PHENYL-GLYCINE DERIVATIVES

摘要

Process for the preparation of compounds (I), wherein A and R<2> are defined as in Claim 1, by reaction of phenyl-glycine (VII) in the presence of alkanol with 1.05-1.3 moles of alkali hydroxide and reacting the mixture with an acid with a higher pH value than 4.3, or by reaction of (VII) with an equivalent amount of alkali salts of acids possessing a higher pH value than 4.3, and condensing the obtained amino acid salt in the presence of alkanol with a compound (VIII) -R<1> is defined as in Claim 1- at the boiling point of the reaction mixture, removing water continuously from the reaction mixture by a binary or ternary azeotropic distillation. The thus obtained compound is optionally reacted with a reactive trifluoro-methane sulphonic acid derivative.