Cdk inhibitors having 3-hydroxychromen-4-one structure

A compound represented by the following formula (1):

• 20
• in which
• A represents hydrogen or nitro, or represents amino which is optionally substituted by C1-C4-alkylcarbonyl or carbamoyl, or represents a structure selected from a group consisting of
• 21
• wherein R4 represents hydrogen or C1-C6-alkyl which is optionally substituted by amino or hydroxy, R3 represents C1-C6-alkyl which is optionally substituted by amino or hydroxy and D represents halogen,
• B represents methyl, or represents amino which is optionally mono- or disubstituted by substituents selected from a group consisting of C1-C6-alkyl, hydroxy-C1-C6-alkyl, C3-C6-cycloalkyl, acetyl, phenyl, benzyl and piperidinyl,
• X, Y and Z independently of one another represent hydrogen, hydroxy, nitro, cyano or halogen, or represent amino which is optionally substituted by C1-C4-alkyl, C1-C4-alkylcarbonyl or carbamoyl, or represent C1-C4-alkyl which is optionally substituted by hydroxy or halogen, pharmaceutically acceptable salt, hydrate, solvate or isomer thereof.