Synthetic routes to azetidinones related to nocardicin

摘要

There is disclosed a process for the manufacture of azetidinones related to nocardicin having the formula <IMAGE> (I) wherein R is a saturated or unsaturated alkyl having from 1 to 6 carbon atoms, alpha -aminobenzyl, benzyl, free or substituted phenyl, or a free or substituted heterocyclic; R1 is hydrogen, alkyl having from 1 to 4 carbon atoms, trimethylsilyl, trichloroethyl, benzhydryl or benzyl; and R2 is a free or substituted phenyl, or a free or substituted heterocyclic, using the same starting compound, but with the possibility of proceeding to the final compound via two somewhat different routes. A number of novel intermediates are also disclosed.