BENZOHETEROCYCLIC COMPOUNDS AND THEIR PREPARING METHOD

22.5.86, 23.7.86, 19.8.86, 30.9.86, 15.10.86, 18.12.86-JP-105655, 118568, 173370, 193838, 233837, 246050, 303515) (1703KM) 4-Oxoquinoline-3-carboxylic acid cpds. of formula (I) and their salts are new. R1 is cyclopropyl opt. substd. by 1-3 substits. selected from lower alkyl and halogen; R2 is 5-9 membered opt. unsatd. heterocyclic ring which may be substd. R3 is lower alkyl which may be substd. by 1-3 substits. selected from a 5- or 6-membered satd. heterocyclic ring, lower alkylthio, amino, lower-alkylamino, lower alkanoyloxy, OH, lower alkoxy and halogen; and X is halogen. Pref. R2 is opt. substd. 1-piperidinyl, 1-pyrrolidinyl, 1-homopiperazinyl, thiomorpholino, 1,4-diazabicyclo (4.3.0) nona-4-yl, thiomorpholino-4-oxide, thiomorpholino-4,4-dioxide, 1-hexahydropyridazinyl, 2-thiazolidinyl, 1-imidazolidinyl or 3,7-diazabicyclo (4.3.0) nona-3-yl. 10 Cpds. of (I) including 7-(4-(5-methyl) 2-oxo-1,3-dioxolen -4-yl) methyl-1-piperazinyl) -1-cyclopropyl-6-fluoro- 8-methyl-1,4-dihydro-4-oxoquinoline -3-carboxylic acid are described.