1. a Studies on Lactams. Part XLIII. For Part XLII see A. K. Bose, M. S. Manhas, H. P. S. Chawla, and B. Dayal J. Chem. Soc., Perkin 1, 1880 (1975).
2. b Presented in part at the Fourth International Congress of Heterocyclic Chemistry, Salt Lake City, Utah, June, 1973.
3. c E. H.Flynn, Ed., “Cephalosporins and Penicillins: Chemistry and Biology”, Adacemic Press, New York, 1972.