Transphosphorylative Spin-Labeling Utilizing Diimidazolides of Pentavalent Phosphorus

Abstract

The reaction of the spin-labeled diimidazolide 1 with hydroxy and amino compounds was studied. Diimidazolide 1 was superior to the dichloridate 6 for the preparation of spinlabeled phosphates 3 and phosphorodiamidates 2. The spin-labeled phosphate 15 was synthesized through hydrolysis of 6. Spin-labeled cyclophosphoramidates (10-13), analogs of the cytotoxic Endoxan, were prepared by the reaction of 1 and 6 with the appropriate difunctional nucleophile. Inductive effects of substituents in the imidazolyl moiety on the transphosphorylation reaction were also studied. [xxx]