Previtamin D₃

Previtamin D₃
Names
	IUPAC name (3S,6Z)-9,10-Secocholesta-5(10),6,8-trien-3-ol
	Systematic IUPAC name (1S)-4-Methyl-3-[(Z)-2-{(1R,3aR,7aR)-7a-methyl-1-[(2R)-6-methylheptan-2-yl]-2,3,3a,6,7,7a-hexahydro-1H-inden-4-yl}ethen-1-yl]cyclohex-3-en-1-ol
	Other names Previtamin D3
Identifiers
CAS Number	1173-13-3 ; 17592-07-3 ;
3D model (JSmol)	Interactive image;
ChemSpider	78098 ; 4832524 (E)-en ; 9660762 (1S)-1-ol, (E)-en, (1R,7aR)-7a-meth,-1-hept, (2R)-2-yl ; 9375051 (1S)-1-ol, (Z)-en, (1R,7aR)-7a-meth,-1-hept, (2R)-2-yl ;
ECHA InfoCard	100.013.304
EC Number	241-561-3;
MeSH	Previtamin+D(3)
PubChem CID	86590; 6178113 (E)-en; 25245851 (1S)-1-ol, (Z)-en, (2R)-2-yl; 11485943 (1S)-1-ol, (E)-en, (1R,7aR)-7a-meth,-1-hept, (2R)-2-yl; 11199982 (1S)-1-ol, (Z)-en, (1R,7aR)-7a-meth,-1-hept, (2R)-2-yl;
UNII	HDA46400N5 ; 6RR0I9PK8W ;
	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 Key: YUGCAAVRZWBXEQ-UHFFFAOYSA-N ;
	SMILES CC(C)CCCC(C)C1CCC2C(C=CC3=C(C)CCC(O)C3)=CCCC12C;
Properties
Chemical formula	C27H44O
Molar mass	384.648 g·mol−1
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Previtamin D₃ is an intermediate in the production of cholecalciferol (vitamin D₃).

It is formed by the action of UV light, most specifically UVB light of wavelengths between 295 and 300 nm, acting on 7-dehydrocholesterol in the epidermal layers of the skin.^[1]^[2]^[3]

The B ring of the steroid nucleus structure is broken open, making a secosteroid. This then undergoes spontaneous isomerization into cholecalciferol, the prohormone of the active form of vitamin D, calcitriol.

The synthesis of previtamin D₃ is blocked effectively by sunscreens.^[4]

Interactive pathway map

Click on genes, proteins and metabolites below to link to respective articles. ^{[§ 1]}

[[File:

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

|alt=Vitamin D Synthesis Pathway (view / edit)]]

Vitamin D Synthesis Pathway (view / edit)

^ The interactive pathway map can be edited at WikiPathways: "VitaminDSynthesis_WP1531".

References

^ MacLaughlin JA, Anderson RR, Holick MF (May 1982). "Spectral character of sunlight modulates photosynthesis of previtamin D3 and its photoisomers in human skin". Science. 216 (4549): 1001–3. Bibcode:1982Sci...216.1001M. doi:10.1126/science.6281884. PMID 6281884.
^ Webb AR (September 2006). "Who, what, where and when-influences on cutaneous vitamin D synthesis". Progress in Biophysics and Molecular Biology. 92 (1): 17–25. doi:10.1016/j.pbiomolbio.2006.02.004. PMID 16766240.
^ Pope SJ, Holick MF, Mackin S, Godar DE (2008). "Action spectrum conversion factors that change erythemally weighted to previtamin D3-weighted UV doses". Photochemistry and Photobiology. 84 (5): 1277–83. doi:10.1111/j.1751-1097.2008.00373.x. PMID 18513232. S2CID 23246616.
^ Sayre RM, Dowdy JC (2007). "Darkness at noon: sunscreens and vitamin D3". Photochemistry and Photobiology. 83 (2): 459–63. doi:10.1562/2006-06-29-RC-956. PMID 17115796. S2CID 23767593.

This organic chemistry article is a stub. You can help Wikipedia by expanding it.

[WikiPathways-5] The interactive pathway map can be edited at WikiPathways: "VitaminDSynthesis_WP1531".

[pmid6281884-1] MacLaughlin JA, Anderson RR, Holick MF (May 1982). "Spectral character of sunlight modulates photosynthesis of previtamin D3 and its photoisomers in human skin". Science. 216 (4549): 1001–3. Bibcode:1982Sci...216.1001M. doi:10.1126/science.6281884. PMID 6281884.

[pmid16766240-2] Webb AR (September 2006). "Who, what, where and when-influences on cutaneous vitamin D synthesis". Progress in Biophysics and Molecular Biology. 92 (1): 17–25. doi:10.1016/j.pbiomolbio.2006.02.004. PMID 16766240.

[pmid18513232-3] Pope SJ, Holick MF, Mackin S, Godar DE (2008). "Action spectrum conversion factors that change erythemally weighted to previtamin D3-weighted UV doses". Photochemistry and Photobiology. 84 (5): 1277–83. doi:10.1111/j.1751-1097.2008.00373.x. PMID 18513232. S2CID 23246616.

[pmid17115796-4] Sayre RM, Dowdy JC (2007). "Darkness at noon: sunscreens and vitamin D3". Photochemistry and Photobiology. 83 (2): 459–63. doi:10.1562/2006-06-29-RC-956. PMID 17115796. S2CID 23767593.

[1]

[2]

[3]

[4]

[§ 1]