9α-hydroxy-12-{[4-(4-hydroxyphenyl)piperazin-1-yl]methyl}-4, 8-dimethyl-3,14-dioxatricyclo[9.3.0.02,4]tetradec-7-en-13-one

Abstract

The title compound, C25H34N2O5, was synthesized from 9α-hydroxyparthenolide (9α-hydroxy-4,8- dimethyl-12-methylen-3, 14-dioxa-tricyclo[9.3.0.02,4]tetradec-7-en- 13-one), which in turn was isolated from the chloroform extract of the aerial parts of Anvillea radiata. The molecule comprises a ten-membered ring fused to a five-membered ring with an additional epoxy ring system fused to the ten-membered ring. The five-membered ring also carries a 4-hydroxyphenyl- piperazin-1-ylmethyl substituent. The ten-membered ring adopts an approximate chair-chair conformation, while the piperazine ring displays a chair conformation and the five-membered ring shows an envelope conformation with the C atom closest to the hydroxy group forming the flap. Two C atoms in the phenyl ring and the O atom of the hydroxyl group are disordered over two sites, with an occupancy ratio of 0.53(5):0.47(5). An intramolecular O - H⋯N hydrogen-bond stabilizes the molecular conformation. In the crystal, C - H⋯O hydrogen bonds link the molecules into zigzag chains running along the a-axis direction. © 2014 CrossMark.