Theoretical assessment of the mechanisms involved in the cholesterol biosynthesis from lanosterol

Abstract

A theoretical approach to describe the mechanisms of the isomerization and reduction of a double bond, involved in the lanosterol conversion to cholesterol was undertaken. Also, the 14alpha-demethylation and 4alpha-demethylation in this biosynthesis were studied, and some similarities were found between the two

however they are different and their mechanisms have not been explained yet. Ab initio calculations were performed in order to prove these mechanisms. Two different characteristics involved in this biosynthesis were explained, namely (i) the stability of each molecule during this reaction using total energy, hardness and dipole moment, and (ii) the explanation of proposed mechanisms [Steroid Biochemistry and Pharmacology, 1970, p. 57] of the two different reactions. using frontier orbitals and atomic charges. For this sequence of reactions, the hardness and dipole moment indicate the hydro-solubility of the molecules, which means that carrying properties change through cell membrane, It is possible to explain the reaction mechanisms using frontier molecular orbitals theory and the atomic charge. The localization of highest occupied molecular orbital, lowest unoccupied molecular orbital and the flow of atomic charge are in agreement with reported mechanisms (C) 2002 Elsevier Science B.V. All rights reserved.