| —— | 
                                        (4-methoxyphenyl)methyl (2S,5R,6R)-3-methylidene-4,7-dioxo-6-[(2-phenylacetyl)amino]-4λ4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylate | 
                                        139391-03-0 | 
                                        C23H22N2O6S | 
                                        454.503 | 
                                    
                                                                                                                                            
                                        | —— | 
                                        diphenylmethyl (3R,5R,6R)-2-methylene-6-(phenylacetamido)penam-3-carboxylate | 
                                        139371-97-4 | 
                                        C28H24N2O4S | 
                                        484.576 | 
                                    
                                                                                                                                            
                                        | —— | 
                                        Benzhydryl (R)-2-((1R,5R)-3-Benzyl-7-oxo-4-thia-2,6-diazabicyclo[3.2.0]hept-2-en-6-yl)-3-methylbut-3-enoate | 
                                        119944-09-1 | 
                                        C29H26N2O3S | 
                                        482.603 | 
                                    
                                                                                                                                            
                                        | —— | 
                                        (E)-2-((1R,5R)-3-Benzyl-7-oxo-4-thia-2,6-diaza-bicyclo[3.2.0]hept-2-en-6-yl)-3-trifluoromethanesulfonyloxy-but-2-enoic acid benzhydryl ester | 
                                        139371-95-2 | 
                                        C29H23F3N2O6S2 | 
                                        616.639 | 
                                    
                                                                                                                                            
                                        | —— | 
                                        (E)-2-((1R,5R)-3-Benzyl-7-oxo-4-thia-2,6-diaza-bicyclo[3.2.0]hept-2-en-6-yl)-3-hydroxy-but-2-enoic acid benzhydryl ester | 
                                        133696-58-9 | 
                                        C28H24N2O4S | 
                                        484.576 |