FLUORINATED VITAMIN D3 ANALOGUE

摘要

PROBLEM TO BE SOLVED: To obtain the subject new compound effective in the treatment of hypertrophic diseases of skin, the treatment cancers and leukemia, the treatment of sebaceous diseases, especially the treatment of osteoporosis. SOLUTION: This fluorinated vitamin D3 analogue is represented by the formula (X is (H, H) or CH2 ; R1 and R2 are each independently a 1-4C alkyl, a fluoroalkyl, etc.; R3 and R4 are each independently a 3-9C cycloalkyl, a cyclofluoroalkyl, etc.; A is a single bond or a double bond; B is a double bond or triple bond), e.g. 20-methyl analogue of 1α-fluoro-25-hydroxy-23-yn-26,27- hexafluoro-cholecalciferol. The compound of the formula is obtained by eliminating a silyl-protecting group contained therein from a silylated compound of the compound.