1,25-(OH)2D2 1,25-Dihydroxyergocalciferol 1,25-Dihydroxyvitamin D2 1alpha,25-Dihydroxyvitamin D2 55248-15-2 9,10-Segoergosta-5,7,10(19),22-tetraene-1,3,25-triol, (3beta,5Z,7E,22E)-