FIELD: chemistry.SUBSTANCE: invention relates to a compound represented by general formula (I) or a pharmaceutically acceptable salt thereof, wherein A1 is a group selected from the group consisting of the following items a) to c), where a) C6 aryl, where the ring is unsubstituted or substituted with 1 or 2 substituents independently selected from the group comprising a halogen atom, hydroxy, C1-6 alkyl, C1-6 alkoxy, halogen-C1-6 alkyl, C1-6 alkoxycarbonyl, cyano, hydroxy-C1-6 alkyl, carbamoyl, nitro, amino, C1-6 alkoxycarbonylamino-C1-6 alkyl, mono(di)C1-6 alkylamino, (C1-6 alkyl)carbonylamino, C1-6 alkylsulphonylamino and C1-6 alkylsulphonyl； b) thiazolyl, and c) a group selected from the group consisting of pyridyl, pyrimidinyl, pyrazinyl and pyridazinyl, where the ring is unsubstituted or substituted with 1 or 2 substituents independently selected from the group comprising a halogen atom, hydroxy, C1-6 alkyl, C1-6 alkoxy, halogen-C1-6 alkyl, cyano and halogen-C1-6 alkoxy； A2 is a group selected from the group including the following items d) to f), where d) C6-10 aryl, in which the ring is unsubstituted or substituted with 1 or 2 substituents independently selected from the group including: halogen atom, hydroxy, C1-6 alkyl, C1-6 alkoxy, hydroxy-C1-6 alkoxy, halogen-C1-6 alkyl, halogen-C1-6 alkoxy, cyano, amino, nitro, carboxy, (C1-6 alkyl)carbonylamino, (C1-6 alkyl) carbonyloxy, (C1-6 alkyl)carbonyl and (C7-10 aralkyloxy)carbonyl； e) a group consisting of thienyl, pyrrolyl, pyrazolyl, imidazolyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyl, pyranyl, pyridyl, 1-oxidopyridyl, pyridazinyl, pyrimidinyl, pyrazinyl, furazanyl, morphonyl, benzothiazolyl, isoquinolyl, quinolyl, 2,3-dihydrobenzofuranyl, imidazo[1,2-a]pyridyl, imidazo[1,2-a]pyrazinyl, benzo[1,3]dioxolyl, benzothienyl, 5,6,7,8-tetrahydroimidazo[1,2- a]pyrazinyl, where the ring is unsubstituted or substituted with 1 or 2 substituents independently selected from the group comprising a halogen atom, hydrox
