penamecillin penamecillin penamecillin, an acetoxymethyl ester of benzylpenicillin, is a prodrug processed to benzylpenicillin by esterases. penamecillinclinical dataahfs/drugs.cominternational drug namesatc codej01ce06 (who) identifiers iupac name (acetyloxy)methyl (2s,5r,6r)-3,3-dimethyl-7-oxo-6--4-thia-1-azabicycloheptane-2-carboxylate cas number983-85-7 ypubchem cid13795chemspider8426255 nuniih0p1ye5581keggd05406 ychebichebi:131733 ncomptox dashboard (epa)dtxsid10243547 echa infocard100.012.338 chemical and physical dataformulac19h22n2o6smolar mass406.45 g·mol−13d model (jsmol)interactive image smiles cc(=o)ococ(=o)1c(s2n1c(=o)2nc(=o)cc3=cc=cc=c3)(c)c inchi inchi=1s/c19h22n2o6s/c1-11(22)26-10-27-18(25)15-19(2,3)28-17-14(16(24)21(15)17)20-13(23)9-12-7-5-4-6-8-12/h4-8,14-15,17h,9-10h2,1-3h3,(h,20,23)/t14-,15+,17-/m1/s1 nkey:nloomwltuvbwaw-hllboeozsa-n n ny (what is this?) (verify)