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Hyperdioxane A, a Conjugate of Dibenzo-1,4-dioxane and Sesquiterpene from Hypericum ascyron
Kanji Niwa1, Naonobu Tanaka1,2, Sang-Yong Kim3
1Graduate School of Pharmaceutical Sciences , Tokushima University , Tokushima 770-8505 , Japan.
Abstract:
Two new dibenzo-1,4-dioxane derivatives, hyperdioxanes A (1) and B (2), were isolated from the roots of a Hypericaceous plant, Hypericum ascyron. Hyperdioxane A (1) is a conjugate of dibenzo-1,4-dioxane and sesquiterpene with an unprecedented heptacyclic ring system. The structures of 1 and 2 were assigned by detailed spectroscopic analyses, including application of a modified Mosher's method. A possible biogenetic pathway of hyperdioxane A (1) from hyperdioxane B (2) and a sesquiterpene, eremophil-9,11(13)-dien-8β,12-olide (3), is presented.
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