METHOD OF SYNTHESIS AND/OR PURIFICATION OF CLAVULANIC ACID OR ITS PHARMACEUTICALLY ACCEPTABLE SALT OR ESTER AND METHOD OF ITS SEPARATION FROM IMPURITY OF CLAVAM-2-CARBOXYLIC ACID CONTAINING IN FILTERED OFF FERMENTATION BROTH Russian patent published in 2001 - IPC

FIELD: organic chemistry, pharmacy. SUBSTANCE: invention relates to method of synthesis and/or purification of clavulanic acid or its pharmaceutically acceptable salt or ester that involves the following stages: addition of additional solvent taken among -C₁-C₆-alcohols and their mixtures to clavulanic acid solution and water-nonmixable solvent; contact of solution with amine of the formula (I) where R_1,R_2,R_3,R₄ mean independently hydrogen atom, linear or branched C₁-C₈-alkyl, C₂-C_4,- hydroxyalkyl or groups NR₁R₂ and NR₃R₄ in common mean heterocyclic group containing 3-6 methylene groups possibly substituted with oxygen, sulfur atom or imino-group; R₅ means hydrogen atom or methyl group; n is a whole number 1-3; isolation of formed clavulanic acid amine salt; and conversion of amine salt to clavulanic acid or its pharmaceutically acceptable salt or ester. Invention relates to also method of separation of clavulanic acid or its pharmaceutically acceptable salt or ester from impurity of clavam-2-carboxylic acid containing in filtered off broth using stages described above. EFFECT: new and simplified method of synthesis. 10 cl, 11 tbl, 15 ex