CS231550B1 - Process for preparing crystalline ß-escin - Google Patents

Abstract

Method for preparing crystalline Jhescine. The aim of the invention is to improve the isolation during the purification of crude /3-escine. The above-mentioned fichel is achieved by preparing /3-escine in such a crystalline form that is technologically advantageously processable — the procedure is that the solution of /3-escine in methanol, after mixing with activated carbon and filtration, is adjusted so that the concentration of /3-escine is 0.111 to 0.273 (expressed as a mass fraction), is heated to a temperature of 40 to 50 ° C, water heated to a temperature of 40 to 50 ° C is added, in an amount of 1.1 to 1.95 parts by weight per 1 part by weight of methanol, the solution is stirred and allowed to crystallize. Field of application — pharmaceutical industry.

Description

231550

The invention relates to a process for the preparation of crystalline 3-escin.

In isolation of β-escin from seeds of Pagan-Tanzania (e.g., NDR 11178, U.S. Pat. No. 1125117, 2339760, 2530941, French Pat. No. 7724689), the most primordial p-escin is obtained, which has to undergo further The most effective way to complicate [3-escin] is to crystallize by prior removal of organic pigments by adsorption to actively charcoal and subsequent filtration, using the procedure of 1 part / 3-escin to prepare crystalline i-escin (Pat. No. NDR 11178). in a 10-fold amount of methanol, the mixture was refluxed, and twice the amount of water heated to 90 ° C was added at 88-90 ° C. According to this procedure, the anise was obtained with crystalline (3-escin) but in an unsuitable crystalline form. so that the further processing of the obtained suspension is time and energy intensive.

The drawbacks of the prior art have been eliminated by the process of the invention, in which the crude (3-escin) is dissolved in methanol, the solution is mixed with activated carbon, filtered, and the filtrate containing 0.111-0.273 (expressed by mass fraction) 3-escin in methanol heated to 40-60 ° C, add water heated to 40-60 ° C in an amount of 1.1-1.95 parts by weight to 1 part by weight methanol, mix and allow to crystallize if Table 1 destroying the amount of water in admixture with methanol, obtaining larger crystals / 3-escin; These crystals are quickly filtered off! from crystallization liners. Conversely, by increasing the amount of water in the crystallization (3-esters from the mixture of methanol - water), smaller crystals are obtained, at a methanol: water ratio of 1: 3.13, a fine suspension passing through a filter having a pore diameter of 20 to 40 µg. This suspension had a sedimentation degree (sedimentation volume = 100 x 100 volume / total volume of the slurry) of 11.8 (Table 1). in which the sedimentation step increases over time, since such suspensions are very fine and poorly filtered, most preferably the suspension of large crystals does not drop sharply depending on the sedimentation time (Tables 1 to 3), extreme cases of crystallization / 3-escin from methanol - water 1: 0.0625, where such a large crystal suspension density was obtained that no sedimentation volume was determined - but in this case, the crystal size was higher than the crystallization yield, and in the present invention the concentration of [beta] -cin in methanol as well as methanol - water is optimally both of the processability of suspensions and of the overall crystallization yield.

Degree of sedimentation / 3-escin versus sedimentation time; suspension / 3-escin in crystallization liquors.

Initial concentration of 3-escin 0.111 (w / w) in methanol, crystallization from methanol-water 1: A (weight ratio), temperature 45 ° CA sedimentation time (min) yield 5 10 15 30 60 crystallization (%) 3.13 0 0 2.9 5.3 11.8 89.46 2.50 20.7 25.5 29.3 33.0 35.5 88.83 1.875 37.8 39.4 40.3 41, 5 46.1 88.23 1.250 82.9 77.2 75.1 75.0 74.7 86.50 0.625 thick suspension, does not settle 66.40

Table 2

Degree of sedimentation / 3-escin versus sedimentation time. Baseline concentration of 3-escin 0.200 (w / w) in methanol; crystallization zotanol - water 1: A (weight ratio), temperature 45 ° C mixture crystallization yield (%) A 5 sedimentation time (min) 10 15 30 60 3,75 0 0 0 0 0 3,13 0 0 5, 9 8.5 11.8 2.50 82.8 68.9 59.7 59.3 58.9 87.6 1.875 73.4 61.4 59.3 58.9 58.9 87.3 1.250 92 6 77.6 75.3 73.7 73.7 86.3

Claims (1)

SUBJECT A process for the preparation of crystalline β-escin, well filterable, from crude β-escin after dissolution in methanol, mixing with activated carbon and filtration, characterized in that to a solution of? S-escin in methanol at a concentration of 0.111 to 0.273 expressed BACKGROUND OF THE INVENTION weight fractions heated to 40 to 50 ° C are added water heated to 40 to 50 ° C in an amount of 1.1 to 1.95 parts by weight per 1 part by weight of methanol, mixed and allowed to crystallize.