METHOD FOR SYNTHESIS OF CHOLEST-3ß,5a,6ß,19-TETRAHYDROXY-24-ONE AND ITS DERIVATIVES

摘要

A synthesis process of cholest-3ß,5a,6ß,19-tetrahydroxy-24-one and its derivatives includes the steps of: synthesis of 3ß-acetoxy-cholest-5-en-24-acid with hyodesoxycholic acid as the starting material; synthesis of cholenic acid chloride by reaction with thionyl chloride; reaction with isopropylcadmium reagent under ultrasonic irradiation to produce 3ß-acetoxy-cholest-5-en-24-one; then reaction with N-bromosuccinimide/water solution of perchloric acid system to obtain 3ß-acetoxy-cholest-5a-bromo-6ß-hydroxy-24-one; reaction with diacetoxy iodobenzene to give 3ß-acetoxy-cholest-5a-bromo-6ß,19-epoxy-24-one; reduction with Zn powder/glacial acetic acid system to give 3ß,19-diacetoxy-cholest-5-en-24-one; oxidation of the double bond at position 5 and 6; then hydrolysis to produce cholest-3ß,5a,6ß,19-tetrahydroxy-24-one; finally reaction with methyltriphenylphosphonium bromide to produce 24-methylene-cholest-3ß,5a,6ß,19-tetraol; and reaction with hydrazine to give cholest-3ß,5a,6ß,19-tetrahydroxy-24-dihydrazone. The synthesis process according to the invention has the characteristic of lower price, material availability, scientific and reasonable synthetic routes, higher yield, and the like. The target compounds have significantly protective effect on neuronal apoptosis evoked by low K<SUP>+</SUP>.