3-oxo-1,4-benzothiazine derivatives
AssigneeSanten Pharmaceutical Co., Ltd.
InventorsYoichi Kawashima, Atsutoshi Ota, Hiroyuki Mibu
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Abstract
This invention offers the compounds of the formula [I]which are useful for treatment of cataract. ##STR1## wherein R.sup.1 is hydroxy which can be protected by a protective group; R.sup.2 is lower alkyl; R.sup.3 is hydrogen, lower alkyl, hydroxy, which can be protected by a protective group, or lower alkoxy, and the said lower alkyl can be substituted by hydroxy, which can be protected by a protective group, amino or lower alkylamino; R.sup.4 is carboxy which can be converted to ester or amide, and A is alkylene.
Claims12
A compound having the following formula (I) or a salt thereof, ##STR5## wherein R.sup.1 is hydroxy, lower alkanoyloxy, lower alkylsulfonyloxy, phenylsulfonyloxy, methylphenylsulfonyloxy, lower alkoxymethyloxy, benzoyloxy, benzyloxymethyloxy, tetrahydropyranyloxy or trimethylsilyloxy;
- R.sup.2 is lower alkyl;
- R.sup.3 is hydrogen, lower alkyl, hydroxy, lower alkanoyloxy, lower alkylsulfonyloxy, phenylsulfonyloxy, methylphenylsulfonyloxy, lower alkoxymethyloxy, benzoyloxy, benzyloxymethyloxy, tetrahydroxpyranyloxy, trimethylsilyloxy or lower alkoxy, and the said lower alkyl can be substituted by hydroxy, lower alkanoyloxy, lower alkylsulfonyloxy, phenylsulfonyloxy, methylphenylsulfonyloxy, lower alkoxymethyloxy, benzoyloxy, benzyloxymethyloxy, tetrahydropyranyloxy, trimethylsilyloxy, amino or lower alkylamino;
- R.sup.4 is carboxy, lower alkoxycarbonyl, phenyl lower alkoxycarbonyl, aminocarbonyl, lower alkylaminocarbonyl or phenyl lower alkylaminocarbonyl, and
- A is alkylene having 1 to 10 carbon atoms.
4-Carboxymethyl-2-(3,5-di-tert.-butyl-4-hydroxybenzylidene)-3,4 -dihydro-3-oxo-2H-1,4-benzothiazine.
4-(3-Carboxypropyl)-2-(3,5-di-ter t.-butyl-4-hydroxybenzylidene)-3,4-dihydro-3-oxo-2H-1,4-benzothiazine.
4-Carboxymethyl-3,4-dihydro-2-(3,5-dimethyl-4-hydroxybenzylidene)-3 -oxo-2H-1,4-benzothiazine.
2-(3-tert.-Butyl-4-hydr oxybenzylidene)-4-carboxymethyl-3,4-dihydro-3-oxo-2H-1,4-benzothiazine.
Dependencies are inferred from the claim text.