7-Dehydrocholesterol

  • (3S, 10R, 13R, 17R ) -10.13 - dimethyl- 17 - (6- methylheptan- 2-yl) - 2,3,4,9,11,12,14,15,16,17 - decahydro - 1H- cyclopenta [ a] phenanthren -3-ol
  • Cholesta -5 ,7-dien- 3β -ol
  • Provitamin D3

White solid

Fixed

148-152 ° C

Template: Infobox chemical / molecular formula search available

7-dehydrocholesterol is a sterol which is the precursor of cholesterol, and Cholecalciferol (vitamin D3). 7- dehydrocholesterol was discovered by later Nobel Laureate Adolf Windaus.

Function

Formation of cholesterol

The enzyme 7- dehydrocholesterol reductase 7- dehydrocholesterol to cholesterol is reduced.

This enzyme is restricted in the Smith - Lemli -Opitz syndrome is caused by mutations in its activity differently. This means that in this syndrome 7 Dehydrocholesterolspiegel in the blood is high and the cholesterol is too low. Cholesterol in turn is used as a starting material for steroid hormones and bile acids.

Formation of vitamin D

Photolysis with UVB light of wavelengths 270-315 nm 7- dehydrocholesterol is first further converted into provitamin D3 and by thermal isomerization to vitamin D3. 7- dehydrocholesterol is found mainly in the stratum spinosum and stratum basale of the skin.

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