A series of 6-amino-4-aryl-2-thioxo-1,2,3,4-tetrahydropyrimidine-5-carbonitriles was synthesized, further reaction of which with dimethyl chloroethynylphosphonate yielded a series of new dimethyl (8-cyano-7-aryl-5-thioxo-5,6-dihydroimidazo[1,2-c]pyrimidin-2-yl)phosphonates.