Hetacillin

Hetacillin

Clinical data
Trade names	Hetacin
AHFS/Drugs.com	Veterinary Use
Routes of administration	Intramammary injection
ATC code	J01CA18 (WHO)
Legal status
Legal status	US: ℞-only
Identifiers
IUPAC name (2S,5R,6R)-6-[(4R)-2,2-dimethyl-5-oxo-4-phenylimidazolidin-1-yl]-3,3-dimethyl-7-oxo-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylic acid
CAS Number	3511-16-8 Y
PubChem CID	443387
DrugBank	DB00739 Y
ChemSpider	391616 N
UNII	TN4JSC48CV
KEGG	D01074 N
ChEMBL	CHEMBL1201116 N
ECHA InfoCard	100.020.466
Chemical and physical data
Formula	C19H23N3O4S
Molar mass	389.469 g/mol
3D model (JSmol)	Interactive image
SMILES CC1([C@@H](N2[C@H](S1)[C@@H](C2=O)N3C(=O)[C@H](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 N Key:DXVUYOAEDJXBPY-NFFDBFGFSA-N N
NY (what is this?)

Hetacillin is a beta-lactam antibiotic that is part of the aminopenicillin family. It is a prodrug and it has no antibacterial activity itself, but quickly splits of acetone in the human body to form ampicillin, which is active against a variety of bacteria.

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 removed from the market for human use when the discovery was made that it is actually cleaved in the gastrointestinal tract to formaldehyde and had no advantages over ampicillin.

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.