Abstract: A process for obtaining 4-hydroxy-2-methyl-N-(2-pyridyl)-2H-1,2-benzothiazine-3-carboxamide 1,1-dioxide, which may be used as a non-steroidal analgesic and anti-inflammatory drug. The process comprises reacting saccharin sodium with isopropyl chloroacetate in dimethylformamide, reacting the resultant isopropyl 3-oxo-1,2-benzoisothiazoline-2-acetate 1,1-dioxide with sodium isopropylate in isopropanol to produce an intermediate which, when methylated in an aqueous-alcoholic basic medium with dimethyl sulfate, gives an intermediate compound which when condensed with 2-aminopyridine in xylene, yields 4-hydroxy-2-methyl-N-(2-pyridyl)-2H-1,2-benzothiazone-3-carboxamide 1,1-dioxide.
Type:
Grant
Filed:
June 24, 1987
Date of Patent:
January 10, 1989
Assignee:
Induspol, S.A.
Inventors:
Jordi Frigola Constansa, Jose M. Ribalta Baro, Julio Campon Pardo