An Efficient One-pot Two-component Protocol for Regio- and Chemoselective Synthesis of 5-Aryloyl-1,3,7,9-tetraalkyl-2,8-dithioxo-2,3,8,9-tetrahydro- 1H-pyrano[2,3-d:6,5-d’]dipyrimidine-4,6(5H,7H)-diones

Novel symmetric fused pyrano[2,3-d]pyrimidine derivatives were synthesized in 75-92% yield by a one-pot two-component reaction of arylglyoxals and 1,3-dialkyl-2-thiobarbituric acids in ethanol at room temperature. This is the first protocol to be reported for the synthesis of 5-aryloyl-1,3,7,9-tetraalkyl- 2,8-dithioxo-2,3,8,9-tetrahydro-1H-pyrano[2,3-d:6,5-d′]dipyrimidine-4, 6(5H,7H)-diones and the significant features of the present protocol are simplicity, high yields, a simple isolation procedure, and high chemoselectivity.