13-(Imidazol-1-yl)-11,13-di­hydro­melampomagnolide B monohydrate

The title compound, C(18)H(24)N(2)O(4)·H(2)O {systematic name: (1aR,7aS,8R,10aS,10bS,E)-5-hy­droxy­methyl-8-[(1H-imidazol-1-yl)meth­yl]-1a-methyl-2,3,6,7,7a,8,10a,10b-octa­hydro­oxireno[2′,3′:9,10]cyclo­deca­[1,2-b]furan-9(1aH)-one monohydrate}, an imidazole derivative of melampomagnolide B was synthesized under Michael addition conditions. The mol­ecule is built up from fused ten-, five- (lactone) and three-membered (epoxide) rings. The inter­nal double bond of the ten-membered ring identifies it as the cis or E isomer. The lactone ring has an envelope-type conformation, with the (chiral) C atom opposite the lactone O atoms as the flap atom. In the crystal, O—H⋯O, O—H⋯N and weak C—H⋯O hydrogen bonds link the mol­ecules (along with water) into sheets parallel to the bc plane.