Crystal and molecular structure of schkuhriolid monohydrate, a cis, trans-germacra-1(10),4-dien-cis-8,12-olide
Abstract
The crystal structure of the title compound (I) has been determined from three-dimensional X-ray diffractometer data by direct methods. Crystals are orthorhombic, space group P212121, with Z= 4 in a cell of dimensions. a= 6.968(1), b= 9.603(1), c= 22.478(3)Å. Schkuhriolid is a representative of the germacra-cis-1(10), trans-4-diene class of sesquiterpene, sub-group melampolide. The ten-membered ring conformation in schkuhriolid is similar to that found in crystal structures of other malampolides though the mode of the attachment of the γ-lactone ring is different. Schkuhriolid, with a lactone ring closed at C(8) and cis-annelated to the homocyclic ring is the first such melampolide studied by X-ray diffraction.