9α-Hy­droxy-12-{[4-(4-hy­droxy­phen­yl)piperazin-1-yl]meth­yl}-4,8-dimethyl-3,14-dioxatri­cyclo­[9.3.0.0(2,4)]tetra­dec-7-en-13-one

The title compound, C(25)H(34)N(2)O(5), was synthesized from 9α-hy­droxy­parthenolide (9α-hy­droxy-4,8-dimethyl-12-methylen-3, 14-dioxa-tri­cyclo­[9.3.0.0(2,4)]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.