Jasomontanone, a novel bicyclic sesquiterpene from the leaves of Jasonia montana

Abstract

A novel rearranged eudesmane sesquiterpene with a new 5/7 membered bicyclic-ring-system, jasomontanone, was isolated from Jasonia montana. Its structure was determined as (3aR*, 6R*, 8aR)-3a-(hydroxymethyl)-6- (2-hydroxy-propan-2-yl)-8amethyl- octahydrazulen-4(5H)-one by analysis of spectroscopic data (IR, HR-MS, 1H and 13C NMR), including 2D NMR (1H-1H COSY, HMQC, HMBC and NOESY), chemical transformation, and biogenetic consideration.