http://rdf.ncbi.nlm.nih.gov/pubchem/patent/GB-772799-A
Outgoing Links
| Predicate | Object |
|---|---|
| assignee | http://rdf.ncbi.nlm.nih.gov/pubchem/patentassignee/MD5_fdc7409a7738c5227127c590cb253dbc |
| classificationCPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C07J5-00 http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C07J75-00 |
| classificationIPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C07J5-00 http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C07J75-00 |
| filingDate | 1953-03-05-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationDate | 1957-04-17-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationNumber | GB-772799-A |
| titleOfInvention | Cyclopentanophenanthrene derivatives and a method for the preparation thereof |
| abstract | The invention comprises D 1-allopregnene-11a :21 - diol - 3:20 - dione, D 1,4-pregnadiene - 11a :21-diol-3:20-dione, their 21- and 11:21 - esters and D 4-pregnene - 11a :21 - diol - 3:20 - dione. The D 1-allopregnene and D 1,4-pregnadiene compounds are prepared from the corresponding allopregnane-11a :21-diol-3:20-dione or appropriate ester by mono- or di-bromination, yielding the 2-bromo- and 2:4-dibromo derivative respectively, which are then dehydrobrominated. The D 4-pregnene compounds are prepared from the corresponding allopregnanes by dibromination to form the 2:4-bromo derivative, and then treatment with sodium iodide in the presence of a lower aliphatic ketone to yield the corresponding 2-iodo-D 4-pregnene which is finally treated with a deiodinating agent, e.g. chromous chloride, sodium bisulphite, Raney nickel or a tertiary amine. In examples: (1) allopregnane-11a :21-diol-3:20-dione diacetate is monobrominated in glacial acetic acid to yield 2-bromo-allopregnane-11a :21-diol-3:20-dione diacetate which is then dehydrobrominated with collidine or 2:6-lutidine to D 1-allopregnene - 11a :21 - diol - 3:20 - dione diacetate. Saponification with ethanolic potassium hydroxide gives the parent diol, which is then mono-esterified to the 21-acetate. (2) 2-Bromoallopregnane - 11a :21 - diol - 3:20 - dione diacetate is treated with semicarbazide hydrochloride or 2:4-dinitrophenylhydrazine and the resulting carbonyl derivative reacted with pyruvic acid to give D 1-allopregnene-11a :21 - diol - 3:20-dione diacetate. (3) Allopregnane-11a :21-diol-3:20-dione diacetate is dibrominated and the product treated with collidine to give D 1,4-pregnadiene-11a :21-diol-3:20-dione diacetate, which is then saponified and monoesterified to the 21-acetate as in (1). (4) 2:4-Dibromo-allopregnane-11a :21-diol-3:20-dione diacetate is refluxed with sodium iodide in acetone, and the resulting D 4-pregnen-2-iodo-11a :21-diol-3:20-dione diacetate reduced with collidine or chromous chloride to D 4-pregnene-11a :21-diol-3:20-dione diacetate, which is saponified and reacetylated to the 21-mono-acetate as in (1). Specifications 693,991 and 746,953 are referred to. |
| priorityDate | 1952-03-07-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| type | http://data.epo.org/linked-data/def/patent/Publication |
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Total number of triples: 41.