Pharma & Specialty Chemical Standards

Cholesterol, IUPAC name (3S,5Z,9E,11S,15R)-11-hydroxy-15-methyl-2,3-epoxy-7,24-dimethylcholest-5,9(11)-diene-3-ol, has molecular formula C₂₇H₄₆O and molecular weight 386.65 g/mol. A steroid alcohol (sterol class), it features a tetracyclic cyclopentanoperhydrophenanthrene ring system with a hydroxyl group at C3 and an 8-carbon alkyl side chain. It serves as a precursor for bile acids, steroid hormones, and vitamin D synthesis. Physicochemically, it is a waxy, amphipathic lipid with high membrane solubility. Mechanistically, it modulates membrane fluidity and acts as a substrate in biosynthetic pathways, influencing cellular signaling and lipid homeostasis.