Synthesis of Some Biginelli Compounds from Thiosemicarbazide, Urea and Thiourea

Abstract

Synthesis of some 1-amino-5-acetyl-6-methyl-4-aryl-3,4-dihydropyrimidine -2- thione and 1-amino arylmethylidiene -5- acetyl -6- methyl -4-aryl-3,4- dihydropyrimidine-2-thione, from reaction of acetyl acetone, thiosemicarbazide and aldehyde was achieved. Synthesis of some 1-amino-5-ethoxycarbonyl-6- methyl-4-aryl-3,4-dihydropyrimidine-2-thione and 1-amino arylmethylidiene-5- ethoxycarbonyl -6-methyl- 4-aryl- 3,4-dihydropyrimidine-2-thione was accomplished by reaction of ethyl acetoacetate, thiosemicarbazide and aldehyde. The reaction was carried out in presence of ZnCl2 as catalyst. Synthesis of 5- acetyl-6-methyl-4-aryl-3,4-dihydropyrimidine-2-one, 5-acetyl-6-methyl-4-aryl-3,4- dihydropyrimidine-2-thione, 5-ethoxycarbonyl-6-methyl -4- aryl -3,4- dihydro pyrimidine-2-one and 5- ethoxycarbonyl-6-methyl-4-aryl-3,4- dihydro pyrimidine- 2-thione the reaction was accomplished without catalyst. The reaction progress was followed by TLC analysis and the chemical structure confirmed by spectroscopic analysis (UV, IR, ¹HNMR, ¹³CNMR and MS)