A process for the preparation of a compound of formula (I) or a salt thereof:
wherein R' is an optionally substituted aryl group and R2 is hydrogen, a salting ion or a sulphonyl ester forming group; characterised in that a mono-deprotonated methylene compound of the formula (II):
wherein R1 and R2 are as defined with respect to formula (I) and wherein any reactive groups may be protected, is reacted with carbon dioxide.
一种制备式(I)化合物或其盐的工艺:其中 R'为任选取代的芳基,R2 为氢、盐离子或形成
磺酸酯的基团;其特征在于,将式(II)的
单质子化亚甲基化合物(其中 R1 和 R2 如式(I)所定义)与
二氧化碳反应,其中任何反应基团均可被保护。