6,8-Dihy-droxy-8a-methyl-3,5-dimethyl-idenedeca-hydro-naphtho-[2,3-b]furan-2(3H)-one.

Abstract

This study reports the crystal structure of C15H20O4, a eudesmanolide-type sesquiterpene lactone obtained from the Chinese medicinal plant Carpesium triste Maxim. The molecular framework consists of three rings: two fused six-membered rings adopting chair conformations and one five-membered ring in a flattened envelope conformation. Within the crystal lattice, two hydroxyl groups participate in both intramolecular and intermolecular O-H···O hydrogen bonding. The hydrogen atoms associated with these groups exhibit positional disorder, with site-occupation factors of 0.5. Intermolecular hydrogen bonds organize the molecules into chains extending along the [010] direction.