Antitumor agent and bromodomain inhibitor

A method for treating disease associated with a bromodomain comprising administering a therapeutically effective amount of a compound represented by the formula [1] or a salt thereof:

• wherein R1 represents a hydrogen atom or an optionally substituted C1-6 alkyl group;
• R2 represents a hydrogen atom, a halogen atom, or an optionally substituted C1-6 alkyl group;
• R3 represents a halogen atom, an optionally substituted C1-6 alkyl group, an optionally substituted C2-6 alkenyl group, an optionally substituted C3-8 cycloalkyl group, an optionally substituted C4-8 cycloalkenyl group, an optionally substituted aryl group, an optionally substituted C1-6 alkoxy group, an optionally substituted C1-6 alkylamino group, an optionally substituted di(C1-6 alkyl)amino group, or an optionally substituted heterocyclic group;
• Z1, Z2 and Z3, which are the same or different, each represent a nitrogen atom or a group represented by the formula CR5 (wherein R5 represents a hydrogen atom, a halogen atom or an optionally substituted C1-6 alkyl group);
• X1 represents
• (1) a group represented by the formula C(═O)N(R6) (wherein the carbon atom binds to Ring A, and R6 represents a hydrogen atom, an amino-protecting group, or an optionally substituted C1-6 alkyl group,
• (2) a group represented by the formula N(R7)C(═O) (wherein the nitrogen atom binds to Ring A, and R7 represents a hydrogen atom, an amino-protecting group, or an optionally substituted C1-6 alkyl group;
• or R7 represents, together with one substituent R4 of Ring A, an optionally substituted C2-4 alkylene group, a group represented by the formula O—Y1 (wherein the oxygen atom binds to Ring A, and Y1 represents an optionally substituted C1-3 alkylene group), a group represented by the formula S(O)n—Y2 (wherein the sulfur atom binds to Ring A, Y2 represents an optionally substituted C1-3 alkylene group, and n represents an integer from 0 to 2), or a group represented by the formula N(R8)—Y3 (wherein the nitrogen atom binds to Ring A, Y3 represents an optionally substituted C1-3 alkylene group, and R8 represents a hydrogen atom, an amino-protecting group, an optionally substituted C1-6 alkyl group, or an optionally substituted aryl group)),
• (3) an optionally substituted divalent cyclic hydrocarbon group that is formed by removing each one hydrogen atom on the two adjacent atoms, or
• (4) an optionally substituted divalent heterocyclic group that is formed by removing each one hydrogen atom on the two adjacent atoms;
• Ring A represents a cyclic hydrocarbon group or a heterocyclic group;
• an m number of R4, which are the same or different, each represent a halogen atom, a cyano group, a nitro group, an amino-protecting group, an optionally substituted C1-6 alkyl group, an optionally substituted C2-6 alkenyl group, an optionally substituted C2-6 alkynyl group, an optionally substituted C3-8 cycloalkyl group, an optionally substituted C4-8 cycloalkenyl group, an optionally substituted aryl group, an optionally substituted C1-6 alkoxy group, an optionally substituted aryloxy group, an optionally substituted C1-6 alkylamino group, an optionally substituted di(C1-6 alkyl)amino group, an optionally substituted arylamino group, an optionally substituted carbamoyl group, an optionally substituted sulfamoyl group, an optionally substituted C1-6 alkylthio group, an optionally substituted arylthio group, an optionally substituted C1-6 alkylsulfonyl group, an optionally substituted arylsulfonyl group, an optionally substituted heterocyclic group, an optionally protected amino group, an optionally protected hydroxyl group, an optionally protected carboxyl group,
• an optionally substituted C2-5 alkylene group formed together by the two adjacent R4,
• an optionally substituted C2-4 alkylene group formed by one R4 together with R7,
• a group represented by the formula O—Y1 (wherein the oxygen atom binds to Ring A, and Y1 represents an optionally substituted C1-3 alkylene group), which is formed by one R4 together with R7,
• a group represented by the formula S(O)n—Y2 (wherein the sulfur atom binds to Ring A, Y2 represents an optionally substituted C1-3 alkylene group, and n represents an integer from 0 to 2), which is formed by one R4 together with R7, or
• a group represented by the formula N(R8)—Y3 (wherein the nitrogen atom binds to Ring A,
• Y3 represents an optionally substituted C1-3 alkylene group, and R8 represents a hydrogen atom, an amino-protecting group, an optionally substituted C1-6 alkyl group, or an optionally substituted aryl group), which is formed by one R4 together with R7;
• and
• m represents an integer from 0 to 5.