http://rdf.ncbi.nlm.nih.gov/pubchem/patent/ES-2656239-T3
Outgoing Links
| Predicate | Object |
|---|---|
| assignee | http://rdf.ncbi.nlm.nih.gov/pubchem/patentassignee/MD5_b2f3e517f7324a7e38ef03b58b029124 |
| classificationCPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C07D207-273 |
| classificationIPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C07D207-273 |
| filingDate | 2012-04-24-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| grantDate | 2018-02-26-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| inventor | http://rdf.ncbi.nlm.nih.gov/pubchem/patentinventor/MD5_95f7fac128bffbd1d7ed7925da6aaea6 |
| publicationDate | 2018-02-26-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationNumber | ES-2656239-T3 |
| titleOfInvention | Method of preparation of the crystalline form I of the 4-hydroxide-2-oxo-1-pyrrolidine-acetamide racemate |
| abstract | A method of preparing the crystalline form I of the 4-hydroxy-2-oxo-1-pyrrolidine acetamide (oxiracetam) racemate comprising the following steps: (1) dissolving raw oxiracetam in isopropyl alcohol to achieve supersaturation; (2) heat and stir for 7 h at 38-42 ° C to obtain a suspended sediment; (3) filter and dry to obtain a crystal; wherein said crystalline form I has diffraction peaks that appear at the following diffraction angles 2θ: 12,011, 15,318, 17,407, 19,633, 21,228, 22,052, 24,577, 25,223, 27,647, 28,161, 29,109, 30,805, 31,276, 31,766, 32 , 77, 33,477, 35,252, 35,645, 36,236, 37,379, 39.56, 40,489, 41,256, 41,948, 43,443 and 44,628; wherein said crude oxiracetam is synthesized by the following steps: (a) 139.6 g of glycine ethyl ester hydrochloride were added to 1100 ml of anhydrous ether, cooled to -6 ° C, and then introduced 27 , 2 g of ammonia gas to form free glycine ethyl ester from glycine ethyl ester hydrochloride, in which glycine ethyl ester hydrochloride: anhydrous ether: ammonia gas> = 1 mol: 1100 ml: 1.6 mol; (b) 336 ml of anhydrous alcohol and 67.2 g of sodium bicarbonate were added to the above mixture, followed by the addition of 166.6 g of ethyl 4-chloro-3-hydroxybutyrate in drops; the period for the dropwise addition lasted a time of 1.8 h, and then the reaction continued for 22 h at a temperature of 72 ° C and pH> = 8; (c) the above reaction solution was filtered, and the residue was washed thoroughly with ethanol and the filtrate was concentrated; The concentrate was dissolved in water and extracted by adding ethyl acetate 7 times the weight of the filtrate; the aqueous phase was concentrated and separated by column chromatography; finally, 23% by weight aqueous ammonia was added and then the reaction continued for 4 h at 22 ° C to obtain crude oxiracetam, in which the amount of 23% by weight aqueous ammonia is 13 times the weight of the product separated by column chromatography; wherein the glycine ethyl ester: sodium bicarbonate: ethyl 4-chloro-3-hydroxybututorate> = 1: 0.8: 1 mol, the amount of anhydrous alcohol is 5 times the weight of sodium bicarbonate; (d) the crude product obtained above was dissolved in water, treated with strong acid cation exchange resin 732, and then neutralized with strong base anion exchange resin 711; the solution was collected and concentrated; wherein the crude product: water> = 1 g: 0.5 ml, the crude product: the strong acid cation exchange resin> = 1 g: 10 ml. |
| priorityDate | 2011-08-11-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| type | http://data.epo.org/linked-data/def/patent/Publication |
Incoming Links
Total number of triples: 37.