes to convert 5' -GMP to guanosine. To each solution was added an ion exchange resin slurry (1.0 ml; Dowex-1, from Sigma chemical co., st. louis, MO) to bind together and remove residual cGMP. Each of the cGMP-free solutions thus obtained was centrifugedFrom this, an aliquot (0.5ml) of the supernatant was removed and the number of guanosine was counted using a liquid scintillation counter. The results indicate that compound 3 is a potent inhibitor of PDEs.

Example 7

Inhibition of platelet aggregation

EDTA was added to the blood drawn from the vein at the edge of the rabbit ear to obtain a 6mM EDTA concentrate. Blood containing EDTA was centrifuged at 90 Xg for 10 minutes at room temperature. The resulting supernatant was platelet-rich plasma and was therefore centrifuged at 500 Xg for 10 minutes. The platelet particles thus obtained were washed with a solution containing EDTA (2mM) and serum protein (3.5mg/ml), and then centrifuged at 500 Xg for another 10 minutes. The resulting granules were then washed with EDTA-free Tyrode's solution, which had the composition: NaCl (136.8g), KCl (2.8g), NaHCO₃(11.9g)，MgCl₂(1.1g)，NaH₂PO₄(0.33g)，CaCl₂(1.0g) glucose (11.2 g). After centrifugation under the same conditions, platelet particles were suspended in Tyrode's solution without EDTA as described above. The number of platelets was counted in a Coulter counter (model ZM) and adjusted to 4.5X 10⁸Platelets per ml.

The compound to be tested was added to 4 platelet suspensions and then incubated at 37 ℃ for 3 minutes under stirring conditions (900 rpm). After stirring for 1 minute, four aggregation-inducing agents, thrombin, collagen, Arachidonic Acid (AA) and Platelet Aggregation Factor (PAF), were added to the four suspensions, respectively, to generate platelet aggregation. Aggregation of platelets in each suspension can be performed using a dual channel irradiation aggregator (model 1020, payton. canada) by bornetal, j.physiol.1963, 168: 178-. The percentage value of platelet aggregation was measured 5 minutes after the addition of each aggregation inducer by Teng et al, biochem, biophysis acta.1987, 924: 375-382.

Compounds 1, 2, 3 and 4 were tested and showed inhibitory effects on platelet aggregation induced by different inducers. Among these four compounds, compound 3 is most effective in inhibiting platelet aggregation induced by thrombin, collagen, Arachidonic Acid (AA) and platelet aggregation factor.

Other embodiments

The present invention has been described in a number of embodiments. Nevertheless, various modifications of the invention will be recognized without departing from the spirit and scope of the invention. For example, the methylenedioxy group in 1-benzyl-3- (5 '-methoxycarbonyl-2' -furan) -5, 6-methylenedioxyindazole can be replaced by one or two lower methylene groups (i.e., C)_1-2) To which a fused phenyl group is attached. Accordingly, other embodiments are within the scope of the following claims.

Claims (26)

1. A fused pyrazole compound of the formula:

ar in the formula₁And Ar₂All may be phenyl, thienyl, pyrrolyl or furanyl; ar (Ar)₃Is phenyl; each of X and Y may be O or S; m is 1; n is 0, 1, 2, 3 or 4; provided that X and Y are not both O.

2. A fused pyrazole compound according to claim 1, wherein the phenyl, thienyl, pyrrolyl or furyl group is substituted with halogen, C_1-6Alkyl, hydroxy, alkoxycarbonyl, thiocarbonyl, aminocarbonyl, hydroxycarbonyl, alkoxyalkyl, aminoalkyl or thioalkyl, wherein in all groups containing alkyl or alkoxy, the number of carbon atoms in the alkyl or alkoxy is C₁-C₆。

3. A fused pyrazole compound as claimed in claim 1 or 2, wherein Ar is₂Is phenyl or furyl.

4. A fused pyrazole compound according to claim 3, wherein the phenyl or furyl group is substituted by halogen, C_1-6Alkyl, hydroxy, alkoxycarbonyl, thiocarbonyl, aminocarbonyl, hydroxycarbonyl, alkoxyalkyl, aminoalkyl or thioalkyl, wherein in all groups containing alkyl or alkoxy, the number of carbon atoms in the alkyl or alkoxy is C₁-C₆。

5. A fused pyrazole compound as claimed in claim 3 or 4, wherein Ar₁Is phenyl.

6. A fused pyrazole compound according to claim 5, wherein the phenyl group is substituted with halogen, C_1-6Alkyl, hydroxy, alkoxycarbonyl, thiocarbonyl, aminocarbonyl, hydroxycarbonyl, alkoxyalkyl, aminoalkyl or thioalkyl, wherein in all groups containing alkyl or alkoxy, the number of carbon atoms in the alkyl or alkoxy is C₁-C₆。

7. A fused pyrazole compound according to claim 1, wherein Ar is₁Is phenyl.

8. As claimed inThe fused pyrazole compound of claim 7, wherein the phenyl group is substituted with halogen, C_1-6Alkyl, hydroxy, alkoxycarbonyl, thiocarbonyl, aminocarbonyl, hydroxycarbonyl, alkoxyalkyl, aminoalkyl or thioalkyl, wherein in all groups containing alkyl or alkoxy, the number of carbon atoms in the alkyl or alkoxy is C₁-C₆。

9. A fused pyrazole compound according to claim 8, wherein Ar is₂Is furyl.

10. A fused pyrazole compound of claim 9, wherein the furyl group is substituted with halogen, C_1-6Alkyl, hydroxy, alkoxycarbonyl, thiocarbonyl, aminocarbonyl, hydroxycarbonyl, alkoxyalkyl, aminoalkyl or thioalkyl, wherein in all groups containing alkyl or alkoxy, the number of carbon atoms in the alkyl or alkoxy is C₁-C₆。

11. A fused pyrazole compound according to claim 1, wherein Ar is₂Is phenyl.

12. A fused pyrazole compound of claim 11, wherein the phenyl group is substituted with halogen, C_1-6Alkyl, hydroxy, alkoxycarbonyl, thiocarbonyl, aminocarbonyl, hydroxycarbonyl, alkoxyalkyl, aminoalkyl or thioalkyl, wherein in all groups containing alkyl or alkoxy, the number of carbon atoms in the alkyl or alkoxy is C₁-C₆。

13. A fused pyrazole compound according to claim 11 or 12, wherein Ar is₁Is phenyl.

14. A fused pyrazole compound of claim 13, wherein the phenyl group is substituted with halogen, C_1-6Alkyl, hydroxy, alkoxycarbonyl, thiocarbonyl, aminocarbonyl, hydroxyCarbonyl, alkoxyalkyl, aminoalkyl or thioalkyl, in which the number of carbon atoms in the alkyl or alkoxy radical is C in all radicals containing alkyl or alkoxy groups₁-C₆。

15. A fused pyrazole compound as claimed in claim 1 or 2, wherein Ar is₂Is phenyl or furyl.

16. A fused pyrazole compound of claim 15, wherein the phenyl or furyl group is substituted with halogen, C_1-6Alkyl, hydroxy, alkoxycarbonyl, thiocarbonyl, aminocarbonyl, hydroxycarbonyl, alkoxyalkyl, aminoalkyl or thioalkyl, wherein in all groups containing alkyl or alkoxy, the number of carbon atoms in the alkyl or alkoxy is C₁-C₆。

17. A fused pyrazole compound according to claim 15 or 16, wherein Ar₂Is phenyl or furyl.

18. A fused pyrazole compound of claim 17, wherein the phenyl or furyl group is substituted with halogen, C_1-6Alkyl, hydroxy, alkoxycarbonyl, thiocarbonyl, aminocarbonyl, hydroxycarbonyl, alkoxyalkyl, aminoalkyl or thioalkyl, wherein in all groups containing alkyl or alkoxy, the number of carbon atoms in the alkyl or alkoxy is C₁-C₆。

19. A fused pyrazole compound according to claim 18, wherein Ar is₁Is phenyl.

20. A fused pyrazole compound of claim 19, wherein the phenyl group is substituted with halogen, C_1-6Alkyl, hydroxy, alkoxycarbonyl, thiocarbonyl, aminocarbonyl, hydroxycarbonyl, alkoxyalkyl, aminoalkyl or thioalkyl, all of which comprise alkyl or alkaneIn the group of oxy, the alkyl or alkoxy group has C as the carbon atom₁-C₆。

21. A fused pyrazole compound as claimed in claim 1 or 2, wherein Ar is₁Is phenyl; ar (Ar)₂Is furyl, which is attached to the pyrazole ring at its 2-C position and is substituted at its 5-C position by methoxymethyl, hydroxymethyl, methoxycarbonyl or hydroxycarbonyl groups; ar (Ar)₃Is phenyl, which is fused to the pyrazole ring at its 1-C and 2-C positions and is substituted by X and Y at the 4-C and 5-C positions of each ring, respectively; each of m and n is 1.

22. A pharmaceutical composition comprising a compound of the formula:

each Ar in the formula₁And Ar₂All may be phenyl, thienyl, pyrrolyl or furanyl; ar (Ar)₃Is phenyl; each of X and Y may be O or S; m is 1; n is 0, 1, 2, 3 or 4; provided that X and Y are not both O at the same time.

23. The pharmaceutical composition of claim 22, wherein the phenyl, thienyl, pyrrolyl or furyl group is substituted with halogen, C_1-6Alkyl, hydroxy, alkoxycarbonyl, thiocarbonyl, aminocarbonyl, hydroxycarbonyl, alkoxyalkyl, aminoalkyl or thioalkyl, wherein in all groups containing alkyl or alkoxy, the number of carbon atoms in the alkyl or alkoxy is C₁-C₆。

24. The pharmaceutical composition of claim 22 or 23, wherein Ar is₂Is phenyl or furyl.

25. A pharmaceutical composition comprising a compound of the structure:

26. a fused pyrazole compound having the structure: