| abstract |
(57) [Summary] Formula (I) Wherein X 1 is a bond or —O (CH 2 ) m — (m is an integer 1, 2 or 3), X 2 is a bond, — (CH 2 ) n —, etc. (n is an integer 1, 2 or 3 ), R 1 is hydrogen or amino protecting group, R 2 is hydroxy (lower) alkyl or (lower) alkoxy (lower) alkyl, A is phenyl, pyridyl, indolyl or carbazolyl, each of which is halogen, hydroxy, lower alkyl, etc. B may be substituted with one or two substituents selected from the group consisting of: phenyl or pyridyl, each of which is one or two selected from the group consisting of halogen, hydroxy, nitro, and the like. Each of which may be substituted. Or a pharmaceutically acceptable salt thereof, which is useful as a medicament. |