The stereochemistry of two monoterpenoid diastereomers from Ferula dissecta

Two diastereomeric monoterpene benzoates, tschimganin and iso-tschimganin, were isolated from the roots of Ferula dissecta. The absolute stereochemistry of the compounds was determined by chemical-related methods and ab initio calculations of electronic circular dichroism and C-13-NMR shifts. The antitumor activities of the diastereomers were also tested.