(3-cholestene-3β-ol oleyl carbonate)

Cholesterol can be esterified with a fatty acid to form cholesteryl esters which form discrete lipid droplets in cells, especially in cells of steroidogenic tissues, and in the lipid core of low-density lipoproteins in the blood.

Some cholesterol is absorbed from dietary sources.

The High level of cholesterol in the blood is a major risk factor for coronary heart diseases.
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Oct 28, 2009 · Synthesis of Cholesterol Nonanoate ..

T1 - The synthesis of the chiral non-mesogenic D-seco estrone derivatives and their influence on the phase transitions of cholesteric liquid crystals

what would be the theoretical yield of cholesteryl nonanoate

Cholesterol and its derivatives have drawn much attention because of their relevance to biology. They have also been studied at the air−water (A−W) interface. Here, we have systematically investigated the two-dimensional (2D) and three-dimensional (3D) phases of cholesteryl derivatives at the A−W interface employing surface manometry, epifluorescence, Brewster-angle and reflection microscopy techniques. We found that the short-chain ester cholesteryl acetate forms a stable monolayer. The higher homologues cholesteryl heptanoate and cholesteryl octanoate do not form monolayers; they yield 3D crystallites at very large area per molecule. Interestingly, we found cholesteryl nonanoate to be in the crossover regime in the homologous series of cholesteryl esters. It spontaneously forms a fluidlike bilayer at the A−W interface. The higher homologue cholesteryl laurate forms an unstable bilayer phase. The long-chain esters cholesteryl myristate, cholesteryl palmitate, and cholesteryl stearate exhibit crystalline bilayer and 3D structures. Cholesteryl benzoate, which contains a bulkier phenyl group instead of the flexible alkyl chain, forms a crystalline bilayer. We discuss the assembly of molecules in the different phases at the A−W interface for the cholesteryl derivatives with respect to their packing in the bulk and the onset of the smectic liquid-crystalline phase.

Cholesteric materials are temperature sensitive and have color changing ability upon temperature.
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Cholesterol nonanoate | C36H62O2 | ChemSpider

AB - The synthesis of new chiral seco-estrone derivatives is presented, as well as their influence on the phase transition of binary mixtures of cholesteryc liquid crystals. The new chiral derivatives do not posses any liquid crystalline phases and were synthesized in several synthetic steps, starting from estrone. We have studied the mixtures of cholesteryl non-anoate (40%) with cholesteryl myristate (40%) and addition of new chiral derivatives 3, 4, or 5 (20%). It was concluded that the addition of chiral derivative 3 to the binary mixture stabilizes smectic A and cholesteric phase and shifts the phase transition temperature with respect to pure binary mixture for about 5°C towards lower temperatures. The extension of the temperature range of the cholesteric phase from 5°C to 15°C was established in the case when the derivatives 3 and 4 are added to the binary mixture of cholesteryl nonanoate with cholesteryl myristate. The phase diagrams of investigated compounds are formed on the basis of data obtained by the optical microscopy. Using X-ray diffraction on the crystalline powder of unoriented samples we have determined the molecular parameters: the thickness of smectic and cholesteric layers and average distance between the long axes of neighboring molecules.

Search results for Cholesteryl nonanoate at Sigma-Aldrich

Cholesteryl nonanoate is used in hair colors, cosmetic products like lip products, lotions. It is also used in the manufature of some pleochroic dyes. It can be also used as a component of the liquid crystals used for liquid crystal displays.

Blue phases of cholesteryl nonanoate - SAO/NASA ADS

The largest concentration of cholesterol is in the myelin sheath that surrounds nerves and in the plasma membrane that surrounds all cells in vertebrates (25% of brain lipid is cholesterol).