Cholesterol

(3β)-cholest-5-en-3-ol
Systematic name 2,15-dimethyl-14-(1,5-dimethylhexyl)tetracyclo[8.7.0.02,7.011,15]heptacos-7-en-5-ol
Other names (10R,13R)-10,13-dimethyl-17-(6-methylheptan-2-yl)-2,3,4,7,8,9,11,12,14,15,16,17-dodecahydro-1H-cyclopenta[a]phenanthren-3-ol, Cholesterin, Cholesteryl alcohol [1]
Identifiers
CAS number	57-88-5
PubChem	5997
ChemSpider	5775
UNII	97C5T2UQ7J
KEGG	D00040
ChEBI	CHEBI:16113
ChEMBL	CHEMBL112570
Jmol-3D images	Image 1
SMILES C[C@H](CCCC(C)C)[C@H]1CC[C@@H]2[C@@]1(CC[C@H]3[C@H]2CC=C4[C@@]3(CC[C@@H](C4)O)C)C
InChI InChI=1S/C27H46O/c1-18(2)7-6-8-19(3)23-11-12-24-22-10-9-20-17-21(28)13-15-26(20,4)25(22)14-16-27(23,24)5/h9,18-19,21-25,28H,6-8,10-17H2,1-5H3/t19-,21+,22+,23-,24+,25+,26+,27-/m1/s1  Key: HVYWMOMLDIMFJA-DPAQBDIFSA-N  InChI=1/C27H46O/c1-18(2)7-6-8-19(3)23-11-12-24-22-10-9-20-17-21(28)13-15-26(20,4)25(22)14-16-27(23,24)5/h9,18-19,21-25,28H,6-8,10-17H2,1-5H3/t19-,21+,22+,23-,24+,25+,26+,27-/m1/s1 Key: HVYWMOMLDIMFJA-DPAQBDIFBB
Properties
Molecular formula	C27H46O
Molar mass	386.65 g/mol
Appearance	white crystalline powder[2]
Density	1.052 g/cm3
Melting point	148–150 °C[2]
Boiling point	360 °C (decomposes)
Solubility in water	0.095 mg/L (30 °C)
Solubility	soluble in acetone, benzene, chloroform, ethanol, ether, hexane, isopropyl myristate, methanol
Hazards
Flash point	209.3 ±12.4°C [1]
(verify) (what is: /?) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)

Cholesterol, from the Ancient Greek chole- (bile) and stereos (solid) followed by the chemical suffix -ol for an alcohol, is an organic molecule. It is a sterol (or modified steroid),^[3] and an essential structural component of animal cell membranes that is required to establish proper membrane permeability and fluidity. Cholesterol is thus considered within the class of lipid molecules.
In addition to its importance within cells, cholesterol also serves as a precursor for the biosynthesis of steroid hormones, bile acids, and vitamin D.^[4] Cholesterol is the principal sterol synthesized by animals; in vertebrates it is formed predominantly in the liver. It is almost completely absent among prokaryotes (i.e., bacteria), although there are some exceptions such as Mycoplasma, which require cholesterol for growth^{[citation needed]}.
François Poulletier de la Salle first identified cholesterol in solid form in gallstones in 1769. However, it was not until 1815 that chemist Michel Eugène Chevreul named the compound "cholesterine".