Novel azetidine derivatives of the formula ##STR1## wherein R.sub.1 is an acylamido group, R.sub.2 is selected from the group consisting of ##STR2## wherein R.sub.4, R.sub.5 and R.sub.6 are individually selected from the group consisting of hydrogen, lower alkyl and lower alkenyl, n is 2 or 3 and -- in the case when formula IIB is a phenyl -- this group may carry 1 to 4 substituents selected from the group consisting of halogen, lower alkyl, lower alkenyl and phenyl, and R.sub.3 is lower alkyl optionally substituted with 1 or 2 phenyls which phenyl groups may be substituted with nitro and a process for their preparation and process for the preparation of cephalosporanic acid derivatives using the azetidines of formula I as intermediates. This is a division of Serial No. 547,948, filed Feb. 7, 1975 now Pat. No. 4,007,202.
公式为##
STR1##的新型
氮杂
丁烷衍
生物,其中R.sub.1为
酰胺基团,R.sub.2选自以下组合:##
STR2##其中R.sub.4,R.sub.5和R.sub.6分别选自
氢,低烷基和低
烯基组,n为2或3,当公式IIB为
苯时,该基团可以携带1至4个取代基,所选取代基来自卤素,低烷基,低
烯基和
苯基,R.sub.3为低烷基,可选择地取代1或2个
苯基,其中
苯基可以被硝基取代,以及使用公式I的
氮杂
丁烷中间体制备
头孢菌素酸衍
生物的过程。本申请为1975年2月7日提交的申请号547,948的分案,现已授权专利号为4,007,202。