α,α-difluorophosphonomethyl azobenzene derivatives as photoregulated phosphoamino acid analogs. 1. Design and synthesis

Article abstract of DOI:10.1016/S0040-4039(99)01400-8

A series of novel, photoregulated phosphoamino acid analogs based on an azobenzene core bearing an α,α-difluoromethylphosphonate as a hydrolytically stable phosphate isostere have been prepared with N-Fmoc protection for use in peptide synthesis. Classes of reagents analogous to both phosphotyrosine and phosphoserine/threonine were prepared by a common route employing a nitrosoarene/aniline condensation to form the azo linkage and the Cu(I)-promoted coupling of an iodoarene with (diethylphosphono)difluoromethyl cadmium bromide (Burton's method) to introduce the phosphonate moiety.