申请人:Orchid Chemicals and Pharmaceuticals Limited
公开号:US20030232983A1
公开(公告)日:2003-12-18
The present invention relates to a process for preparing 2&agr;-methyl-2&bgr;-substituted methyl penam derivatives from cepham derivatives, more particularly the present invention provides a novel process for preparing 2&bgr;-heterocyclyl methyl penam derivatives of the formula (I)
1
wherein R
1
represents carboxylic acid protecting group; R
2
and R
3
may be same or different and independently represent hydrogen, halogen, NH
2
, acylamino, phthalimido with a proviso that both R
2
and R
3
are not NH
2
, acylamino, phthalimido; Het represents a 5 or 6 membered nitrogen containing heterocycle ring system having one or more heteroatoms selected from O, S, or N.
该发明涉及一种从头孢衍生物制备2&agr;-甲基-2&bgr;-取代甲基佩纳姆衍生物的过程,更具体地,该发明提供了一种制备式(I)1的2&bgr;-杂环甲基佩纳姆衍生物的新方法,其中R1代表羧酸保护基;R2和R3可以相同也可以不同,并且独立地代表氢、卤素、NH2、酰胺基、邻苯二甲酰亚胺,但R2和R3不能同时为NH2、酰胺基、邻苯二甲酰亚胺;Het代表具有来自O、S或N的一个或多个杂原子的5或6元素含氮杂环环系统。