5-α-Cholestan-3-β-ol Chemische Eigenschaften,Einsatz,Produktion Methoden
R-S?tze Betriebsanweisung:
R22:Gesundheitssch?dlich beim Verschlucken.
R38:Reizt die Haut.
R40:Verdacht auf krebserzeugende Wirkung.
R48/20/22:Gesundheitssch?dlich: Gefahr ernster Gesundheitssch?den bei l?ngerer Exposition durch Einatmen und durch Verschlucken.
S-S?tze Betriebsanweisung:
S24/25:Berührung mit den Augen und der Haut vermeiden.
S36/37:Bei der Arbeit geeignete Schutzhandschuhe und Schutzkleidung tragen.
S22:Staub nicht einatmen.
Beschreibung
Dihydrocholesterol (cholestanol; 5α-cholestan-3β-ol) is a cholesterol metabolite formed by oxidation and an intermediate in the biosynthesis of chenodeoxycholic acid . Cholestanol (10 μg/ml) induces apoptosis in cornea and lens epithelial cells and increases the activity of IL-1β converting enzyme (ICE) and CPP32 proteases. Dietary administration of 1% cholestanol to mice increases serum and liver cholestanol levels and leads to corneal opacities and gallstones and in rats it leads to cholestanol deposition in the cerebellum. Cholestanol levels are increased in plasma of patients with cerebrotendinous xanthomatosis (CTX), a disease characterized by a deficiency in the mitochondrial enzyme sterol 27-hydrolylase (CYP27A1) that leads to progressive neurological symptoms.
Chemische Eigenschaften
It appears as a white crystalline powder and is odourless. The substance is insoluble in water but readily soluble in organic solvents such as chloroform, ethanol and diethyl ether.1 Its specific rotation is +24.2° (22 °C, in chloroform).
Verwenden
5α-Cholestan-3β-ol is a carbon stanol formed from biohydrogenation of Cholesterol (C432501) in the gut. Studies have also examined the conversion of 5α-Cholestan-3β-ol catalyzed by 3-β-hydroxysteroid
dehydrogenase of rat liver.
Definition
ChEBI: Dihydrocholesterol is a cholestanoid that is (5alpha)-cholestane substituted by a beta-hydroxy group at position 3. It is a 3beta-hydroxy steroid and a cholestanoid. It derives from a hydride of a 5alpha-cholestane.
Allgemeine Beschreibung
Cholestanol is a 5α-dihydro derivative of cholesterol. It acts as a marker for cholesterol absorption. Cholestanol is a steroid with 27 carbon atoms.
l?uterung methode
Purify 5--cholestan-3-ol via acetylation, crystallisation and de-acetylation, then recrystallisation from EtOH or slightly aqueous EtOH, or MeOH. Its solubility is: 0.5% (MeOH) and 1% (EtOH) at 25o. [Mizutani & Whitten J Am Chem Soc 107 3621 1985.] The acetate has m 114-115o from EtOAc/MeOH and, [] D 20 +13o (c 2, CHCl3). [Bruce & Ralls Org Synth Col Vol II 191 1943, Beilstein 6 IV 3577.]
Structure and conformation
The chemical structure of dihydrocholesterol is very similar to that of cholesterol, as both compounds possess the cyclopentanoperhydrophenanthrene steroid nucleus. Its structural features include a β-hydroxyl group at the C3 position of the steroid nucleus and an aliphatic side chain attached at the C17 position. Unlike cholesterol, the C5–C6 double bond is hydrogenated and converted into a saturated single bond in dihydrocholesterol. Accordingly, dihydrocholesterol is systematically named 5α-cholestan-3β-ol.
5-α-Cholestan-3-β-ol Upstream-Materialien And Downstream Produkte
Upstream-Materialien
Downstream Produkte