title: Electronic structures of cephalosporins and penicillins. 2. Disulfide and beta-lactam chromophores. Structure-activity relationships.
mesh_terms: D002511:Cephalosporins; D055598:Chemical Phenomena; D002621:Chemistry; D002942:Circular Dichroism; D004220:Disulfides; D010406:Penicillins; D011789:Quantum Theory; D013056:Spectrophotometry, Ultraviolet; D013329:Structure-Activity Relationship; D047090:beta-Lactams
chemical_list: D002511:Cephalosporins; D004220:Disulfides; D010406:Penicillins; D047090:beta-Lactams