hetacillin hetacillin hetacillin is a beta-lactam antibiotic that is part of the aminopenicillin family. it is a prodrug and has no antibacterial activity itself, but quickly splits off acetone in the human body to form ampicillin, which is active against a variety of bacteria. hetacillinclinical datatrade nameshetacin, versapenahfs/drugs.comveterinary useroutes ofadministrationintramammary injectionatc codej01ca18 (who) legal statuslegal status us: ℞-only identifiers iupac name (2s,5r,6r)-6--3,3-dimethyl-7-oxo-4-thia-1-azabicycloheptane-2-carboxylic acid cas number3511-16-8 ypubchem cid443387drugbankdb00739 ychemspider391616 nuniitn4jsc48cvkeggd01074 nchemblchembl1201116 ncomptox dashboard (epa)dtxsid4023121 echa infocard100.020.466 chemical and physical dataformulac19h23n3o4smolar mass389.47 g·mol−13d model (jsmol)interactive image smiles cc1((n2(s1)(c2=o)n3c(=o)(nc3(c)c)c4ccccc4)c(=o)o)c inchi inchi=1s/c19h23n3o4s/c1-18(2)13(17(25)26)21-15(24)12(16(21)27-18)22-14(23)11(20-19(22,3)4)10-8-6-5-7-9-10/h5-9,11-13,16,20h,1-4h3,(h,25,26)/t11-,12-,13+,16-/m1/s1 nkey:dxvuyoaedjxbpy-nffdbfgfsa-n n ny (what is this?) (verify) administration hetacillin can be administered orally. the potassium salt, hetacillin potassium, is administered by injection, either intravenously or intramuscularly. it is sold under the trade name hetacin for intramammary injection in veterinary use. hetacillin was withdrawn from the market for human use when the discovery was made that it had no advantages over ampicillin. chemistry hetacillin is prepared from ampicillin and acetone. in aqueous solutions it is unstable, with a half life of 15 to 30 minutes at 37 °c (99 °f) and ph 7, quickly releasing acetone again. as opposed to ampicillin, hetacillin is only marginally broken down by the bacterial enzyme beta-lactamase, at least in vitro.