10α-Hy­droxy-13-{[4-(2-hy­droxy­phen­yl)piperazin-1-yl]meth­yl}-4,9-dimethyl-3,8,15-trioxatetra­cyclo­[10.3.0.0(2,4).0(7,9)]penta­decan-14-one

The title compound, C(25)H(34)N(2)O(6), was synthesized from 9α-hy­droxy­parthenolide (9α-hy­droxy-4,8-dimethyl-12-methyl­ene-3,14-dioxatricyclo­[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 ten-membered ring adopts an approximate chair–chair conformation, while the piperazine ring displays a near regular chair conformation and the five-membered ring an envelope conformation with the C atom closest to the hy­droxy group forming the flap. The mol­ecular conformation is stabilized by an O—H⋯N hydrogen bond, which generates an S(7) loop, and the crystal structure features weak C—H⋯O inter­actions.