Hetacillin is a b-lactam antibiotic that is part of the aminopenicillin family. It is a prodrug and it has no antibacterial activity but quickly release acetone in the human body to form ampicillin.
Hetacillin is used in the treatment of bacterial infections caused by
susceptible, usually gram-positive, organisms. It has been withdrawn from
the market since it has been discovered that it has no therapeutic advantage
compared to ampicillin.
Dosage and Administration
Hetacillin can be administered orally. The potassium salt, hetacillin potassium, is administered by injection, either intravenously or intramuscularly
Mechanism of Action
Hetacillin is hydrolysed to ampicillin that binds to the penicillin binding proteins found in susceptible bacteria.
Other pharmacological effects
CAS number: 3511-16-8 EINECS: 222-512-5
Molecular Formula: C19H23N3O4S
Average mass: 389.469 Da
Monoisotopic mass: 389.140930 Da
Systematic name: (2S,5R,6R)-6-[(4R)-2,2-Dimethyl-5-oxo-4-phenyl-1-imidazolidinyl]-3,3-dimethyl-7-oxo-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylic acid
SMILES: (2S,5R,6R)-6-[(4R)-2,2-Dimethyl-5-oxo-4-phenyl-1-imidazolidinyl]-3,3-dimethyl-7-oxo-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylic acid
Std. 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
Appearance: Rectangular plates from water + methyl isobutyl ketone, dec. 182.8-183.9°C; also reported as mp 189.2-191.0°C.
Melting point: 190°C
Optical rotation: +366° (pyridine).
Solubility: Practically insoluble in most organic solvents and water; soluble in diluted aqueous NaOH solution (pH 7-8), DMF, DMSO, pyridine, methanol (with decomposition).
Synthesis: Hetacillin is prepared from ampicillin and acetone. In aqueous solutions it ihas a half life of 15 to 30 minutes at 37 °C and pH=7, quickly releasing acetone .
1. Sutherland, R., Robinson, O. P. "Laboratory and pharmacological studies in man with hetacillin and ampicillin". British Medical Journal 2, 804–808, (1967).
2. Faine, S., Harper, M. "Independent antibiotic actions of hetacillin and ampicillin revealed by fast methods". Antimicrobial agents and chemotherapy 3, 15–18, (1973).
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