6-Amino-3,4-dihydro-4-(3-nitrophenyl)-6-(triphenylphosphoranylidenamino)-3,5-pyridindicarbonsaeure-diethylester 、
异氰酸苯酯 以
乙腈 为溶剂,
反应 6.0h,
以65%的产率得到2-Ethoxy-3,4,5,8-tetrahydro-5-(3-nitrophenyl)-4-oxo-3-phenyl-7-(3-phenylureido)pyrido<2,3-d>pyrimidin-6-carbonsaeure-ethylester