JP2002179644A - Tetracyclic aromatic compound - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a compound having small absorption in a visible region, and high birefringence. SOLUTION: This tetracyclic aromatic compound is represented by formula (I) [wherein, L1 and L3 are each independently CH=CH or CH=C; L2 is a single bond, CH2CH2, C=C or CH≡C; and at least one of benzene rings A, B, C and D has a substituent, and at least one of the substituent is sulfo, carboxy or a salt thereof, and two or more substituents may form a ring by bonding to each other].

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a novel tetracyclic aromatic compound. In particular, the present invention relates to a tetracyclic aromatic compound exhibiting high optical anisotropy.

[0002]

2. Description of the Related Art An aromatic compound represented by the following formula (X) is known from various literatures (eg, Collect. Czech. Chem. Commu.).
n.; 23; 1958; 915-921; Chem. Ber.; 36; 1903; 2976).

[0003]

Embedded image

In the formula (X), L is a single bond, -CH
₂ —CH ₂ —, —CH ＝ CH— or —C≡C—. Y is -N = NR or -NR ₂ and R is
Is a hydrogen atom or a substituent. The literature (Collect.
Czech.Chem.Commun.; 23; 1958; 915-921, Chem.Be
r.; 36; 1903; 2976) describe an ultraviolet absorber, a fluorescent whitening agent, a dye and a synthetic intermediate thereof as uses of the aromatic compound represented by the formula (X).

[0005]

As a result of the study of the present inventors, it has been found that the aromatic compound represented by the formula (X) has optical anisotropy. Then, the present inventor studied applying the aromatic compound represented by the formula (X) to an optical material requiring optical anisotropy (a retardation film or an anisotropic scattering film). However, the aromatic compound represented by the formula (X) has a large coloring and an insufficient optical anisotropy (birefringence), so that it has been difficult to apply it to an optical material. An object of the present invention is to provide a compound having a small absorption in the visible region and a high birefringence.

[0006]

Means for Solving the Problems The present invention provides the following (1) to
(7) A tetracyclic aromatic compound is provided. (1) A tetracyclic aromatic compound represented by the following formula (I):

[0007]

Embedded image

Wherein L ¹ and L ³ are each independently —CH ＝ CH— or —C≡C—; L ² is
Single _{bond, -CH 2 -CH 2 -, -} CH = CH- or -
C≡C—; and at least one of the benzene rings A, B, C and D has a substituent, and at least one substituent is a sulfo, a carboxyl or a salt thereof; And the groups may combine to form a ring]. (2) The tetracyclic aromatic compound according to (1), wherein in formula (I), L ¹ and L ³ are each —C≡C—. (3) In the formula (I), L ² is a single bond or —CH
The tetracyclic aromatic compound according to (1), wherein ＣＨCH—.

(4) In the formula (I), a benzene ring A,
The tetracyclic aromatic compound according to (1), wherein at least two of B, C, and D have a substituent, and at least four substituents are sulfo, carboxyl, or a salt thereof. (5) The tetracyclic aromatic compound according to (1), wherein in Formula (I), the benzene rings B and C are each substituted with sulfo, carboxyl, or a salt thereof. (6) The tetracyclic aromatic compound according to (5), wherein in Formula (I), the benzene rings B and C are each substituted with sulfo or a salt thereof. (7) A tetracyclic aromatic compound represented by the following formula (IIa), (IIb) or (IIc):

[0010]

Embedded image

Wherein M is a cation and M may be dissociated; and the benzene rings A, B, C and D may have a substituent, And the groups may combine to form a ring].

[0012]

As a result of the study of the present inventors, it has been found that the tetracyclic aromatic compound represented by the formula (I) has a small absorption in the visible region and a high birefringence. By using this tetracyclic aromatic compound, an optical material having low coloring and high optical anisotropy can be manufactured.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The tetracyclic aromatic compound of the present invention comprises
It is represented by the following formula (I).

[0014]

Embedded image

In the formula (I), L ¹ and L ³ are each independently —CH ＝ CH— or —C≡C—. L ¹ and L ³ are preferably each —C≡C—. -CH = CH- is more preferably a trans type than a cis type. In the formula (I), L ² represents a single bond, —CH ₂ —CH ₂ —, —CH ＝ CH— or —C≡
C-. L ² is a single bond, -CH = CH- or -
Preferably, C≡C—, a single bond or —CH ＝
It is more preferably CH-, and most preferably -CH = CH-. -CH = CH- is more preferably a trans type than a cis type.

In the formula (I), benzene rings A, B, C
And at least one of D has a substituent. Examples of the substituent include a halogen atom, amino, hydroxyl, sulfo (and its salt), carboxyl (and its salt),
Phosphinico (and its salt), phosphono (and its salt), phosphinicooxy (and its salt), phosphonooxy (and its salt), aliphatic group, aromatic group, heterocyclic group, -OR, -CO -R, -O-CO-R, -CO-
O-R, -SO-R, -SO 2 -R, include -NH-R and -NR-NH-R. R is an aliphatic group, an aromatic group or a heterocyclic group.

In the present specification, the aliphatic group includes an alkyl group, a substituted alkyl group, an alkenyl group, a substituted alkenyl group, an alkynyl group and a substituted alkynyl group. The aliphatic group may have a cyclic structure or a branched structure.
The number of carbon atoms in the aliphatic group is preferably 1 to 15, more preferably 1 to 10, and most preferably 1 to 5. Examples of the substituent of the substituted alkyl group, the substituted alkenyl group and the substituted alkynyl group include:
Halogen atom, amino, hydroxyl, sulfo (and its salt), carboxyl (and its salt), phosphinico (and its salt), phosphono (and its salt), phosphinicooxy (and its salt), phosphonooxy (and its salt) ), Aromatic group, heterocyclic group, -OR, -CO
-R, -O-CO-R, -CO-OR, -SO-R,
-SO ₂ -R, include -NH-R and -NR-NH-R. R is an aliphatic group, an aromatic group or a heterocyclic group. The substituted alkyl group also includes an epoxyalkyl group.

In the present specification, the aromatic group includes an aryl group and a substituted aryl group. The aryl part of the aryl group and the substituted aryl group is preferably phenyl or naphthyl, more preferably phenyl. Examples of the substituent of the substituted aryl group include a halogen atom, amino, hydroxyl, sulfo (and a salt thereof),
Carboxyl (and its salt), phosphinico (and its salt), phosphono (and its salt), phosphinicooxy (and its salt), phosphonooxy (and its salt), aliphatic group, aromatic group, heterocyclic group, -OR, -C
OR, -O-CO-R, -CO-OR, -SO-
_{R, -SO 2 -R, -NH-} R and -NR-NH-R
Is included. R is an aliphatic group, an aromatic group or a heterocyclic group. In the present specification, the heterocyclic group includes an unsubstituted heterocyclic group and a substituted heterocyclic group. The heterocyclic ring of the heterocyclic group preferably has aromaticity. The aromatic heterocycle is an unsaturated heterocycle and generally has the most double bonds. The heterocycle is preferably a 5- or 6-membered ring. Another heterocyclic ring, aromatic ring or aliphatic ring may be condensed to the heterocyclic ring. Examples of the substituent of the substituted heterocyclic group are the same as the examples of the substituent of the substituted aryl group.

In the formula (I), at least one substituent is a sulfo, a carboxyl or a salt thereof.
Sulfo and carboxyl may have a proton dissociated. Examples of cations that form salts with sulfo or carboxyl include alkali metal ions (eg, sodium ions, potassium ions), alkaline earth metal ions (eg, calcium ions), ammonium ions and organic ammonium ions (primary to tertiary). Quaternary amine ions and quaternary ammonium ions). Alkali metal ions are particularly preferred. The number of substituents that are sulfo, carboxyl, or a salt thereof is preferably two, four, or six.

In the formula (I), benzene rings A, B, C
It is preferred that at least two of D and D have a substituent. It is also preferable that at least two substituents are sulfo, carboxyl or a salt thereof, and it is more preferable that at least four substituents are sulfo, carboxyl or a salt thereof. In the formula (I),
It is also preferred that the benzene rings B and C are each substituted with sulfo, carboxyl or a salt thereof, and it is more preferred that the benzene rings B and C are each substituted with sulfo or a salt thereof. The substitution position of the benzene ring B and C, it is particularly preferred L ² is a carbon atom adjacent to the carbon atom bonded (o-position relative to L ^2).

Depending on the use of the aromatic compound, it may be preferable to introduce a polymerizable group as a substituent for the benzene rings A, B, C and D. As the polymerizable group, an alkenyl group, a substituted alkenyl group and an epoxyalkyl group are preferred, and an alkenyl group and a substituted alkenyl group are more preferred. When a polymerizable group is introduced, it is preferable that at least two polymerizable groups be substituents on the benzene rings A, B, C and D.

In the formula (I), two substituents may combine to form a ring. The ring to be formed is preferably a condensed ring of a benzene ring (A, B, C or D). The ring to be formed includes an aromatic ring, an aliphatic ring and a hetero ring. The ring formed is preferably an aromatic ring, and more preferably a benzene ring. However, it is preferable that the two substituents do not bond (do not form a ring).

Particularly preferred tetracyclic aromatic compounds are represented by the following formulas (IIa) to (IIc).

[0024]

Embedded image

In the formulas (IIa) to (IIc), M is a cation, and M may be dissociated. Examples of cations include protons, alkali metal ions (eg, sodium ions, potassium ions), alkaline earth metal ions (eg, calcium ions), ammonium ions and organic ammonium ions (primary to tertiary amine ions and Grade ammonium ions). Protons and alkali metal ions are particularly preferred. Formula (IIa)-
In (IIc), the benzene rings A, B, C and D are
It may have a substituent. For definitions and examples of substituents, see
The same as in formula (I). In the formulas (IIa) to (IIc), two substituents may combine to form a ring. The ring to be formed is the same as in formula (I).

The following are examples of the tetracyclic aromatic compound represented by the formula (I).

[0027]

Embedded image

[0028]

Embedded image

[0029]

Embedded image

[0030]

Embedded image

[0031]

Embedded image

[0032]

Embedded image

[0033]

Embedded image

[0034]

Embedded image

[0035]

Embedded image

[0036]

Embedded image

[0037]

Embedded image

[0038]

Embedded image

[0039]

Embedded image

[0040]

Embedded image

[0041]

Embedded image

[0042]

Embedded image

[0043]

Embedded image

[0044]

Embedded image

[0045]

Embedded image

[0046]

Embedded image

The tetracyclic aromatic compound represented by the formula (I) includes, for example, styrene, ethynylbenzene or a derivative thereof represented by the following formula (III) and a derivative represented by the following formula (IV). , 4′-dihalogenobiphenyl, di (4-halogenophenyl) ethane, di (4-halogenophenyl) ethylene, di (4-halogenophenyl) acetylene or a derivative thereof.

[0048]

Embedded image

In the formula (III), L ¹ represents —CH ＝ CH
-Or -C≡C-. In the formula (III), the benzene ring A may have a substituent. The substituents on the benzene ring A are the same as the substituents on the benzene rings A and D in the formula (I). In the formula (IV), L
² is a single _{bond, -CH 2 -CH 2 -, -} CH = CH- or -C≡C-. In the formula (IV), the benzene rings B and C may have a substituent. The substituents on the benzene rings B and C are the same as the substituents on the benzene rings B and C in the formula (I). In the formula (IV), X is a halogen atom.

When the compound of the formula (III) is used in twice the molar amount of the compound of the formula (IV), two identical substituents can be introduced. Alternatively, only one halogen atom of the compound of formula (IV) is replaced by the compound of formula (III), the resulting compound is isolated, and the remaining halogen atom is replaced by another compound of formula (III). Is also good.

The reaction of replacing a halogen atom bonded to an aromatic ring with a sp2 carbon or a sp-bonded carbon is widely known. The above reaction is also an application. Preferably, the reaction proceeds in the presence of a base using a palladium compound as a catalyst. As the reaction solvent, an organic solvent (eg, ethyl acetate, methyl ethyl ketone, toluene, benzene, methanol, ethanol, isopropyl alcohol, dimethylformamide, dimethylacetamide, dimethylsulfoxide, sulfolane, dioxane, tetrahydrofuran, diethylene glycol, ethylene glycol dimethyl ether) or an inorganic solvent (Eg, water) is used.
The amount of the reaction solvent used is 1 part of the compound of the formula (IV) by mass ratio.
A factor of 2 to 50 is preferred.

Examples of the base include potassium carbonate, sodium hydroxide, piperidine, pyridine, triethylamine. When the base is a liquid, the liquid base can also function as a reaction solvent. The amount of the base used is preferably 1 to 10 times the molar amount of the compound of the formula (IV). However,
Larger amounts can be used if a liquid base is to function as the reaction solvent. Examples of the palladium compound used as a catalyst include (Ph ₃ P) ₂ PdCl ₂ ,
_{Pd (PPh 3) 4, Pd} -C , and Pd (OAc) ₂
Is included. Ph is phenyl and Ac is acetyl. When a monovalent copper compound (eg, CuI, CuBr) or an organic phosphorus compound (eg, triphenylphosphine) is added, the reaction sometimes proceeds well. The amount of the catalyst and other additives used is preferably 0.1 to 100 mol% of the compound of the formula (IV). The reaction temperature is 20 to 12
Preferably it is 0 ° C. The reaction time is from 6 minutes to 10 minutes.
It is preferably 0 hours.

The compound synthesized by the above reaction may be further subjected to a reaction (for example, a substituent addition reaction). In addition, a salt can be formed by adding a counter ion.

The styrene, ethynylbenzene or a derivative thereof represented by the above formula (III) can be obtained by reacting halogenobenzene or a derivative thereof with ethylene, acetylene or a derivative thereof, and deprotecting if necessary. , Can be synthesized.

4,4'-dihalogenobiphenyl, di (4-halogenophenyl) ethane represented by the formula (IV),
Di (4-halogenophenyl) ethylene, di (4-halogenophenyl) acetylene or derivatives thereof are 4,4′-diaminobiphenyl, di (4-aminophenyl) ethane, di (4-aminophenyl) ethane represented by the following formula (VII). It can be synthesized by performing a Sandmeyer reaction on (4-aminophenyl) ethylene, di (4-aminophenyl) acetylene, or a derivative thereof.

[0056]

Embedded image

In the formula (VII), L ² is a single bond, -C
H ₂ —CH ₂ —, —CH ＝ CH— or —C≡C—. In the formula (VII), the benzene rings B and C may have a substituent. The substituents on the benzene rings B and C are the same as the substituents on the benzene rings B and C in the formula (I).

The tetracyclic aromatic compound (23) can be prepared by a known method (for example, Z. Electrocchem. Angew. Phys. Chem .;
9; 1903, 416-419, Helv. Chim. Acta .; 9; 1926,949
Described), an amine having a single bond outside the ring is synthesized,
Then, it can be synthesized by performing the same reaction as in Example 1 described later. The tetracyclic aromatic compound (37) can be produced by a known method (for example, described in J. Chem. Soc .; 93; 1908; 1724).
According to the above, a nitro compound having a exocyclic double bond is synthesized and reduced, and then the same reaction as in Example 1 described later is performed, whereby a tetracyclic aromatic compound (37) can be synthesized. The tetracyclic aromatic compound (38) can be produced by a known method (for example, J. Am.
Amer. Chem. Soc .; 46; 1924; 1921), a nitro compound having a single bond outside the ring is synthesized and reduced, and then the same reaction as in Example 1 described later is performed. The tetracyclic aromatic compound (39) is synthesized and reduced according to a known method (for example, described in J. Chem. Soc .; 93; 1908; 1724), Thereafter, the same reaction as in Example 1 described later was performed to synthesize a tetracyclic aromatic compound (39).

[0059]

[Example 1] Synthesis of tetracyclic aromatic compound (1) 2.16 g (54 mmol) of sodium hydroxide was dissolved in 64 ml of water, and 10 g (2) of the following compound (a) was further dissolved.
7 mmol) and dissolved. The compound (a)
Is a reagent commercially available as an aniline derivative. 20 ml of 40% by mass hydrobromic acid was added and cooled with ice. 30 minutes later, 3.72 g (54 mmol) of sodium nitrite was added to 16 ml of water.
The solution was added and stirred for 2 hours while cooling with ice. 10.14 g (70.2 mmol) of copper bromide was added to 56 ml of 40% by mass hydrobromic acid, and the above reaction solution was added dropwise while stirring at 70 ° C. After the bubbling subsided, the mixture was allowed to cool, and the crystals were taken into consideration and washed with water to obtain 6.8 g (13.6 mmol) of the following compound (b).

[0060]

Embedded image

3 g (6 mmol) of the compound (b) and 1.98 microliter (18 mmol) of ethynylbenzene
Was added to 18 ml of dimethylformamide (DMF), and the mixture was stirred under a nitrogen stream. (Ph ₃ P) ₂ PdCl ₂ 210
mg (0.30 mmol) and 114 mg of copper (I) iodide
(0.6 mmol) and 7 ml of triethylamine were added, and the mixture was stirred for 10 hours in a 90 ° C. oil bath connected with a nitrogen balloon instead of a nitrogen stream. After cooling, add 1
N-hydrochloric acid solution is added to make it acidic, and it is formed on a Sephadex column, and a tetracyclic aromatic compound containing two molecules of water (1)
1.4 g (2.4 mmol) were obtained. ¹ H NMR (deuterated DMSO): δ = 8.22 (s, 2
H), 7.97 (s, 2H), 7.71 (d, 2H),
7.69 to 7.53 (m, 6H), 7.53 to 7.39
(M, 6H) Elemental analysis: H 4.59% (theoretical 4.20%), C6
1.72% (theoretical value 62.49%), N 0.3% or less (theoretical value 0%)

Example 2 Synthesis of Tetracyclic Aromatic Compound (9) A tetracyclic aromatic compound (9) was synthesized in the same manner as in Example 1. ¹ H NMR (deuterated DMSO): δ = 8.19 (s, 2
H), 7.97 (s, 2H), 7.65 (d, 2H),
7.60 to 7.40 (br, 6H), 6.90 to 7.0
0 (m, 4H), 4.09 (q, 4H), 1.37
(T, 6H)

[Example 3] Synthesis of tetracyclic aromatic compound (10) In the same manner as in Example 1, tetracyclic aromatic compound (10)
Was synthesized. ¹ H NMR (deuterated DMSO): δ = 8.19 (s, 2
H), 7.90 (s, 2H), 7.61 (d, 2H),
7.50 (m, 3H), 7.40 (t, 2H), 7.1
1 (d, 2H), 6.99 (t, 2H), 3.90
(S, 6H)

Example 4 Synthesis of Tetracyclic Aromatic Compound (11) In the same manner as in Example 1, tetracyclic aromatic compound (11)
Was synthesized. ¹ H NMR (deuterated DMSO): δ = 8.20 (s, 2
H), 7.95 (s, 2H), 7.66 (d, 2H),
7.51 (m, 6H), 6.96 (d, 4H), 3.8
1 (s, 6H)

Example 5 Synthesis of tetracyclic aromatic compound (12) In the same manner as in Example 1, tetracyclic aromatic compound (12)
Was synthesized. ¹ H NMR (deuterated DMSO): δ = 8.20 (s, 2
H), 7.91 (s, 2H), 7.68 (d, 2H),
7.55 (d, 2H), 7.33 (t, 2H), 7.1
4 (m, 4H), 6.98 (d, 2H), 3.81
(S, 6H)

Example 6 Synthesis of Tetracyclic Aromatic Compound (13) In the same manner as in Example 1, tetracyclic aromatic compound (13)
Was synthesized. ¹ H NMR (deuterated DMSO): δ = 8.20 (s, 2
H), 7.91 (s, 2H), 7.67 (d, 2H),
7.51 (m, 6H), 7.25 (d, 4H), 2.6
0 (t, 4H), 1.59 (m, 4H), 1.40-
1.20 (m, 8H), 0.89 (t, 6H)

Example 7 Synthesis of tetracyclic aromatic compound (14) In the same manner as in Example 1, tetracyclic aromatic compound (14)
Was synthesized. ¹ H NMR (deuterated DMSO): δ = 8.22 (s, 2
H), 7.99 (s, 2H), 7.83 (d, 4H),
7.77 (d, 4H), 7.70 (d, 2H), 7.5
9 (d, 2H)

Example 8 Synthesis of tetracyclic aromatic compound (15) In the same manner as in Example 1, tetracyclic aromatic compound (15)
Was synthesized. ¹ H NMR (deuterated DMSO): δ = 8.25 (s, 2
H), 8.23 (s, 2H), 8.15-7.82
(M, 8H), 7.82 to 7.40 (m, 10)

Example 9 Synthesis of tetracyclic aromatic compound (16) In the same manner as in Example 1, tetracyclic aromatic compound (16)
Was synthesized. ¹ H NMR (heavy water): δ = 8.04 (s, 2H), 7.
94 (s, 2H), 7.86 (d, 2H), 7.80-
7.55 (m, 10H)

Example 10 Synthesis of Tetracyclic Aromatic Compound (21) A known method (for example, Z. Electrocchem. Angew. Phys.
Chem .; 9; 1903, 416-419, Helv. Chim. Acta .; 9; 192
6,949), and an amine having a exocyclic triple bond was synthesized. Thereafter, the same reaction as in Example 1 was performed to synthesize a tetracyclic aromatic compound (21).

Example 11 Synthesis of tetracyclic aromatic compound (4) 200 mg (2.0 mmol) of potassium acetate was dissolved in 5 ml of methanol, and the tetracyclic aromatic compound was dissolved with stirring.
(1) 200 mg (0.37 mmol) was added. After heating and stirring for 5 minutes, the mixture was allowed to cool. The crystals are collected by filtration, washed with methanol, and tetracyclic aromatic compounds containing three molecules of water.
(4) 150 mg (0.24 mmol) was obtained. Elemental analysis: H 3.98% (theoretical 3.61%), C5
3.43% (theoretical value 53.71%), N 0.3% or less (theoretical value 0%), K12.2% (theoretical value 11.66%)

Example 12 Synthesis of Tetracyclic Aromatic Compound (29) A known method (for example, Bull. Soc. Chim. Fr. 4, 49 (193)
1) 1.3 of the following compound (c) synthesized according to 1047-1049)
g (2.75 mmol) was reacted in the same manner as in Example 1 to obtain a tetracyclic aromatic compound (29) 10
0 mg (0.194 mmol) were obtained. ¹ H NMR (deuterated DMSO): δ = 7.99 (s, 2
H), 7.57 (m, 4H), 7.50-7.0 (m,
10H)

[0073]

Embedded image

Example 13 Synthesis of Tetracyclic Aromatic Compound (33) 1 g (2 mmol) of the compound (b) synthesized in Example 1 and 687 microliter (6 mmol) of styrene were dissolved in dimethylformamide (DMF). 8 ml, and the mixture was stirred under a nitrogen stream. 9 mg (0.04 mmol) of Pd (OAc) ₂ , tris (2-methylphenyl) phosphine 4
8.7 mg (0.16 mmol) and 1.39 ml (10 mmol) of triethylamine were added, and a nitrogen balloon was connected in place of a nitrogen stream.
Stirred for hours. After cooling, the reaction solution was acidified by adding 1N aqueous hydrochloric acid, and the mixture was formed on a Sephadex column. 0.6 g (1.08 mmol) of a tetracyclic aromatic compound (33) was obtained.
I got ¹ H NMR (deuterated DMSO): δ = 8.19 (s, 2
H), 8.02 (s, 2H), 7.70-7.52
(M, 8H), 7.45 to 7.10 (m, 10H)

Example 14 Preparation of Optical Film A tetracyclic aromatic compound (1) (200 mg) was dissolved in 750 microliter of 1N sodium hydroxide. A 10 microliter portion thereof was placed on a slide glass and sheared with a bar coater to produce a transparent optical film having a film having high birefringence on a transparent support.

Claims (7)

[Claims] 1. A tetracyclic aromatic compound represented by the following formula (I): [Wherein L ¹ and L ³ are each independently -CH =
CH- or a -C≡C-; L ² is a single bond, -C
H ₂ —CH ₂ —, —CH ＝ CH— or —C≡C—; and at least one of the benzene rings A, B, C and D has a substituent, and at least one substituent is ,
Sulfo, carboxyl or a salt thereof, and two substituents may combine to form a ring]. 2. In the formula (I), L ¹ and L ³ are
The tetracyclic aromatic compound according to claim 1, wherein each of -C≡C-. 3. The tetracyclic aromatic compound according to claim 1, wherein in the formula (I), L ² is a single bond or —CH ＝ CH—. 4. In the formula (I), a benzene ring A, B,
The tetracyclic aromatic compound according to claim 1, wherein at least two of C and D have a substituent, and at least four substituents are sulfo, carboxyl, or a salt thereof. 5. The tetracyclic aromatic compound according to claim 1, wherein, in the formula (I), the benzene rings B and C are each substituted with sulfo, carboxyl or a salt thereof. 6. The tetracyclic aromatic compound according to claim 5, wherein in the formula (I), the benzene rings B and C are each substituted by sulfo or a salt thereof. 7. The compound represented by the following formula (IIa), (IIb) or (II)
Tetracyclic aromatic compound represented by c): Wherein M is a cation and M may be dissociated; and the benzene rings A, B, C and D may have a substituent, and the two substituents To form a ring].