24,24-Dfhv 24,24-Difluoro-25-hydroxycholecalciferol 24,24-Difluoro-25-hydroxyvitamin D3 71603-41-3 9,10-Secocholesta-5,7,10(19)-triene-3,25-diol, 24,24-difluoro-, (3beta,5Z,7E)-