Tetrabutylammonium Hydrogensulphate Catalyzed Efficient Synthesis of Glycosyl(aryl) Dihydropyrimidinones

An efficient synthesis of glycosyl dihydropyrimidinones using a three-component reaction of a α- keto ester, glycosyl aldehyde, urea (or thiourea) in the presence of tetrabutylammonium hydrogensulphate and diethylene glycol as eco-friendly solvent has been reported. The reaction has been extended to the synthesis of aryl dihydropyrimidinones also. The glycosyl dihydropyrimidinones were obtained in excellent yields in less time than the methods already reported.