Process and intermediates for production of benzothiazine carboxamides
AssigneePfizer Inc.
InventorJoseph A. Kardys
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Abstract
A novel compound of the formula ##STR1## wherein R is hydrogen, benzyl or (C.sub.1 -C.sub.3)alkyl; R.sup.1 is benzyl or (C.sub.1 -C.sub.4)alkyl and Z.sup.1 taken together with --C.dbd.N-- forms a heterocyclic group Z where Z is 2-pyridyl, alkyl substituted-2-pyridyl, 2-thiazolyl, 2-thiazolyl substituted by one or two alkyl groups or 5-alkyl-3-isoxazolyl, each alkyl having from one to four carbon atoms; and a novel process employing the above compounds as intermediates for production of known anti-inflammatory agents of the formula ##STR2##
Claims11
A process for production of a 3,4-dihydro-2H-1,2-benzothiazine-3-carboxamide-1,1-dioxide of the formula ##STR22## wherein R is hydrogen, benzyl or alkyl having from one to three carbon atoms;
- and Z is 2-pyridyl, alkyl substituted-2-pyridyl, 2-thiazolyl, 2-thiazolyl substituted by one or two alkyl groups, or 5-alkyl-3-isoxazolyl, each alkyl having from one to four carbon atoms;
- which comprises the steps of:
- (a) contacting an ester of the formula ##STR23## wherein R.sup.1 is benzyl or alkyl having from one to four carbon atoms, with an amine of the formula ZNH.sub.2 in the presence of reaction inert organic solvent at a temperature of from about 50.degree.-110.degree. C., to provide an intermediate compound of the formula ##STR24## (b) isolating the intermediate compound and heating said intermediate in the presence of reaction inert organic solvent at a temperature of from about 120.degree.-200.degree. C.
Dependencies are inferred from the claim text.