Abstract
The reactions of 6-acetyl- 3-amino-4- imino-7-methyl-5-phenyl-3,5-dihydro-4H-pyrano[2,3-d]pyrimi dine with triethyl phosphite and some electrophilic reagents, namely 1,2-dibromoethane, oxalyl chloride, chloroacetyl chloride, and ethyl chloroacetate, were studied. These one-pot three-component reactions regioselectively afforded four new 11-acetyl-2-ethoxy-10-methyl-12- phenylpyrano[2',3':4,5]pyrimido[1,6-b][1,2,4,5.5]triazaphosphepin-2-ones in 69-73% yields.