• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:
    The subject of the invention is a process for resolving mixtures of (+)- and (-)-6-methoxy- a-methyl-2- naphthaleneacetic acid into the enantiomers thereof, characterized in that N-methyl-D-glucamine [= 1-deoxy-1-(methylamino)-D- glucitol] is used as the resolving agent, so that the 6-methoxy- α-methyl- 2-naphthaleneacetic acid is converted into the corresponding diastereoisomeric N-methyl-D-glucamine salt pair which, because of very different solubilities, can be separated easily and completely with high yield.
    公开号:SU1029826A3
    申请号:SU792788706
    申请日:1979-07-18
    公开日:1983-07-15
    发明作者:Фелдер Эрнст；Питер Дэйвид；Заттер Ганс
    申请人:Синтекс Корпорейшн (Фирма)；
    IPC主号:
    专利说明:

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    About 1 | The invention relates to a method for separating an optically active isomer, namely (+) -2- (6-methoxy-2-naphthyl) propionic acid from a mixture of {+} and (-) acids. A known method for separating optical active acids by separation mixtures of (+) and (-) acids, for example. 2- (b-methoxy-2-naphthyl) propionic, by the formation of salts with an optically active base, namely cinchonidine, followed by crystallization, while crystallization is carried out in the presence of an inorganic base , HMeraaiero, 8 l. However, ciconidine vg. It is rather expensive alkaloid, which causes the disadvantages of this method. The closest technical substance to the proposed method is the method of separating (+) isomer of 2- (b-methoxy-2-naphthyl) propionic acid from a mixture of (+) and (-) acids or "X salts by forming salts with optically active amines , namely, glucosamines with subsequent fractional recrystallization 2. The disadvantages of this method are the difficulty of obtaining glucosamine itself and the slight difference in solubility of its salts with (+) and (-) acid isomers. The aim of the invention is to increase the selectivity of the process. The goal is achieved by the method of separating (+) - 2- (b-methoxy-2-naphthyl) propionic acid from a mixture of (- () and (-) - 2- {b-methoxy-2-naphthyl) propionic acids or their salts by forming salts with an optically active base in an organic solvent medium at boiling point, in particular at 60-100 ° C, followed by fractional recrystallization, isolation of salt enriched in (+) - acid isomer, and splitting the latter, as optically active bases use N-methyl-O-glucamine, taken in an amount of 50-100 mol. %, based on a mixture of (+) and (-) acids, and acetone, water, lower alcohols or their mixtures are used as a solvent: Mainly SOSO mol% is used. M-methyl-O-glucamine and 50 is 40 mol%. inorganic or organic base, considered, -Mon (4) and (-) acids, selected by the, group of potassium hydroxide, sodium hydroxide and triethylamine. Example 1. N-methyl-O-glucam new salt (, +) -2- (b-methoxy-2-naphthyl) propionic acid. 460.7 g of racemic 2- (b-labels of C-2-naphthyl) propionic acid (2 mol) and 390, (2 mol) of N-methyl-b-glucamine 1-deoxy-1- (methylamino) -D-glucitol 3 dissolved in 4 liters of boiling methanol. The solution is filtered and carefully cooled with slow stirring to 45 ° C. Then, 1 g of {+) - 2- (6-methoxy-2-naphthyl) propionic acid M-methyl-O-glucamine salt crystals (previously prepared by cooling the solution and rubbed with a glass rod, filtering under vacuum and washing with a small amount of methanol /. Immediately after the introduction of the seed, intensive crystallization of the N-methyl-O-glucamine salt of i (+) - 2- (b-methoxy-2-naphthyl) propionic acid begins. The temperature is first maintained at 45 ° C and then slowly reduced to. Drop-down crystals are filtered and washed not a large amount of methanol. Yield: 360 g of N-methyl-β-glucamine salt (+ i) -2- (b-methoxy-2-naphthyl /) in acid and 84% of the theoretical yield. Temperature melting point 15b-158 ° C. Specific rotation at 20 ° C, 1% aqueous solution. 589 degrees -18.59 -22.85 -42.53 -80.63 The resulting product (360 g) is redissolved in 4.4 l of boiling methanol, filter the resulting solution, slowly cool, seed from the same material, cool the mixture, filter and wash the crystals. Yield: 278 g of pure M-methyl-1) -glucamine salt 1 +) -2- (b-methoxy-2-naphthyl} propionic acid, which corresponds to 65% of the theoretical yield. Melting point 160-161 C. Specific rotation at 20C, 1% aqueous solution, degree -20 -23.95 -44.83 -87.19 Calculated,%: C 59.28, 3.29. C21, Found,%: C 59.58, 3.42. The mother liquors are evaporated to dryness to regenerate methanol. The evaporation residue is dissolved in water and the resulting solution is acidified with hydrochloric acid. As a result, (-) - 2 (.b-methoxy-2 -natryl) propionic acid precipitates. Yield: 228 g (-) - 2- ( b-methomsi-i2 - and aftot of pro-pionic acid, which corresponds to 99.1% of the theoretical yield, -Melt temperature 145-146.S. -45.8 1% solution of chloroform 589 - Optical purity: 67 15% The resulting product by racemization can be re-converted into a racemate, i.e., the starting product, and reused in the separation process. Example 2. Re-use of mother liquors. The separation operation was carried out as described in Example 1, using the same amounts of starting materials, but instead of fresh methanol, a methanol mother liquor from previous experience was used. 431 g of N-methyl-1) glucose of a new salt of (+) - 2- (6-methoxy-2-naphthyl) propionic acid are obtained, i.e. 100% of a theoretical yield. Melting point: 155-158 ° C. Specific rotation at 20 ° C, 1% aqueous solution. Wavelength -1.589 degrees -18.52 -21.41 -40.5 -76.6 After recrystallization from 4.4 fresh methanol, 326 g Mm of the tel-3) -glucamine salt (+) -2 are obtained -.6-mztoksi-2 naphthyl propionic acid, yield 76% of the theoretical. Melting point 159-160 C. Specific rotation at 20 ° C, 1% solution in water. Dpine waves 589 degrees -20,02 -24,12 -45,88 -88, the separation of the racemate 2- (6-methoxy -2-naphthyl) propionic acids continue 3 more times using the mother liquor obtained in the previous stage. The material balance of the process is as follows. Used: 2303.5 g of the racemate 2-1.6-methoxy-2-naphthyl) propionic acids. Received: 1613.5 g of N-methyl-C-glucamine salt (+ J-2- 6 methoxy-2-naphthyl) propionic. acids, i.e. 75/8% of theoretical yield, 1120 g (- / - 2- (b-methoxy-2-naphthyl propionic acid, C ° J -47 ± 2f optical purity 69%. Example 3. {+) -2- (6 -methoxy-2-naphthyl propionic acid, 460.7 g (2 mol of 2- (b-methoxy-2-naphthyl) propionic acid racemate, 2) and 390 g of N-methyl-1-glucamine are dissolved in 4 liters of boiling methanol. the stereoisomers are separated according to the method described in Example 1. The result is a .370 g -methyl-B-glucamine salt of (+) - 2- (6-methoxy-2-naphthyl) propionic acid, which is 86.9% from theoretical yield. Melting point 158-159s. -19.1, |: o / J -83.7 ° (in water). 65 Methanol mother liquors are used to extract (-) - 2- (6-methoxy-2-naphthyl) propionic acid and N-methyl-P-glucamine from them. The resulting salt (370 g) is dissolved in 1750 ml of water, heated the solution is up to 80 ° C and filtered. The clear solution is acidified slowly by adding 250 ml of 4N sulfuric acid to it with stirring and at a temperature of 80 ° C. The resulting suspension is cooled to 20 ° C, the product is filtered and washed with water. The mother liquor is collected. The filtered product is washed with acidified 0.001 n. hydrochloric acid to the complete absence of sulfate ions. The result is 196.3 g of (+) -2 - (. 6-methoxy-2-naphthyl) propib-, a new acid, which is 98% of the theoretical yield per salt and 85.16% of the theoretical yield based on the starting racemate. melting point 156-157 ° C, U320 + 65.2 t Content 99.4%. The amount of by-products according to thin layer chromatography is insignificant. The loss on drying 0, the quality of the product, obtained 4 |) by this method (naproXeh), meets (according to the optical rotation value) the requirements imposed on it according to the pharmacopoeia -tdj (+63) - (+ 68.5) (British Pharwocopeia Appendix 75. Example 4. Regeneration of (-) -2- (b-methoxy-2-naphthyl propionic acid (A) and N-methyl-1) -glucamine (B). Regeneration (A). Methanol fluids, obtained after separation of the isomers in accordance with Example 3, are evaporated to dryness. The residue is dissolved in 2300 ml of water at. Acidification of a solution of 290 m of 4N, sulfuric acid, cooling, filtration and drying, carried out analogously to Example 3, gives 255 (-) -2- (b-methoxy-2-naphthylMpropionic acid, which is then racemized in a known manner and returned into the process. The material - Output {+) - and (-) - 2- (b-methoxy. al-Si-2-naphthyl propionic balance of acids, B -, .. w .. "". IP- .H. Source material racemate Regeneration B. Aqueous stock solutions obtained after the isolation of (+) - and (-) - 2-1 6-methoxy 2-naphthyl / propionic acids in Example 3, containing W-methyl-1) -glucamine sulfate and a suspension of calcium hydroxide hydroxide obtained by quenching 63.7 g of calcium oxide (i.e. at the rate of 105% relative to the used sulfuric acid) is combined and slowly added (250 ml of water). As a result, calcium sulfate is formed. Most of which precipitates, it is filtered and washed with water. The filtrate is concentrated to a small volume, the precipitated calcium sulphate is filtered off and washed with a small amount of water. The filtrate is again concentrated by evaporation in vacuo at 85-95 ° C. Dry. The residue after evaporation is dissolved in 2400 ml of boiling 95% ethanol under reflux, the hot solution is filtered and then cooled to 15 ° C. As a result, H-methyl-1) -glucamine crystals precipitate. The amount of N-methyl-D-glucamine obtained is 351 g. Yield: 90% of theory. The content of M-methyl-0-glucamine in the resulting product is 99%. Melting point 127-128C Id -1b, 95 Example 5. Regeneration of Nm thyl-1) -glucamine with an amino acid resin. To decompose N -methyl-D) -gluck of mine salts of (+) - and (-) - 2 (b -met Si-2-naphtyJ propionic acids and precipitate (+) - and (-} - 2- (b- -2-naphthyl) propionic acid can also be used instead of sulfuric acid, as in the case of examples 3 and 4 (, A), hydrochloric acid. Then the hydrochloride of N-methyl-B-glucamine remains dissolved in the aqueous phase , from which chlorine ions are much more easily than sulphate ions, can be removed using an ion exchange resin. Master solutions obtained as a result of precipitation (. +) - T (-) - 2- (b-methoxy-2-naphthyl propionic acid) when processing 2 mol of the starting racemate and containing N-methyjjI-l-glucumin hydrochloride, the lot is neutralized with ammonia, to pH 7 and then passed through a column with 1.6 l Atnberlit nR-120 ion-exchange resin, after which the ion-exchange resin is passed through 3.2 l deionized water. The effluent solution containing chlorine ions is removed. H-Methyl-b-glucamine is washed out of the ion exchange resin, passing through it 2400 ml of an aqueous solution of ammonia (2.5 VI) and 3.2 l of deionized water. The resulting solutions are combined and concentrated by evaporation to dryness. The residue after evaporation is recrystallized, as described in example 4, from 2400 ml of 95% ethanol. The result is 351 g of N-methyl-ZZ-glucamine. Yield: 90%. The content of N-methyl-C) -glucamine in the resulting product is 99.1%. Melting point 127-128 C. Ceil, 0 -17 Example 6. 4.6 g of d1 2 - (, 6-methoxy-2-naphthyl) propionic acid are heated with 1.01 g of triethylamine 0.5 equivalent in 20 ml of 6% a solution of toluene in methanol to the refluxing temperature of the solvent; a refrigerator for dissolving d 2- (6-methoxy-2-naphthyl propionic acid. To the resulting solution, add 1.95 g of H-methyl-1) -glucamine, 0 , 5 equivalents) and cool it to room temperature (approximately 20-23 seconds). The result is 3.52 g of a product enriched in N-methyl-P-glucamine salt of (+) 2- (6 methoxy-2-naphthyl) propionic acid), which is then dissolved in 25 ml of water, treated with hydrochloric acid to acidity, in which crystals of a product enriched in (+) 2- (b-methoxy-2-naphthyl) propionic acid fall out of solution. The crystals are separated by filtering hell + 48.8 °. 1.00 g of a product enriched with AND-methyl-P-glucamine salt +) 2- (6-- etoxy-2-naphthyl propionic acid, recrystallized from 10 ml of methanol and 20 ml of ethanol, the solution is concentrated, and 5 ml of solvent are distilled , and cooled. The result is 0.85 g of recrystallized salt, which is treated with hydrochloric acid as described.
    权利要求:
    Claims (2)
    [1]
    1. METHOD FOR ISOLATING (+) - 2- (6 7- METHOXY-2'-NAPHTHyl) PROPIONIC ACID from a mixture of (+) and (-) - 2- (b-methoxy-2'-naphthyl) propionic acids or their salts by the formation of salts with an optically active base in an organic solvent at boiling point, in particular at 60-100 ° C, followed by fractional crystallization, isolation, salt enriched in (+) - acid isomer, and splitting of the latter, about t and wherein, in order to improve the selectivity of the process, N.-methyl-O-glucamine taken an amount of 50 100 mol. %, counting on a mixture of (+) and (-) acids, and acetone, water, lower alcohols · C 1 -Cp, or mixtures thereof are used as a solvent.
    [2]
    2. The method of pop. 1, characterized in that use 50 to 60 mol.% N-methyl-D-glucamine and 50
    40 mol.% Inorganic or organic bases, counting on a mixture of (+) yi (-) acids selected from the group of potassium hydroxide, sodium hydroxide-:
    aria and triethylamine.
    1,029,826 A ί
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    优先权:
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