1,25-Dihydroxycholecalciferol-26-23-lactone 1,25-Lactone 1,25-dihydroxyvitamin D3-26,23-lactone 1alpha,25-Dihydroxyvitamin D3-26,23-lactone 23(S),25(R)-1,25(OH)2D3-26,23-Lactone 81203-50-1 9,10-Secocholesta-5,7,10(19)-trien-26-oic acid, 1,3,23,25-tetrahydroxy-, gamma-lactone, (1alpha,3beta,5Z,7E,22S,25R)- Calcitriol-26,23-lactone