A Total Synthesis of (1R,5R)-3-Phenylmethyl-4-thia-2,6-diazabicyclo [3.2.0]hept-2-en-7-one, a Useful Intermediate for the Preparation of Penem and Cepham Derivatives
The preparation of the thiazoline (1R,5R)-3-phenylmethyl-4-thia-2,6-diazabicyclo [3.2.0]hept-2-en-7-one (1) is presented. This compound, which has been extensively used as an intermediate for the synthesis of penems and cephams, has been obtained starting from a C-4 unsubstituted azetidinone by means of facile processes while chirality has been obtained through enzymatic resolution.