Studies of Active Substances in Herbs Used for Hair Treatment. IV. The Structure of the Hair Regrowth Substance, Polyporusterone A, from Polyporus umbellatus F.

抄録

The crystal structure of polyporusterone A, from Polyporus umbellatus F. was determined by X-ray diffraction analysis. The crystals are orthorhombic, space group P2₁2₁2₁, Z=4, unit-cell dimension a=17.968(2), b=26.201(5), c=6.227(1) Å. The structure, (+)-2β, 3β, 14α, (20R, 22R)-pentahydroxy-(24S)-methyl-5β-cholest-7-en-6-one, was solved from diffractometric data by direct methods and refined by least-squares calculations to R=0.053 (2345 observed independent significant reflections (I>3σ(I)). All the hydroxyl groups are involved in a hydrogen-bonding network. The NMR data indicate that the side-chain has the same conformation in both the crystalline state and solution.