METHOD FOR PRODUCING 2-O-ALPHA-D-GLUCOSYL-L-ASCORBIC ACID ANHYDROUS CRYSTAL-CONTAINING POWDER Russian patent published in 2016 - IPC C07H17/04 A61K31/7048 

FIELD: chemistry.

SUBSTANCE: present invention relates to a method for preparing a composition in form of particles, containing anhydrous crystalline 2-glucoside ascorbic acid, and can be used in pharmaceutical industry. Proposed method comprises allowing cyclomaltodextrin glucanotransferase to act on a solution, comprising either liquefied starch or dextrin and L-ascorbic acid as materials, and then allowing a glucoamylase to act on resulting solution to obtain a solution, containing 2-O-α-D-glucosyl-L-ascorbic acid, with 2-O-α-D-glucosyl-L-ascorbic acid production yield of at least 27 wt%; purification of obtained solution, containing 2-O-α-D-glucosyl-L-ascorbic acid, to obtain content of 2-O-α-D-glucosyl-L-ascorbic acid of more than 86 wt%, in terms of dry weight of solid substance; precipitation of anhydrous crystalline 2-O-α-D-glucosyl-L-ascorbic acid from purified solution with content of 2-O-α-D-glucosyl-L-ascorbic acid of more than 86 wt%, in terms of dry weight of solid substance, by method of controlled cooling or by pseudo-controlled cooling; collection of precipitated anhydrous crystalline 2-O-α-D-glucosyl-L-ascorbic acid and ageing, drying and optionally milling collected anhydrous crystalline 2-O-α-D-glucosyl-L-ascorbic acid without dissolution and recrystallisation to produce a composition in form of particles, containing anhydrous crystalline 2-O-α-D-glucosyl-L-ascorbic acid, which contains 2-O-α-D-glucosyl-L-ascorbic acid in an amount in terms of dry weight of solid substance, of more than 98.0 wt%, but less than 99.9 wt% has crystallinity of anhydrous crystalline 2-O-α-D-glucosyl-L-ascorbic acid at least 90%, when calculating based on x-ray powder diffraction profile of composition in form of particles; where method of controlled cooling is a method of cooling, where temperature T of solution at a time t is expressed by formula T=T₀-(T₀-T_f)(t/τ)³, where τ is operating time, set for crystallisation stage, T₀ is temperature of solution at beginning of crystallisation, and T_f is target temperature after crystallisation; and where pseudocontrolled cooling method is a method of cooling, where liquid temperature T is given linearly or gradually decreases relative to time t, so that (t₀-T_m) is at least 5 %, but less than 50 % of total temperature change (T₀-T_f), where T_m is liquid temperature at moment of time t=τ/2.

EFFECT: method enables to obtain a product which is considerably harder to cake.

7 cl, 10 tbl, 8 ex, 6 dwg