6-aminopenicillanic acid

6-aminopenicillanic acid is a small molecule β-lactam containing organic acid that serves as the **core chemical structure of all penicillin antibiotics**. It consists of a fused β-lactam-thiazolidine ring system with an amino group at position 6. Industrially, it is derived from penicillin G through enzymatic cleavage (penicillin acylases), providing the nucleus for generating semisynthetic penicillins (such as ampicillin, amoxicillin, oxacillin, carbenicillin, etc.) by substitution at the 6-amino position[1][3][7][12]. **Mechanism of action:** 6-aminopenicillanic acid itself retains the basic β-lactam mechanism—*it inhibits bacterial cell wall biosynthesis by binding and inactivating DD-transpeptidase enzymes (penicillin-binding proteins, PBPs), blocking cross-linking of peptidoglycan, leading to cell lysis and death*. However, by itself, 6-APA's antimicrobial spectrum is limited and it is primarily used as a pharmaceutical intermediate, not a finished drug[3][7][8]. Its chemical similarity to the D-Ala-D-Ala terminus of the cell wall precursors confers its mode of binding[8].

Other names

aminopenicillanic acidpeninpenicinamoxicillin related compound Aflucloxacillin EP impurity C6-amino-penicillanic acid(2S,5R,6R)-6-amino-3,3-dimethyl-7-oxo-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylic acidamoxicillin related compound A (15 mg)phenacyl 6-aminopenicillinatephenacyl6-aminopenicillinatephenacyl-6-aminopenicillinate6-aminopenicillamine acid6-aminopenicillanateamino penicillanic acid6-aminopenicin llanic acid(2s,5r,6r)-(+)-6-amino-3,3-dimethyl-7-oxo-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylic acid(2s,5r,6r)-6-amino-3,3-dimethyl-7-oxo-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylicacid4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylic acid, 6-amino-3,3-dimethyl-7-oxo-, (2s,6r)-6beta-aminopenicillanic acid