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

The title compound, C(25)H(33)BrN(2)O(4), 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 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 an additional ep­oxy ring system and a bromo­phenyl­piperazine group as a substituent. The ten-membered ring adopts an approximate chair–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. An intra­molecular O—H⋯N hydrogen bond stabilizes the mol­ecular conformation. The crystal packing features C—H⋯O hydrogen bonds, which link the mol­ecules into zigzag chains running along the b-axis direction.