An X-Ray Crystallographic Study on the Absolute Configuration of Dihydroyashabushiketol and the Solvent-dependence of Its Optical Rotation

Abstract
The absolute configuration of dihydroyashabushiketol was established to be S on the basis of the X-ray crystallographic analysis of the 4′,4″-dibromo derivative. In addition, it was found that the sense of the optical rotations of dihydroyashabushiketol and its dibromo derivative is determined by the interaction of their C-5 hydroxyl group with the solvent used for the measurements.