ADDITIVES AS POLYALKYLENE GLYCOLIC ACID Russian patent published in 2008 - IPC C08G65/332 A61K47/48 

FIELD: organic chemistry, pharmacy.

SUBSTANCE: invention relates to polyalkylene glycolic acids and their binding with therapeutically effective biopharmaceutical preparations, such as polypeptides, sugars, proteins and therapeutically active low-molecular compounds in aims for preparing therapeutically active conjugates of polyalkylene glycol with indicated biopharmaceutical preparations. Invention claims compounds of general formulae (I-A) and (I-B) wherein X means -NH-, and compounds of the general formula (I-C) wherein X means -O- or -NH-. Also, invention claims methods for synthesis of these compounds that involve the condensation reaction of compound of the formula: RO-PAG-V (for compounds of formulae (I-A) and (I-B)) or compound of the formula: RO-PAG¹-O-(CH₂)_k-V (for compound of the formula (I-C)) wherein V means -OH or -NH₂ with corresponding halide, hydrolysis of prepared ester to form a corresponding acid and, if necessary, interaction of indicated free acid with halogen in an activated leaving group in the presence of a condensing agent to form indicated activated ester. Also, invention claims conjugates of the general formula that are given in the invention description. Indicated reagents show enhanced stability in aqueous medium and they can be used for site-specific modification of protein. Claimed compounds possess higher activity and prolonged biochemical half-life index.

EFFECT: improved method of synthesis, valuable properties of additives.

19 cl, 9 ex