Abstract N-Substituted N′-[6-methyl-2-oxido-1, 3, 2-dioxaphosphinino (5, 4,-b) pyridine-2- yl] ureas have been accomplished by condensation of equimolar quantities of chlorides of various carbamidophosphoric acids (3) with 3-hydroxyl-6-methyl-2-pyridinemethanol (lutidine diol)(4) in the presence of triethylamine in dry toluene–tetrahydrofuran (1: 1) mixture at 45–50 C. Their structures were established by elemental analyses, IR, 1 H NMR, 13 C ...