From the herb Stephania delavayi Diels (Menispermaceae) grown in Transcaucasia, by chromatography on alumina we have isolated a new base (I) with the composition C20H21O6N, mp 221-222°C (from methanol, Kofler), [α]D -180° (c 1.55; chloroform) for which the structure of 16-oxodelavayine is proposed.