1,2,3,4-Tetrahydro-1,3-dimethyl-2,4-dioxo-6-[(triphenylphosphoranylidene)amino]-5-pyrimidinecarboxylic acid ethyl ester
1,2,3,4-Tetrahydro-1,3-dimethyl-2,4-dioxo-6-[(triphenylphosphoranylidene)amino]-5-pyrimidinecarboxylic acid isopropyl ester
1,2,3,4-Tetrahydro-1,3-dimethyl-2,4-dioxo-6-[(triphenylphosphoranylidene)amino]-5-pyrimidinecarboxylic acid thioethyl ester