Reference

Structure-activity relationships of vitamin D analogs

Structure-activity relationships of vitamin D analogs. Boris, Alfred (Res. Div., Hoffmann-La Roche Inc., Nutley, N. J., USA). Am. J. Med., 62(4), 543-4, 550-4 (English) 1977. CODEN: AJMEAZ. DOCUMENT TYPE: Journal CA Section: 18 (Animal Nutrition) Section cross-reference(s): 1 In 21-day-old vitamin D-deficient chicks, all analogs tested stimulated 45Ca absorption by the intestine; all but 2 compds. were effective at 1 .mu.g/chick and these 2 were active at higher doses. All analogs stimulated body wt. increase and tibia ash wt. increase in vitamin D-deficient chicks. 1.alpha.-Hydroxy vitamin D3 (I) [41294-56-8] and 1.alpha.,25-dihydroxy vitamin D3 (II) [32222-06-3] were the most effective analogs stimulating 45Cu absorption by 1.5 h for 72 and 76 h, resp., and having relative potencies of 5.5 and 7.5, resp., relative to vitamin D3 in tibia ash wt. 67-97-0 and 56142-94-0 are just another two chemicals used in this study. increase. .

Stimulation of 24R,25-dihydroxyvitamin D3 synthesis by metabolites of vitamin D3

Stimulation of 24R,25-dihydroxyvitamin D3 synthesis by metabolites of vitamin D3. Reddy, G. S.; Jones, Glenville; Kooh, Sang Whay; Fraser, Donald; DeLuca, Hector F. (Res. Inst., Hosp. Sick Child., ON, Can.). Am. J. Physiol., 245(4), E359-E364 (English) 1983. CODEN: AJPHAP. ISSN: 0002-9513. DOCUMENT TYPE: Journal CA Section: 2 (Mammalian Hormones) Structural requirements of the vitamin D mol. necessary to stimulate synthesis of 3H-labeled 24R, 25-dihydroxyvitamin D3 (I) [55721-11-4] in a 1-hydroxylating kidney were examd. Kidneys were perfused with tracer 3H-labeled 25-hydroxyvitamin D3 (II) [19356-17-3] (450 pM) alone and in the presence of a variety of hydroxylated metabolites and fluorinated analogs of vitamin D3 at concns. of 450 pM-25 mM. Tracer [3H]II alone resulted in synthesis of only 3H-labeled 1a,25-dihydroxyvitamin D3 [32222-06-3] during the 6-h perfusion period. 25-Hydroxylated metabolites [II, 25 nM; 1a,25-dihydroxyvitamin D3 [32222-06-3], 25 nM; I, 25 nM; 24,24-difluoro-25-hydroxyvitamin D3 [71603-41-3], 50 nM] stimulated [3H]I prodn. at 2 h of perfusion. Analogs without the 25-hydroxyl group [vitamin D3 [67-97-0], 1a-hydroxyvitamin D3 [41294-56-8], 25-fluorovitamin D3 [63819-58-9], 1a-hydroxy-25-fluorovitamin D3 [64164-40-5], 1a-fluorovitamin D3 [78654-51-0], and 1b-fluorovitamin D3 [88034-84-8]] did not stimulate [3H]I synthesis. Evidently, the 25-hydroxyl group is an essential determinant of 24-hydroxylation.