CYCLIC PEPTIDES OR THEIR PHARMACEUTICALLY ACCEPTABLE SALTS, A METHOD OF THEIR SYNTHESIS Russian patent published in 1997 - IPC

FIELD: chemistry of peptides. SUBSTANCE: products: cyclic peptides of theformula(I):X-R₁-R₂-Asp-Val-R₆-Thr-R₈-Asn-R₁₀-Thr-R₁₂-Leu-Arg-Lys-R₁₆-Ala- -R₁₉-Lys- where: R₁ - His, N-CH₃-Ala; R₂ - Ala, Ser; R₆ - group: -NH-C(Q)-C(O)- where: Q - (lower) alkylaryl being aryl can be free or substituted in ring with one or some substituents taken from: OH, OCH₃, F, Cl, J, ; R₈ - Asp, Ala, Glu; R₁₀ - Tyr that is free or substituted with lower alkoxy-group; or R₆ where Q - (lower)-alkylphenyl; R₁₂ - Arg, Lys or Orn; R₁₆ - Ala or Gln; R₁₇ - Nle or Ala; R₁₉ - Ala or Val; R₂₂ - Tyr or R₆ where Q - (lower) alkylphenyl; R₂₄ - Ala or Asn; R₂₆ - Ile, Val, Leu; R₂₇ - Lys or Leu; R₂₈ - Asn, Thr, Lys; X - hydrogen or acyl; Y - NH₂, OH or R₂₉-R₃₀-R₃₁ - Z where Z - NH₂; R₂₉ - Gly or Ala; R₃₀ - Gly or Ala; R₃₁ - Met, Cys (Asm), Ala, Thr, or their pharmaceutically acceptable salts. Method of synthesis of peptides (I) involves making peptide chain by solid-phase method on polymeric carrier, splitting off protective groups to obtain amino-group with free by-side chain at the corresponding positions that is necessary for formation of cyclic covalent linkage between these protective groups, splitting off protective groups and polymer-carrier by treatment with the corresponding reagent and if necessary in the presence of so additions as cation acceptors. The synthesized compounds show broncholytic effect and used in medicine. EFFECT: improved method of synthesis. 57 cl, 6 tbl