Somoza et al., Synthesis of Optically Active (Pivaloyloxy) Methyl 2', 3'-Substituted 4'-Oxoazetidin-1'-YL-3-Methylbut-2-Enoates from 6-APA, Tetrahedron, (1988), vol. 44, No. 23, pp. 7007-7012. |
Martel et al., Nuclear analogs of .beta.-lactam antibiotics, XVII,.sup.1 Stereospecific synthesis of penem and carbapenem precursors, Can. J. Chem., (1983), vol. 61, pp. 1899-1901. |
Wolfe et al., Sulfur-free Penicillin Derivatives.II.Functionalization of the Methyl Groups, Can. J. Chem., (1972), vol. 50, pp. 2898-2901. |
Wolfe et al., Sulfur-free Penicillin Derivatives.III.Regeneration of Fused .beta.-Lactams via Intramolecular Displacement, Can. J. Chem., (1972), vol. 50, pp. 2902-2905. |
Sheehan et al., Removal and Displacement of the Thiazolidine Ring in Penicillin. II..sup.1 Selective Carbon-Sulfur Bond Cleavage, Jour. Am. Chem. Soc., (1973), vol. 95, No. 9, pp. 3064-3065. |
Kukolja, Electrophilic Opening of the Thiazolidine Ring in Penicillins, Jour. Am. Chem. Soc., (1971), vol. 93, No. 23, pp. 6267-6269. |
Kukolja, A Stereoselective Synthesis of 6-Phthalimido-5-epipenicillanates, Jour. Am. Chem. Soc., (1971), vol. 93, No. 23, pp. 6269-6270. |