ИСТИНА

Development of synthetic approaches to unnatural polycyclic amino acids and their closest bioisosteric analogues is an actual problem of medicinal and organic chemistry1. Previously we have elaborated the method of synthesis of spirane amino acids I and II, which showed high anxiolytic and tranquilizing activity2. The purpose of this work is to synthesize new amino acid III that is of interest as GABA conformationally restricted bioisosteric phosphonic analogue. The synthesis of amino acid III includes 1) catalytic cycloaddition of diethyl diazomethylphosphonate to double bond of unsaturated ester 1, 2) transformation of CO2Et-group of adduct 2 into amide group using modified Curtsius reaction and 3) hydrolysis of amide and diethoxyphosphoryl groups of spirohexanephosphonate 3.