| abstract |
Procedure for the preparation of azetidine derivatives, with the general formula **formula** in which R1 represents a penicillin or cephalosporin amido group, R2 represents one of the groups of the following formulas **formulas** in which R4,R5 , and R6 are the same or different and each does not represent a hydrogen atom or a lower alkyl or alkenyl group, n represents 2 or 3 and when formula IIB represents a phenyl group, this group can carry from one to four substituents selected from the group formed by the halogen atoms and the lower alkyl, lower alkenyl and phenyl groups. |