http://rdf.ncbi.nlm.nih.gov/pubchem/patent/GB-715581-A
Outgoing Links
| Predicate | Object |
|---|---|
| assignee | http://rdf.ncbi.nlm.nih.gov/pubchem/patentassignee/MD5_af99df08b153738cd418446a75d09bfc |
| classificationCPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C07D209-20 |
| classificationIPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C07D209-20 |
| filingDate | 1952-08-21-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationDate | 1954-09-15-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationNumber | GB-715581-A |
| titleOfInvention | Preparation of dl-tryptophan and its n-acyl derivatives |
| abstract | A method for making dl-tryptophan and N-acyl-tryptophan comprises saponifying and decarboxylating a dialkyl ester of an acylamido-(3-indolyl-methyl) malonic acid solely by means of heat and alkali, the saponification and decarboxylation step consisting in mixing and heating the said ester with from 1.3 to 2.5 equivalent weights of an alkali for each mol. of the ester, in an aqueous medium, under pressure, at a temperature between 150 DEG and 300 DEG C. The nature of the product (i.e. tryptophan or its N-acyl derivative) depends on the reaction conditions; e.g. at 175 DEG C. the N-acyl derivative is first obtained and may be isolated or converted by heating with additional alkali (2 or more equivalents) at say 100-175 DEG C. to tryptophan. At 250 DEG to 300 DEG C. and using 2.0 to 2.5 or more equivalents of alkali, the initial acylamido ester is converted to tryptophan directly. In an example, one molecular proportion of diethyl acetamido-(3-indolylmethyl) malonate is heated with 2.2 equivalents of sodium hydroxide at 175 DEG C. under pressure. After cooling, 2.8 equivalents of alkali are added to the N-acetyl dl-tryptophan obtained and heating at 175 DEG C. resumed, yielding dl-tryptophan. A table illustrates the effect on the yield of tryptophan of varying the initial amount of alkali between 3.0 and 1.3 mols. of alkali per mol. of ester, at 170-175 DEG C., 2 mols. of alkali being used in each case in the second stage. In a second table the product of a series of single stage processes is analysed for tryptophan and N-acetyl-tryptophan content, reaction temperatures between 170 DEG and 300 DEG C. and reaction times between 1.5 hours and 1 minute being employed. Other suitable alkalis are potassium, lithium, calcium and barium hydroxides. Specification 599,046 is referred to. |
| priorityDate | 1951-09-08-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| type | http://data.epo.org/linked-data/def/patent/Publication |
Incoming Links
Total number of triples: 30.