10α-Hydroxy-4,9-dimethyl-13-[(pyrrolidin-1-yl)methyl]-3,8,15-trioxatetracyclo[10.3.0.02,4.07,9]pentadecan-14-one

Abstract

The title compound, C19H29NO5, was synthesized from 9α-hydroxyparthenolide (9α-hydroxy-4,8-dimethyl-12-methylene-3,14-dioxatricyclo[9.3.0.02,4]tetradec-7-en-13-one), which was isolated from the chloroform extract of the aerial parts of Anvillea radiata. The molecule is built up from two fused five- and ten-membered rings with the (pyrrolidin-4-yl)methyl group as a substituent. The two five-membered ring display the same envelope conformations, whereas the ten-membered ring adopts an approximate chair–chair conformation. The dihedral angle between the ten-membered ring and the lactone ring is 21.81 (9)°. An intramolecular O—H...N hydrogen bond stabilizes the molecular conformation. In the crystal, intermolecular C—H...O interactions link the molecules into chains parallel to the c axis.