Process for the preparation of oxazinobenzothiazine 6,6-dioxide derivatives
US4797482A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 15, 1987 |
| Grant date | Jan 10, 1989 |
| Priority date | — |
| Expiry date | Apr 15, 2007 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D513/04
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
The present invention relates to a process for the preparation of a 5-methyl-3-heteroaryl-2H,5H-1,3-oxazino[5,6-c] [1,2] benzothiazine-2,4-(3H)-dione 6,6-dioxide of the general formula I: ##STR1## in which R represents a heteroraryl radical, preferably substituted or unsubstituted pyrimidinyl or pyridyl, of the type consisting in reacting an amide of the general formula II: ##STR2## in which R.sup.1 represents a heteroarylamino radical, preferably substituted or unsubstituted pyrimidinylamino or pyridylamino, with a compound of the general formula III: ##STR3## in which R.sup.2 represents a C.sub.1 to C.sub.4 lower alkyl radical such as methyl or ethyl, an aryl radical such as phenyl, or an alkylaryl radical such as benzyl, wherein the reaction is carried out in an organic solvent selected from the group comprising pyridine, substituted pyridines such as 4-dimethylaminopyridine, 4-(pyrrolidin-1-yl)pyridine and 2,6-ditert.-butyl-4-methylpyridine, and mixtures thereof.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.