带活性羟基的疏水的烃化合物胆固醇氨基CLS-NH2

胆固醇是动物组织的主要类固醇成分，也是血浆和几乎所有细胞膜的正常成分。胆固醇是一种带活性羟基的疏水的烃化合物。它是在C-17位置上带有脂族侧链的3-羟基固醇(具有全氢-1，2-环戊烯基菲环骨架)。理论上，胆固醇通过在膜的磷脂之间形成一插入结构，从而在调节细胞膜的透过性和流动性方面起重要作用。

胆固醇或游离存在或与脂肪酸结合成酯存在。胆固醇和胆固醇酯以脂蛋白形式运输，各种脂蛋白所含胆固醇的量不一，以低密度脂蛋白含量最高。生物膜中的胆固醇可以调整膜的流动性以适应不同的功能要求。

胆固醇是由 A、B和C等三个六碳环和一个五碳环D合并而成的环戊烷多氢菲衍生物，共含27个碳原子。环间相互以反式连接，通常取稳定的椅式构像。胆固醇除在5及6位碳之间有双键外，其余的碳多为氢所饱和（故称“多氢”）。各个碳原子的编号如下图所示，式中按惯例略去氢原子，CH3基也只以短线表示，如18、19、21、26和27位碳甲基。3位碳上有一个羟基，17位碳上是1条八碳侧链。环戊烷并菲核心为板状刚性结构，在其上的一端是具挠性的八碳侧链，而在其另一端是羟基。

Cholesterol is the main steroid component of animal tissues and a normal component of plasma and almost all cell membranes. Cholesterol is a hydrophobic hydrocarbon compound with active hydroxyl groups. It is a 3-hydroxysterol with an aliphatic side chain at the C-17 position (with a perhydrogen-1,2-cyclopentenyl phenanthrene ring skeleton). Theoretically, cholesterol plays an important role in regulating the permeability and fluidity of the cell membrane by forming an insertion structure between the phospholipids of the membrane.

Cholesterol exists either free or in combination with fatty acids to form esters. Cholesterol and cholesterol esters are transported in the form of lipoproteins. The amount of cholesterol in various lipoproteins is different, and the content of low-density lipoprotein is the highest. Cholesterol in the biofilm can adjust the fluidity of the membrane to meet different functional requirements.

Cholesterol is a cyclopentane dihydrophenanthrene derivative composed of three six carbon rings a, B and C and one five carbon ring D. It contains a total of 27 carbon atoms. The rings are connected to each other in a reverse manner, usually in a stable chair configuration. Except that there are double bonds between the carbons at positions 5 and 6 of cholesterol, most of the remaining carbons are saturated with hydrogen (hence the name "polyhydrogen"). The numbering of each carbon atom is shown in the figure below. In the formula, hydrogen atom is omitted as usual, and CH3 group is only represented by short lines, such as carbomethyl groups at positions 18, 19, 21, 26 and 27. There is a hydroxyl group on the carbon 3 and an eight carbon side chain on the carbon 17. Cyclopentane phenanthrene core is a plate-like rigid structure, with a flexible eight carbon side chain at one end and a hydroxyl group at the other end.

取用前需放置室温后再打开包装取用防止吸潮，吸潮后活性会降低直至完全失去活性，请务必保持干燥，同时尽量避免频繁的溶解和冻干。