http://rdf.ncbi.nlm.nih.gov/pubchem/patent/GB-719103-A
Outgoing Links
| Predicate | Object |
|---|---|
| assignee | http://rdf.ncbi.nlm.nih.gov/pubchem/patentassignee/MD5_37f4922dfb7777b019e504b885211b8e |
| classificationCPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C07C231-02 http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C07C231-12 |
| filingDate | 1952-03-11-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationDate | 1954-11-24-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationNumber | GB-719103-A |
| titleOfInvention | 2-acylamino-1-aryl-propane-1,3-diols |
| abstract | 2 - Acylamino - 1 - arylpropane-1 : 3 - diols of the general formula <FORM:0719103/IV (b)/1> (wherein R represents an aryl radical substituted by at least one nitro group and R1 represents an alkyl or aryl radical, which may be substituted) are manufactured by selective reduction, with lithium aluminium hydride, of the carboxylic ester group of an oxazoline of the general formula <FORM:0719103/IV (b)/2> (wherein R11 represents an alkyl radical), by introducing an anhydrous ether solution of lithium aluminium hydride in a practically stoichiometric amount into a solution of the oxazoline while maintaining the temperature around 0 DEG C. and stirring thoroughly, followed by acid hydrolysis of the reduction product to decompose the organo-alumino-lithic complex and open the oxazoline ring. The stoichiometric amount of lithium aluminium hydride is 0.5 mol. per mol. of oxazoline when R1 is alkyl and 0.75 mol. when R1 is aryl, when loss of hydrogen occurs. The hydrolysis may be effected in a single step using a weak acid, or in two stages using first an anhydrous strong acid to produce a 4-hydroxymethyloxazoline salt which is then further hydrolysed with an aqueous solution of sodium acetate. In examples: (1) a solution of trans-2-phenyl-5-p-nitrophenyl-4-carbethoxyoxazoline in ether is stirred at 0 DEG C. while an ethereal solution of lithium aluminium hydride is poured in, and the product is hydrolysed to DL-threo-2-benzamido-1-p-nitrophenylpropane-1 : 3-diol by either (a) passing in hydrogen chloride, collecting the precipitated trans - 2 - phenyl - 5 - p - nitrophenyl - 4 - hydroxymethyloxazoline hydrochloride and heating it with sodium acetate solution, or (b) adding aqueous acetic acid and allowing the mixture to stand; (2) a solution of trans-2-methyl - 5 - p - nitrophenyl - 4 - carbethoxyoxazoline in ether and benzene is treated as in 1 (b) to produce DL-threo-2-acetamido-1-p-nitrophenylpropane - 1 : 3 - diol; (3) a solution of trans - 2 - dichloromethyl - 5 - p - nitrophenyl-4-carbethoxyoxazoline in ether and tetrahydrofuran is treated with lithium aluminium hydride as in (1) and the product hydrolysed with dilute aqueous methanolic formic acid to DL-threo-2-dichloroacetamido-1 - p - nitrophenylpropane - 1 : 3 - diol; (4) the corresponding L-trans-oxazoline similarly yields chloramphenicol. Trans - 2 - phenyl - 5 - p - nitrophenyl - 4 - carbethoxyoxazoline is obtainable by condensing ethyl benzimidate with the hydrochloride of ethyl threo-p-nitrophenylserinate, or the hydrochloride of ethyl benzimidate with ethyl threo-p-nitrophenylserinate. Trans-2-methyl- and trans- and L-trans-2-dichloromethyl - 5 - p - nitrophenyl - 4 - carbethoxyoxazolines are obtainable in an analogous manner or by nitration of the corresponding 5-phenyl compounds. |
| priorityDate | 1951-03-13-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| type | http://data.epo.org/linked-data/def/patent/Publication |
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