申请人:Sankyo Company Limited
公开号:EP0839812A1
公开(公告)日:1998-05-06
A process for preparing a compound of formula (Ia):
[in which R1, R2 and R5 are each hydrogen or alkyl; R3 and R4 are each hydrogen, alkyl, formyl, alkylcarbonyl, arylcarbonyl, carboxy, alkoxycarbonyl, aryloxycarbonyl, hydroxy, alkylcarbonyloxy, formyloxy, arylcarbonyloxy, optionally substituted alkoxy or halogen; W is methylene, carbonyl or a group of formula >C=N-OV, in which V is hydrogen, alkylcarbonyl, arylcarbonyl or optionally substituted alkyl; and n is an integer of from 1 to 3] or a salt thereof by reduction of a compound of formula (I):
or a salt thereof, in which R1 to R5, W and n are as defined above.
一种制备式 (Ia) 化合物的工艺:
[其中 R1、R2 和 R5 分别为氢或烷基;R3 和 R4 分别为氢、烷基、甲酰基、烷基羰基、芳基羰基、羧基、烷氧基羰基、芳氧基羰基、羟基、烷基羰氧基、甲酰基氧基、芳基羰氧基、任选取代的烷氧基或卤素;W 是亚甲基、羰基或式 >C=N-OV 的基团,其中 V 是氢、烷基羰基、芳基羰基或任选取代的烷基;以及 n 是 1 至 3 的整数]或通过还原式(I)化合物而得到的盐:
或其盐,其中 R1 至 R5、W 和 n 如上文所定义。