申请人:Ciba-Geigy Corporation
公开号:US04614614A1
公开(公告)日:1986-09-30
The present invention relates to an improved process for the manufacture of (3S)-3,4-trans-disubstituted azetidinones of the formula ##STR1## in which R.sub.1 represents hydrogen or lower alkyl, R.sub.2 represents hydrogen or a hydroxy-protecting group, Y represents the group --S(.dbd.O)--R.sub.3 or --S(.dbd.O).sub.2 --R.sub.3 wherein R.sub.3 represents an organic radical bonded to the sulphur atom by a carbon atom that is not bonded to hydrogen, or the group --C(.dbd.O)--O--R.sub.3 ' wherein R.sub.3 ' represents an organic radical bonded to the oxygen atom of the carboxy group by a carbon atom that is not bonded to hydrogen, or a carboxy-protecting group, and R.sub.4 represents hydrogen or an amino-protecting group R.sub.4 '. The process according to the invention is carried out under particularly favorable reaction conditions and yields compounds (I) in particularly high yields.
本发明涉及一种改进的制备(3S)-3,4-顺式二取代氮杂环酮的方法,其化学式为##STR1##其中R.sub.1代表氢或较低的烷基,R.sub.2代表氢或羟基保护基,Y代表--S(.dbd.O)--R.sub.3或--S(.dbd.O).sub.2--R.sub.3,其中R.sub.3表示通过碳原子与硫原子结合而不与氢原子结合的有机基团,或--C(.dbd.O)--O--R.sub.3',其中R.sub.3'表示通过碳原子与羧基氧原子结合而不与氢原子结合的有机基团,或羧基保护基,R.sub.4代表氢或氨基保护基R.sub.4'。根据本发明的方法在特别有利的反应条件下进行,产率特别高,得到化合物(I)。