摘要 |
FIELD: chemistry. ^ SUBSTANCE: invention relates to a peptide copolymer containing lysine, alanine, tyrosine and glutaminic acid residues in ratio of 0.4-0.45:0.3-0.36:0.09-0.11:0.14-0.18, including its acid addition salt - acetate, and having average molecular weight in the interval 8.7-14.5 kDa, which can be used in a pharmaceutical composition for preparing a medicinal agent against multiple sclerosis, particularly medicinal agent Glatiramer acetate. The peptide copolymer is obtained through copolymerisation of N-carboxyanhydride of N-trifluoroacetyl-L-lysine and/or N-carboxyanhydride of N-benzyloxycarbonyl-L-lysine with N-carboxyanhydrides of L-alanine, gamma-O-benzyl-L-glutaminic acid and L-tyrosine with an initiator diethylamine in a medium of aprotic solvents dioxane or tetrahydrofuran or mixtures thereof. Benzyl type protective groups are removed from lysine and glutaminic acid residues using a solution of hydrogen bromide in acetic acid with a catalytic amount of water, and volatile amines diethylamine or methylamine in form of their aqueous solution are used to remove protective trifluoroacetyl groups from lysine residues. ^ EFFECT: method enables control of such properties of the product as average molecular weight and amino acid composition. ^ 3 cl, 7 ex |