Wiktionary
talbutal
n. 5-allyl-5-sec-butylbarbituric acid, a barbiturate that is a structural isomer of butalbital.
Wikipedia
Talbutal
Talbutal (Lotusate) is a barbiturate with a short to intermediate duration of action. It is a structural isomer of butalbital. Talbutal is a schedule III drug in the U.S.