Cholestenes are chiral molecules that are derivatives of

cholestanes Cholestane is a Saturated and unsaturated compounds, saturated tetracyclic steroid biosynthetically derived from triterpenoids. This 27-carbon biomarker is produced by diagenesis of cholesterol and is one of the most abundant biomarkers in the roc ...

that have a

double bond In chemistry, a double bond is a covalent bond between two atoms involving four bonding electrons as opposed to two in a single bond. Double bonds occur most commonly between two carbon atoms, for example in alkenes. Many double bonds exist betw ...

. If there are two double bonds, the molecule is known as a "cholestadiene". Examples include

fusidic acid Fusidic acid, sold under the brand name Fucidin among others, is a steroid antibiotic that is often used topically in creams or ointments and eyedrops but may also be given systemically as tablets or injections. , the global problem of ad ...

lanosterol Lanosterol is a tetracyclic triterpenoid and is the compound from which all animal and fungal steroids are derived. By contrast, plant steroids are produced via cycloartenol. In the eyes of vertebrates, lanosterol is a natural constituent, havin ...

, and

stigmasterol Stigmasterol – a plant sterol (''phytosterol'') – is among the most abundant of plant sterols, having a major function to maintain the structure and physiology of cell membranes. In the European Union, it is a food additive listed with E nu ...

. Cholestene is a widely available chemical, used and sold commercially with

red yeast rice Red yeast rice or red rice ''koji'' is a bright reddish purple fermented rice, which acquires its color from being cultivated with the mold '' Monascus purpureus''. Red yeast rice is what is referred to as a '' kōji'' in Japanese, meaning "gr ...

. There are also derivatives of the molecule, such as 5-cholestene and 2-cholestene. These molecules differ by the placement of a double bond in one of its cyclohexane rings.

Preparation

Cholestene has been synthetically prepared to mimic

cholesterol Cholesterol is the principal sterol of all higher animals, distributed in body Tissue (biology), tissues, especially the brain and spinal cord, and in Animal fat, animal fats and oils. Cholesterol is biosynthesis, biosynthesized by all anima ...

, as they are used as important molecules to help important tools in the field of bioorganic and medicinal chemistry. Examples include facilitating siRNA transportation, enhancing DNA transfection, and potentially targeting tumors. In particular, researchers are interested in 3''β''-amino-5-cholestene, as it has a high affinity for phospholipid membranes. 3''β''-amino-5-cholestene, as well as other 3''β''-Derivatives, can be optimally synthesized from

Cholesterol Cholesterol is the principal sterol of all higher animals, distributed in body Tissue (biology), tissues, especially the brain and spinal cord, and in Animal fat, animal fats and oils. Cholesterol is biosynthesis, biosynthesized by all anima ...

. The reaction scheme of 3''β''-amino-5-cholestene is shown below and adapted from Sun et al: ''Figure 1: Multi-step Synthesis of 3β-amino-5-cholestene.''

Applications

Cholestene has been used as a dietary supplement and is often sold with

to promote

management. However, these products contain a hidden drug ingredient,

lovastatin Lovastatin, sold under the brand name Mevacor among others, is a statin medication, to treat high blood cholesterol and reduce the risk of cardiovascular disease. Its use is recommended together with lifestyle changes. It is taken by mouth. ...

, that may cause serious side effects when combined with other medications, such as muscle injury. Individuals with

liver dysfunction Liver disease, or hepatic disease, is any of many diseases of the liver. If long-lasting it is termed chronic liver disease. Although the diseases differ in detail, liver diseases often have features in common. Liver diseases File:Ground glas ...

or taking medication that weakens liver metabolism are at greater risk for these side effects, which may appear as muscle weakness, pain, fatigue and dark coloured urine. In biological research, 3β-amino-5-cholestene (also referred to as aminocholesterol), a 3''β''-derivative of cholestene, has been shown to selectively enhance the

magnetic susceptibility In electromagnetism, the magnetic susceptibility (; denoted , chi) is a measure of how much a material will become magnetized in an applied magnetic field. It is the ratio of magnetization (magnetic moment per unit volume) to the applied magnet ...

lanthanide The lanthanide () or lanthanoid () series of chemical elements comprises at least the 14 metallic chemical elements with atomic numbers 57–70, from lanthanum through ytterbium. In the periodic table, they fill the 4f orbitals. Lutetium (el ...

-chelating bicelles. When an aminocholesterol conjugate is used with different lanthanide ions, it can possibly fine tune a bicelle's magnetic susceptibility.

Derivatives

2-Cholestene

5-Cholestene

References