One-pot pseudo three-component condensation reaction of arylglyoxal monohydrates with 1-ethyl-2-thioxodihydropyrimidine-4,6(1H,5H)-dione for the synthesis of new pyrano[2,3-d:6,5-d’]dipyrimidines as HIV integrase inhibitor-like frameworks using two different environmentally benign catalytic systems

Simple, selective and highly efficient one-pot synthesis of new 5-aryloyl-1,9-diethyl-2,8-dithioxo-2,3,5,7,8,9-hexahydro-4H-pyrano[2,3-d:6,5-d’]dipyrimidine-4,6(1H)-dione derivatives has been developed using pseudo three-component reaction of arylglyoxal monohydrates with 1-ethyl-2-thioxodihydropyrimidine-4,6(1H,5H)-dione in the presence of a catalytic amount of 1,4-diazabicyclo[2.2.2]octane (DABCO) or ZrOCl2.8H2O as green catalysts in ethanol at 50 °C. The significant features of the present work are simplicity, regio- and chemoselectivity, short reaction times, good to excellent yields, avoiding the use of any hazardous catalyst or solvent, and easy work-up procedure. The structures of the compounds were confirmed by FT-IR, 1H NMR, and 13C NMR spectroscopy data and also microanalysis. The synthetic strategies reported herein can be also regarded as green and efficient methods for the preparation of some HIV integrase inhibitor-like compounds especially new V-165 analogs.