The synthesis of some new 3-carbomethoxy-5-oxoperhydro-1, 4-thiazepines is described. Halogenation studies led to the preparation of three potential substituted penam ring precursors: 6, 7-dibromo-3-carbomethoxy-5-oxoperhydro-1, 4-thiazepine, 3-carbomethoxy- 6, 7-dichloro-5-oxoperhydro-1, 4-thiazepine, and 3-carbomethoxy-7-chloro-6, 6-dimethyl-5- oxoperhydro-1, 4-thiazepine. Preliminary studies on the reactivity of these α- ...
