Previtamin D3

• CAT Number: R058278
• CAS Number: 1173-13-3
• Molecular Formula: C27H44O
• Molecular Weight: 384.64
• Purity: ≥95%
• Synonyms: (1S)-3-[(Z)-2-[(1R,3aR,7aR)-7a-methyl-1-[(2R)-6-methylheptan-2-yl]-1,2,3,3a,6,7-hexahydroinden-4-yl]ethenyl]-4-methylcyclohex-3-en-1-ol
• InChI: InChI=1S/C27H44O/c1-19(2)8-6-9-21(4)25-15-16-26-22(10-7-17-27(25,26)5)12-13-23-18-24(28)14-11-20(23)3/h10,12-13,19,21,24-26,28H,6-9,11,14-18H2,1-5H3/b13-12-/t21-,24+,25-,26+,27-/m1/s1
• InChIKey: YUGCAAVRZWBXEQ-WHTXLNIXSA-N
• SMILES: CC1=C(C[C@H](CC1)O)/C=C\C2=CCC[C@]3([C@H]2CC[C@@H]3[C@H](C)CCCC(C)C)C

Previtamin D3（Cat No.:R058278）is a photochemical intermediate formed in the skin when 7-dehydrocholesterol absorbs ultraviolet B (UVB) radiation. Structurally, it is a secosteroid produced through the photolysis of the steroidal B-ring, creating a triene system. Previtamin D3 is thermodynamically unstable and undergoes a heat-driven isomerization to form vitamin D3 (cholecalciferol), the biologically relevant precursor to active vitamin D metabolites. Its role is essential in the cutaneous vitamin D biosynthesis pathway, linking sunlight exposure to calcium homeostasis, bone health, and broader endocrine and immunological regulation.