| Predicate |
Object |
| assignee |
http://rdf.ncbi.nlm.nih.gov/pubchem/patentassignee/MD5_e0f4f8190960626ec922a1f03bcd4aba |
| classificationCPCInventive |
http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C07D501-00
http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C07D205-095 |
| classificationIPCInventive |
http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C07D205-095
http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C07D501-00 |
| filingDate |
1990-03-07^^<http://www.w3.org/2001/XMLSchema#date> |
| grantDate |
1991-12-03^^<http://www.w3.org/2001/XMLSchema#date> |
| inventor |
http://rdf.ncbi.nlm.nih.gov/pubchem/patentinventor/MD5_d4349dd2f955814bfd9180dfaf6c552f
http://rdf.ncbi.nlm.nih.gov/pubchem/patentinventor/MD5_bb3d3ea234cac708940f091a94876be2
http://rdf.ncbi.nlm.nih.gov/pubchem/patentinventor/MD5_79d55265dc7af466d9bdd78a3586b81f
http://rdf.ncbi.nlm.nih.gov/pubchem/patentinventor/MD5_7b61de268792e8c5df9df280841523fc |
| publicationDate |
1991-12-03^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationNumber |
US-5070195-A |
| titleOfInvention |
Ring-opening process for preparation of 2-chlorosulfinyl azetidinones |
| abstract |
An improved method for preparing 2-chlorosulfinyl azetidine-4-one comprises heating a penicillin sulfoxide ester with an N-chlorohalogenating agent at a temperature of about 75° C. to about 140° in an inert organic solvent, and in the presence of an organic solvent insoluble, strongly basic ion exchange resin. Desirably, the ion exchange resin comprises a styrene-divinyl benzane copolymer which is about 2 to 16% cross-linked and incorporates a quaternary ammonium functionality. Such ion exchange resins are commercially available. The 2-chlorosulfinyl azetidine-4-one which is produced by this method can be cyclized in the presence of a Friedel-Crafts catalysts to afford the 3-exomethylene cepham sulfoxide ester in yields of 80-90%. |
| isCitedBy |
http://rdf.ncbi.nlm.nih.gov/pubchem/patent/EP-0659742-A1
http://rdf.ncbi.nlm.nih.gov/pubchem/patent/US-5578721-A
http://rdf.ncbi.nlm.nih.gov/pubchem/patent/US-5604222-A
http://rdf.ncbi.nlm.nih.gov/pubchem/patent/US-5347000-A |
| priorityDate |
1989-11-06^^<http://www.w3.org/2001/XMLSchema#date> |
| type |
http://data.epo.org/linked-data/def/patent/Publication |