beta-Lactams [Chemical/Ingredient] Penicillins [Chemical/Ingredient] Penicillins M0016152 Penicillins D010406 N0000011281 A group of antibiotics that contain 6-aminopenicillanic acid with a side chain attached to the 6-amino group. The penicillin nucleus is the chief structural requirement for biological activity. The side-chain structure determines many of the antibacterial and pharmacological characteristics. (Goodman and Gilman's The Pharmacological Basis of Therapeutics, 8th ed, p1065) C0030842 C291637 Antibiotics, Penicillin 7986