http://rdf.ncbi.nlm.nih.gov/pubchem/patent/CN-109060473-B
Outgoing Links
| Predicate | Object |
|---|---|
| classificationCPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/G01N30-06 http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/G01N1-28 |
| classificationIPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/G01N30-06 http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/G01N1-28 |
| filingDate | 2018-07-27-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| grantDate | 2021-03-05-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationDate | 2021-03-05-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationNumber | CN-109060473-B |
| titleOfInvention | Preparation method of ambroxol hydrochloride impurity reference substance |
| abstract | The invention discloses a preparation method of an ambroxol hydrochloride impurity reference substance, which comprises the following steps: firstly, dissolving ambroxol hydrochloride into a proper amount of dichloromethane solution, then adding a certain amount of sodium bicarbonate aqueous solution, uniformly stirring to obtain free ambroxol, separating an organic phase, drying, concentrating, dissolving a concentrated solution into an alcohol solution, then refluxing with excessive orthoformate, condensing to obtain a (1R, 4R) -4- (6, 8-dibromo-3, 4-dihydroquinazoline) -cyclohexanol crude product, and purifying the crude product by silica gel column chromatography to obtain a pure product. The orthoformate is creatively applied as the condensing agent, and compared with condensing agents reported in other documents, the orthoformate has the advantages of good stability, high safety, low cost, high product yield, easiness in purification and the like. |
| priorityDate | 2018-07-27-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| type | http://data.epo.org/linked-data/def/patent/Publication |
Incoming Links
Total number of triples: 38.