The invention pertains to medicine, specifically to methods of obtaining biologically active substances with immunoregulatory properties, and can be used in medicine, veterinary science and experimental biochemistry. The problem addressed by the invention is that of producing a novel synthetic biologically active peptide with immunoregulatory properties of formula X-A-D-Trp-Y, in which A is D-Glu, iD-Glu； X is H or Gly, Ala, Leu, Ile, Val, NVal, Pro, Tyr, Phe, Trp, D-Ala, D-Leu, D-Ile, D-Val, D-NVal, D-Pro, D-Tyr, D-Phe, D-Trp, gamma -aminobutyric acid, xi -aminocaproic acid； Y is Gly, Ala, Leu, Ile, Val, NVal, Pro, Tyr, Phe, Trp, D-Ala, D-Leu, D-Ile, D-Val, D-NVal, D-Pro, D-Tyr, D-Phe, D-Trp, gamma -aminobutyric acid, xi -aminocaproic acid, -OH or substituted amide (C1-C3). The method of producing the peptide involves the synthesis of glutamil-containing peptides in solution by scission of an internal anhydride of tributyloxycarbonyl glutamic (D or L) acid with the appropriate k-salt of D-Trp-Y. This is followed by chromatographic separation of alpha - and gamma -isomers. Further synthesis was carried out by building up a peptide chain using activated esters of tributyloxycarbonyl amino acids.
