New Naphtho[2,3-B]Furan Derivatives

A compound represented by formula (I):

• or a pharmaceutically acceptable salt thereof, wherein
• X is an oxygen atom or sulfur atom;
• R1 is a hydrogen atom, a cyano group, a trifluoromethyl group, a trifluoromethoxy group, an optionally substituted C1-6alkyl group, an optionally substituted C2-6alkenyl group, an optionally substituted C2-6alkynyl group, an optionally substituted C3-10cycloalkyl group, an optionally substituted C3-10cycloalkenyl group, an optionally substituted 3 to 10-membered saturated heterocyclic group, an optionally substituted C6-10aryl group, an optionally substituted 5 to 12-membered monocyclic or polycyclic heteroaryl group, —OR4, or —SR4;
• each R2 is independently a halogen atom, a cyano group, a nitro group, a trifluoromethyl group, a trifluoromethoxy group, an optionally substituted C1-6alkyl group, an optionally substituted C2-6alkenyl group, an optionally substituted C2-6alkynyl group, an optionally substituted C3-10cycloalkyl group, an optionally substituted C3-10cycloalkenyl group, an optionally substituted C1-6alkylcarbonyl group, an optionally substituted C3-10cycloalkylcarbonyl group, an optionally substituted C6-10arylcarbonyl group, an optionally substituted 5 to 12-membered monocyclic or polycyclic heteroarylcarbonyl group, an optionally substituted 3 to 10-membered saturated heterocyclic group, an optionally substituted C6-10aryl group, an optionally substituted 5 to 12-membered monocyclic or polycyclic heteroaryl group, an optionally substituted C1-6alkylsulfonyl group, an optionally substituted C3-10cycloalkylsulfonyl group, an optionally substituted C6-10arylsulfonyl group, an optionally substituted aminosulfonyl group, —N(R′)2, or —SR4;
• each R3 is independently a hydrogen atom, an optionally substituted C1-6alkyl group, an optionally substituted C2-6alkenyl group, an optionally substituted C2-6alkynyl group, an optionally substituted C3-10cycloalkyl group, an optionally substituted C3-10cycloalkenyl group, an optionally substituted 3 to 10-membered saturated heterocyclic group, an optionally substituted C6-10aryl group, an optionally substituted 5 to 12-membered monocyclic or polycyclic heteroaryl group, an optionally substituted C1-6alkylcarbonyl group, an optionally substituted C3-10cycloalkylcarbonyl group, an optionally substituted C6-10arylcarbonyl group, an optionally substituted 3 to 10-membered saturated heterocyclylcarbonyl group, an optionally substituted 5 to 12-membered monocyclic or polycyclic heteroarylcarbonyl group, an optionally substituted C1-6alkyloxycarbonyl group, an optionally substituted C3-10cycloalkyloxycarbonyl group, an optionally substituted C6-10aryloxycarbonyl group, an optionally substituted 3 to 10-membered saturated heterocyclyloxycarbonyl group, an optionally substituted 5 to 12-membered monocyclic or polycyclic heteroaryloxycarbonyl group, an optionally substituted C1-6alkylaminocarbonyl group, an optionally substituted C3-10cycloalkylaminocarbonyl group, an optionally substituted C6-10arylaminocarbonyl group, an optionally substituted 3 to 10-membered saturated heterocyclylaminocarbonyl group, or an optionally substituted 5 to 12-membered monocyclic or polycyclic heteroarylaminocarbonyl group;
• m is O, 1, 2, 3, or 4 and n is 1, 2, 3, or 4, with the proviso that the sum of m and n is 1, 2, 3, or 4;
• and
• each R4 is independently a hydrogen atom, an optionally substituted C1-6alkyl group, an optionally substituted C2-6alkenyl group, an optionally substituted C2-6alkynyl group, an optionally substituted C3-10cycloalkyl group, an optionally substituted C3-10cycloalkenyl group, an optionally substituted 3 to 10-membered saturated heterocyclic group, an optionally substituted C6-10aryl group, or an optionally substituted 5 to 12-membered monocyclic or polycyclic heteroaryl group, or when two R4 are attached to a nitrogen atom, the two R4 may be taken together with the nitrogen atom to which they are attached to form a nitrogen-containing 3 to 10-membered saturated heterocyclic group,
• with the proviso that the following compounds are excluded:
• 5-hydroxy-4,9-dioxo-4,9-dihydronaphtho[2,3-b]furan-2-carbaldehyde;
• 2-acetyl-5-hydroxynaphtho[2,3-b]furan-4,9-dione;
• 2-acetyl-8-hydroxynaphtho[2,3-b]furan-4,9-dione;
• 2-acetyl-6-methoxynaphtho[2,3-b]furan-4,9-dione;
• 2-acetyl-7-methoxynaphtho[2,3-b]furan-4,9-dione;
• 2-acetyl-8-methoxynaphtho[2,3-b]furan-4,9-dione;
• 2-acetyl-5-methoxynaphtho[2,3-b]furan-4,9-dione;
• 2-acetyl-8-hydroxy-7-methoxynaphtho[2,3-b]furan-4,9-dione;
• 2-acetyl-6,7-di methoxynaphtho[2,3-b]furan-4,9-dione;
• 2-acetyl-7,8-dimethoxynaphtho[2,3-b]furan-4,9-dione;
• 2-acetyl-5,6-dimethoxynaphtho[2,3-b]furan-4,9-dione;
• 2-benzoyl-5-hydroxynaphtho[2,3-b]furan-4,9-dione;
• 8-hydroxy-4,9-dioxo-4,9-dihydronaphtho[2,3-b]thiophene-2-carbaldehyde;
• 5-hydroxy-4,9-dioxo-4,9-dihydronaphtho[2,3-b]thiophene-2-carbaldehyde;
• 8-methoxy-4,9-dioxo-4,9-dihydronaphtho[2,3-b]thiophene-2-carbaldehyde;
• 8-hydroxy-4,9-dioxo-4,9-dihydronaphtho[2,3-b]thiophene-2-carboxylic acid;
• 2-acetyl-8-hydroxynaphtho[2,3-b]thiophene-4,9-dione;
• 2-acetyl-5-hydroxynaphtho[2,3-b]thiophene-4,9-dione;
• 2-acetyl-5,8-dihydroxynaphtho[2,3-b]thiophene-4,9-dione;
• 8-hydroxy-2-propanoylnaphtho[2,3-b]thiophene-4,9-dione;
• 2-acetyl-8-methoxynaphtho[2,3-b]thiophene-4,9-dione;
• 8-methoxy-4,9-dioxo-4,9-dihydronaphtho[2,3-b]thiophene-2-carboxylic acid;
• methyl 8-hydroxy-4,9-dioxo-4,9-dihydronaphtho[2,3-b]thiophene-2-carboxylate;
• methyl 5-hydroxy-4,9-dioxo-4,9-dihydronaphtho[2,3-b]thiophene-2-carboxylate;
• 8-hydroxy-2-(2-methylpropanoyl)naphtho[2,3-b]thiophene-4,9-dione;
• 2-acetyl-8-hydroxy-7-(hydroxymethyl)naphtho[2,3-b]thiophene-4,9-dione;
• 2-acetyl-5,8-dimethoxynaphtho[2,3-b]thiophene-4,9-dione;
• 8-methoxy-2-propanoylnaphtho[2,3-b]thiophene-4,9-dione;
• ethyl 8-hydroxy-4,9-dioxo-4,9-dihydronaphtho[2,3-b]thiophene-2-carboxylate;
• 8-hydroxy-2-(thiophene-2-ylcarbonyl)naphtho[2,3-b]thiophene-4,9-dione;
• 8-methoxy-2-(2-methylpropanoyl)naphtho[2,3-b]thiophene-4,9-dione;
• 2-benzoyl-5-hydroxynaphtho[2,3-b]thiophene-4,9-dione;
• 2-benzoyl-8-hydroxynaphtho[2,3-b]thiophene-4,9-dione;
• propan-2-yl 8-hydroxy-4,9-dioxo-4,9-dihydronaphtho[2,3-b]thiophene-2-carboxylate;
• ethyl 8-methoxy-4,9-dioxo-4,9-dihydronaphtho[2,3-b]thiophene-2-carboxylate;
• 8-methoxy-2-(thiophene-2-ylcarbonyl)naphtho[2,3-b]thiophene-4,9-dione;
• propan-2-yl 8-methoxy-4,9-dioxo-4,9-dihydronaphtho[2,3-b]thiophene-2-carboxylate;
• 2-benzoyl-8-methoxynaphtho[2,3-b]thiophene 4,9-dione;
• 8-hydroxy-2-(phenylacetyl)naphtho[2,3-b]thiophene-4,9-dione;
• 8-hydroxy-2-(4-methoxybenzoyl)naphtho[2,3-b]thiophene-4,9-dione;
• 2-(4-chlorobenzoyl)-8-hydroxynaphtho[2,3-b]thiophene-4,9-dione;
• 8-methoxy-2-(4-methoxybenzoyl)naphtho[2,3-b]thiophene-4,9-dione;
• 8-hydroxy-2-(3-phenylpropanoyl)naphtho[2,3-b]thiophene-4,9-dione;
• 8-methoxy-2-(phenylacetyl)naphtho[2,3-b]thiophene-4,9-dione;
• 8-methoxy-2-(3-phenylpropanoyl)naphtho[2,3-b]thiophene-4,9-dione;
• 8-hydroxy-2-(phenoxyacetyl)naphtho[2,3-b]thiophene-4,9-dione;
• 8-hydroxy-2-(pyridin-3-ylcarbonyl)naphtho[2,3-b]thiophene-4,9-dione;
• 2-(4-chlorobenzoyl)-8-methoxynaphtho[2,3-b]thiophene-4,9-dione;
• 4-methoxybenzyl 8-hydroxy-4,9-dioxo-4,9-dihydronaphtho[2,3-b]thiophene-2-carboxylate;
• 2-phenylethyl 8-hydroxy-4,9-dioxo-4,9-dihydronaphtho[2,3-b]thiophene-2-carboxylate;
• 8-methoxy-2-(phenoxyacetyl)naphtho[2,3-b]thiophene-4,9-dione;
• 8-methoxy-2-(pyridin-3-ylcarbonyl)naphtho[2,3-b]thiophene-4,9-dione;
• 4-methoxybenzyl 8-methoxy-4,9-dioxo-4,9-dihydronaphtho[2,3-b]thiophene-2-carboxylate;
• 8-hydroxy-2-(2-hydroxy-4-methoxybenzoyl)naphtho[2,3-b]thiophene-4,9-dione;
• 2-phenylethyl 8-methoxy-4,9-dioxo-4,9-dihydronaphtho[2,3-b]thiophene-2-carboxylate;
• and
• 2-(2-hydroxy-4-methoxybenzoyl)-8-methoxynaphtho[2,3-b]thiophene-4,9-dione.