title: Transformations of penicillins: new methods of formation and reactions of 6,6-disubstituted penams and 7,7-disubstituted cephems.
mesh_terms: D002511:Cephalosporins; D055598:Chemical Phenomena; D002621:Chemistry; D010406:Penicillins; D013329:Structure-Activity Relationship
chemical_list: D002511:Cephalosporins; D010406:Penicillins