1,25-dihydroxy Vitamin D2

1,25-dihydroxy Vitamin D2 is the active circulating metabolite of vitamin D2 formed by 25-hydroxylase in the liver and 25-hydroxyvitamin D-hydroxylase in the kidney. By binding to the vitamin D receptor (VDR), 1,25-dihydroxy Vitamin D2 activates VDR to interact with the retinoid X receptor (RXR), forming the VDR/RXR/cofactor complex, which regulates gene transcription. Because 1,25-dihydroxy Vitamin D2 circulates at picomolar concentrations and is highly lipophilic, it is difficult to quantify.Formal Name: (1R,3S,5Z)-4-methylene-5-[(2E)-2-[(1R,3aS,7aR)-octahydro-1-[(1R,2E)-5-hydroxy-1,4,5-trimethyl-2-hexen-1-yl]-7a-methyl-4H-inden-4-ylidene]ethylidene]-1,3-cyclohexanediol. CAS Number: 60133-18-8. Synonyms: Ercalcitriol, Ro 17-6218. Molecular Formula: C28H44O3. Formula Weight: 428.7. Purity: >98%. Formulation: (Request formulation change), A crystalline solid. Solubility: Ethanol: 1 mg/ml. SMILES: O[C@H]1C[C@H](O)C(/C(C1)=C\C=C2CCC[C@@]3(C)[C@@]/2([H])CC[C@]3([H])[C@H](C)/C=C/[C@H](C)C(O)(C)C)=C. InChi Code: InChI=1S/C28H44O3/c1-18(9-10-19(2)27(4,5)31)24-13-14-25-21(8-7-15-28(24,25)6)11-12-22-16-23(29)17-26(30)20(22)3/h9-12,18-19,23-26,29-31H,3,7-8,13-17H2,1-2,4-6H3/b10-9+,21-11+,22-12-/t18-,19+,23-,24-,25+,26+,28-/m1/s1. InChi Key: ZGLHBRQAEXKACO-XJRQOBMKSA-N.