The invention relates to a process for preparing a compound of formula (I):
wherein R1 is a group represented by the formula:
wherein R2, R3, R4, R5, R6, R7 and R8 are each independently a hydrogen atom or a C1-6 alkyl,
or a salt thereof, which comprises reacting a compound of formula (II):
or a salt thereof, with an acylating agent; with thionyl chloride or oxalyl chloride and then with an alcohol; with an alkylating agent; or with an alcohol.
本发明涉及一种制备式 (I) 化合物的工艺:
其中 R1 是由式表示的基团:
其中 R2、R3、R4、R5、R6、R7 和 R8 各自独立地为氢原子或 C1-6 烷基、
或其盐,其中包括反应式 (II) 的化合物:
或其盐与酰化剂反应;与亚
硫酰氯或
草酰氯反应,然后与醇反应;与烷化剂反应;或与醇反应。