Wiktionary
hetacillin
n. A beta-lactam that is converted by the body to ampicillin.
Wikipedia
Hetacillin
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.