Debutyldronedarone-d 7 hydrochloride is deuterated labeled Debutyldronedarone hydrochloride. Debutyldronedarone (SR35021) hydrochloride, the main metabolite of Dronedarone, is a selective thyroid hormone receptor α 1 ( TRα 1 ) inhibitor. Debutyldronedarone hydrochloride inhibits T3 binding to TRα 1 and TRβ 1 by 77% and 25%, respectively. Debutyldronedarone hydrochloride can be used for the research of arrhythmic.