Thiazole derivative

A thiazole derivative represented by the formula (I)

• or a pharmaceutically acceptable salt thereof,
• wherein:
• X1 and X2 are different from each other and represent a sulfur atom or a carbon atom;
• R1 is selected from the group consisting of benzothiazolyl, benzoxazolyl or benzo(1,3)dioxoly;
• R2 represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkyl group having 1 to 6 carbon atoms substituted with 1 to 5 halogen atoms, an alkoxy group having 1 to 6 carbon atoms, an alkanoyl group having 1 to 6 carbon atoms, or a hydroxyalkyl group having 1 to 5 carbon atoms;
• and A represents a group which is represented by the formula
• wherein:
• represents the bond to the thiazole group of formula (I);
• R3 represents a hydrogen atom;
• a hydroxy group;
• an alkyl group having 1 to 6 carbon atoms;
• a phenylalkyl group having 7 to 12 carbon atoms;
• or
• a phenylalkyl group having 7 to 12 carbon atoms, substituted with a hydroxy group, an alkoxy group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms substituted with an alkoxy group having 1 to 6 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms substituted with an alkylamino group having 1 to 6 carbon atoms,
• R4 represents a phenyl group;
• a phenyl group substituted with 1 to 5 members selected from the group consisting of halogen atoms, alkyl groups having 1 to 6 carbon atoms, alkoxy groups having 1 to 6 carbon atoms, a carbamoyl group, and a cyano group;
• a hydrogen atom;
• an alkyl group having 1 to 12 carbon atoms;
• an alkenyl group having 2 to 12 carbon atoms;
• a cycloalkyl group having 3 to 7 carbon atoms;
• an alkyl group having 1 to 12 carbon atoms substituted with an alkoxy group having 1 to 6 carbon atoms, a hydroxy group, an alkoxyphenylalkoxy group having 8 to 12 carbon atoms, a phthalimidoyl group, a toluenesulfonyloxy group, or a morpholino group;
• an alkyl group having 1 to 6 carbon atoms substituted with 1 to 5 halogen atoms;
• a cycloalkyl group having 3 to 9 carbon atoms substituted with an oxo group;
• a tetrahydropyranyl group;
• a 4-piperidinyl group;
• a piperidinyl group substituted with an alkyl group having 1 to 6 carbon atoms or a t-butoxycarbonyl group;
• a cyclohexanespiro-2′-(1,3-dioxoranyl) group;
• a pyrrolidin-2-one-5-yl group;
• a group represented by the formula —Y1—Z1—NR5—Z2—Y2—R6,
• wherein:
• Y1 and Y2 are the same or different from each other and represent a single bond or an alkylene group having 1 to 12 carbon atoms;
• R5 represents a hydrogen atom or an alkyl group having 1 to 12 carbon atoms;
• Z1 and Z2 are the same or different from each other and represent a single bond;
• an alkylene group having 1 to 7 carbon atoms;
• —CO—;
• —CO2—
• —SO2—;
• or
• —OCO—, and
• R6 represents
• a cycloalkyl group having 3 to 7 carbon atoms;
• an alkyl group having 1 to 6 carbon atoms substituted with 1 to 3 halogen atoms;
• an alkenyl group having 2 to 6 carbon atoms;
• an alkynyl group having 2 to 6 carbon atoms;
• an amino group;
• an amino group substituted with 1 to 2 groups selected from the group consisting of an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 7 carbon atoms, and a t-butoxycarbonyl group;
• a piperidino group;
• a piperidinyl group;
• a piperidinyl group substituted with an alkyl group having 1 to 6 carbon atoms;
• a pyrrolidinyl group;
• a piperazinyl group;
• a piperazinyl group substituted with an alkyl group having 1 to 6 carbon atoms;
• a morpholino group;
• a hydroxy group;
• an alkoxy group having 1 to 6 carbon atoms;
• an alkoxy group having 1 to 6 carbon atoms substituted by a hydroxy group or an alkoxy group having 1 to 6 carbon atoms;
• an oxetan-2-yl group;
• a tetrahydrofuranyl group;
• a tetrahydropyranyl group;
• a hydrogen atom;
• a phenyl group;
• a phenyl group substituted with an alkoxy group having 1 to 4 carbon atoms;
• or
• a group that forms a ring when linked to the nitrogen atom of the above formula;
• or
• a group represented by the formula —Y3—CO—R41,
• wherein:
• Y3 represents a single bond or an alkylene group having 1 to 7 carbon atoms,
• R41 represents
• a hydroxy group;
• an alkoxy group having 1 to 6 carbon atoms;
• a piperidino group;
• a piperazin-1-yl group substituted by an alkyl group having 1 to 6 carbon atoms, a morpholinoalkyl group having 5 to 10 carbon atoms, or an alkylaminoalkyl group having 2 to 14 carbon atoms;
• or
• a morpholino group.