SWEETENING AGENT AND A METHOD OF ITS SYNTHESIS Russian patent published in 1996 - IPC

FIELD: chemistry of amino acids. SUBSTANCE: method of synthesis of substituted amino acids of the formula (I): R-NH-XR′ where X - L-aspartic acid or L-glutamic acid residue; R′ - phenyl, pyridine or pyrimidine containing the following groups at para-position: CN, Cl, C(O)-CH₃ or C(O)-NH₂; R - R₃-CR₁R₂-C(O)--group; R₁ - alkyl-C₁-C₂, phenyl, methoxy, chloro, trihalogenmethyl; R₂ - hydrogen, C₁-C₂-alkyl, methoxy or together with carbon to which R₁ and R₂ are bound form C₃-C₆-cycloalkyl; R₃ - n-alkyl-C₃-C₁₁, alkenyl-C₃-C₇, cycloalkyl-C₃-C₇, phenyl, alkoxy-C₃-C₁₀, C₃-C₆-cycloalkoxy-group which can be substituted with methyl groups at two positions, phenoxy-group. Synthesis is carried out by condensation of L-aspartic or L-glutamic acid that can be protected if necessary at alpha- or beta-carboxyl-group with chloroanhydride of the formula R₃-CR₁R₂-C(O)Cl followed by treatment of synthesized product with amine of the formula R₂-NH₂. EFFECT: improved method of synthesis. 12 cl, 3 tbl