title: An improved procedure for the isolation of suprasterol2 I and II from a photochemical reaction mixture of ergocalciferol (vitamin D2).
abstract: An improved procedure for the isolateion suprasterol2 I and II from a photochemical reaction mixture of ergocalciferol (vitamin D2) and their spectral data are described in this paper. When a solution of ergocalciferol in ethanol was irradiated by UV light from a high-pressure mercury lamp, the reaction mixture gave six spots, including suprasterol2 I and II, on the thin-layer chromatogram, while the peaks corresponding to pyro-D2, isopyro-D2,5,b-trans-D2, suprasterol 2 I and II were observed in the gas chromatogram obtained from a capillary column GLC (Suprasterol2 I and II were main peaks). After purifying the mixture by column chromatography on silica gel containing 12% alumina as an absorbent, two main fractins were isolated. The data of their spectra, TLC and GLC showed that the former fraction was suprasterol2 II while the latter was suprasterol2 I and that the both fractions contained the respective compound only. Both suprasterol2 were crystallized as the 3,5-dinitro-benzoates.
mesh_terms: D003525:Cyclosteroids / Q000032:analysis / Q000302:isolation & purification; D004872:Ergocalciferols / Q000528:radiation effects*; D013261:Sterols / Q000032:analysis / Q000302:isolation & purification*; D014466:Ultraviolet Rays
chemical_list: D003525:Cyclosteroids; D004872:Ergocalciferols; D013261:Sterols