| abstract |
WHEREIN R1 is defined above, with an alkali metal aluminum hydride, subjecting the resulting cholesta-5,7-diene-1 Alpha ,3 Beta -diol to radiation of ultraviolet rays to obtain 1 Alpha ,3 Beta -dihydroxyprovitamin D3, isomerizing cholesta-1,4,6-trien-3one in the presence of a basic catalyst and reducing the resulting cholesta-1,5,7-trien-3-one with a metal boron hydride. WHEREIN R1 is defined above, with a peroxide, reducing the resulting 1 Alpha ,2 Alpha -epoxide compound represented by the following general formula: WHEREIN R1 represents an alkyl group or an aryl group, reacting the resulting 1,4-cyclized adduct represented by the formula: 1 Alpha -hydroxychlecalciferol is prepared by reacting cholestra-1,5,7-trien-3 Beta -ol with a triazoline-3,5-dione derivative represented by the formula: |