Synthesis, molecular docking, and in silico ADME studies of dihydropyrimidine derivatives using tetrabutylphosphonium methanesulphonate ionic liquid as a catalyst under solvent-free conditions

Abstract

This paper describes the synthesis and characterization of tetrabutylphosphonium methanesulphonate ionic liquid and its use for the first time as a catalyst in a multicomponent reaction for one-pot synthesis of dihydropyrimidine derivatives from various aromatic aldehydes, methyl or ethyl acetoacetate, and urea or thio-urea under solvent-free conditions at 120 °C. About 21 different dihydropyrimidine derivatives have been synthesized in excellent yields. The advantages of this method are the following: solvent-free conditions, a small amount of catalyst required, shorter reaction time, easy workup procedure, and no hazardous organic solvents or toxic catalysts. This catalyst was easily prepared and showed an excellent level of reusability. The molecular docking study was performed to evaluate interactions between the active compounds with Leishmania pteridine reductase 1 (PTR1). Using theoretical evaluation, ADME properties in silico were investigated for their oral bioavailability to predict the safer efficacy of the synthesized compounds.