Studies on Coumarins of a Chinese Drug “Qian-Hu”; VI¹, Coumarins of Angelica edulis

Abstract

Coumarins, edulisin I (Ae-I) (1) and edulisin II (Ae-VI) (6), were isolated from ether extracts of the roots and rhizomes of Angelica edulis Miyabe (Umbelliferae), together with five known coumarins. The structures of edulisin I (1) and edulisin II (6) were established to be 2′ (S), 3′ (R)-3′-senesioyloxy-O-trans-p-coumaroyl-2′, 3′-dihydrooroselol and 2′ (S), 3′ (R)-senecioyloxy-O- senecioyl-2′, 3′-dihydro-oroselol by chemical studies and spectral analysis. Ae-III (3) was identified with isopeucenidin and the configuration at C-2′ and C-3′ of Ae-III (3) was assigned as R and R, respectively by chemical studies and an X-ray crystallographic analysis. Accordingly, the optical rotation of isopeucenidin reported by Steck and Wetter has been corrected.