BIOACTIVE CONSTITUENTS OF CHINESE NATURAL MEDICINES .1. NEW SESQUITERPENE KETONES WITH VASORELAXANT EFFECT FROM CHINESE MOXA, THE PROCESSEDLEAVES OF ARTEMISIA-ARGYI LEVL ET VANT - MOXARTENONE AND MOXARTENOLIDE

Two new sesquiterpene ketones, moxartenone and moxartenolide, and thre e octadecadienoic acids were isolated from Chinese moxa, the processed leaves of Artemisia argyi LEVL. et VANT., together with two sesquiter penes, five triterpenes, two phenyl propanoids and three polyoxyflavon es. The chemical structures of new sesquiterpenes, moxartenone, moxart enolide, and octadecadienoic acids were determined on the basis of che mical and physicochemical evidence. Moxartenolide was found to inhibit the contractions induced by a high concentration of K+, by norepineph rine, and by serotonin in isolated aortic strips of rat, while moxarte none showed little activity.