| abstract |
NEW MATERIAL: A compound of formula I (wherein R 1 is H or hydroxyl; and R 2 is H or F). n EXAMPLE: 1α,25-dihydroxy-23,24-didehydro-26,26,26,27,27,27- hexafluorochlolecalciferol. n USE: Useful for the treatment of renal osteodyptrophy, especially osteoprosis. This is useful as a medicine for leukemia because it inhibits the propagation of cells and induces the differentiation of cells. n PREPARATION: According to the reaction formula, a compound of formula III [wherein R 4 is Si(R 5 ) 3 (wherein R 5 is a 1-8C alkyl or the like)] or formula IV (wherein R 3 is R 4 ) is obtained from a compound of formula II. After the hydroxyl derivative group is removed from the compound, it is treated with an organic fluoride salt (e.g. tetrabutylammonium fluoride) at desirably room temperature in a solvent (e.g. THF) to obtain a compound of formula Ia or Ib. n COPYRIGHT: (C)1990,JPO |