4-Hydroxy-2-Quinolones. 233*. Synthesis and Diuretic Activity of 9-Bromo-7-Hydroxy-5-Oxo-2,3-Dihydro-1H,5H-Pyrido[3,2,1-ij]Quinoline-6-Carboxylic Acid Anilides

The ethyl ester of 7-hydroxy-5-oxo-2,3-dihydro-1H,5H-pyrido[3,2,1-ij]quinoline-6-carboxylic acid reaction with bromine in anhydrous acetic acid producing a mixture of the 9-bromo-substituted product and 6-ethoxycarbonyl-5,7-dihydroxy-2,3-dihydro-1H-pyrido[3,2,1-ij]quinolinium tribromide in a 1:1 ratio. It has been established experimentally that the diuretic activity of 9-bromo-7-hydroxy-5-oxo-2,3-dihydro-1H,5H-pyrido[3,2,1-ij]quinoline-6-carboxanilides increases substantially in comparison with their non-brominated analogs.