| abstract |
The invention relates to a process for preparing N-Phosphonoformylaminosaeuren and their derivatives of the formula I, by reacting bis-trimethylsilyl phosphite with Isocyanatocarbonsaeureestern, at elevated temperature to N- (bis (trimethylsilyl) phosphonoformyl) amino acid esters, which by means of alkaline solvolysis in Compounds of formula I can be converted, wherein R1 is trimethylsilyl, hydrogen, an alkali metal, ammonium, substituted ammonium radical; R2 is alkyl of C1 to C4, hydrogen or an alkali metal; A is branched or unbranched, substituted or unsubstituted alkylene of C1 to C9, cycloalkylene or heterocyclic radical. N-phosphonoformylamino acids have antiviral properties. Formula I |