The invention relates to compounds of the general formula (X) ##STR1## wherein R is as a removable protecting substituent of the amido group a phenyl group or a benzyl group substituted by one or more alkoxy group(s) having 1-4 carbon atoms and R.sup.1 stands for a hydrogen atom or an alkyl group having 1-4 carbon atoms and a process for the preparation thereof. The compounds of the general formula (X) can be prepared from the starting materials of the general formula (V), wherein R and R.sup.1 are as stated above and Z is an alkyl group having 1-4 carbon atoms. The compounds of the general formula (X) are useful pharmaceutical intermediates which can be used in the preparation of known antibiotics (e.g. Thienamycin and PS-5).
该发明涉及一般式(X)的化合物 ##STR1## 其中R是
氨基团的可去保护取代基,为苯基或苄基,其上取代有一个或多个含有1-4个碳原子的烷氧基,R.sup.1代表氢原子或含有1-4个碳原子的烷基,以及其制备方法。一般式(X)的化合物可从一般式(V)的起始原料制备而得,其中R和R.sup.1如上所述,Z是含有1-4个碳原子的烷基。一般式(X)的化合物是有用的药物中间体,可用于制备已知的抗生素(例如Thienamycin和PS-5)。