Claims for Patent: 4,795,751

Summary for Patent: 4,795,751

Title:	5-substituted-6,8-difluoroquinolines useful as antibacterial agents
Abstract:	The present invention relates to a quinoline derivative of the formula ##STR1## wherein Z is an amino group or a halogen atom, R.sub.1 is a hydrogen atom or a methyl or ethyl group, R.sub.2 is a hydrogen atom or a methyl or fluoromethyl group, R.sub.3 and R.sub.4 are the same or different and each represents a hydrogen atom or a methyl group, and n is 1 or 2; and esters thereof and salts thereof and processes for preparation thereof. These compounds show excellent antibacterial activity and are useful antibacterial agents.
Inventor(s):	Matsumoto; Jun-ichi (Ikoma, JP), Miyamoto; Teruyuki (Sakai, JP), Egawa; Hiroshi (Toyonaka, JP), Nakamura; Shinichi (Takatsuki, JP)
Assignee:	Dainippon Pharmaceutical Co., Ltd. (Osaka, JP)
Application Number:	06/928,297
Patent Claims:	1. A member selected from the group consisting of (1) a compound of the formula ##STR55## wherein R.sub.1 is a hydrogen atom or a methyl group, R.sub.2 is a methyl or fluoromethyl group, and R.sub.3 is a hydrogen atom or a methyl group, (2) a pharmaceutically acceptable ester thereof, and (3) a pharmaceutically acceptable salt of said compound (1) or said ester (2). 2. 5- Amino-1-cyclopropyl-6,8-difluoro-7-(3-methyl-1-piperazinyl)-1,4-dihydro-4-o xoquinoline-3-carboxylic acid or a pharmaceutically acceptable acid addition salt thereof. 3. 5-Amino-1-cyclopropy l-6,8-difluoro-7-(3,5-dimethyl-1-piperazinyl)-1,4-dihydro-4-oxoquinoline-3- carboxylic acid or a pharmaceutically acceptable acid addition salt thereof. 4. An antibacterial composition which comprises an antibacterially effective amount of a compound, ester or salt there of as defined in claim 1 and a pharmaceutically acceptable carrier therefor. 5. A method for the treatment of a bacterial infectious disease which comprises administering an antibacterially effective amount of a compound, ester or salt thereof as defined in claim 1 to a warm-blooded animal. 6. A member selected from the group consisting of (1) a compound of the formula ##STR56## wherein R.sub.1 is a hydrogen atom or a methyl group, R.sub.2 is a hydrogen atom or a methyl or fluoromethyl group, and R.sub.3 is a hydrogen atom or a methyl group, (2) a pharmaceutically acceptale ester thereof, and (3) a pharmaceutically acceptable salt of said compound (1) or said ester (2). 7. 1- Cyclopropyl-5,6,8-trifluoro-7-(1-piperazinyl)-1,4-dihydro-4-oxoquinoline-3- carboxylic acid or a pharmaceutically acceptable acid addition salt thereof. 8. 1-Cyclopropyl-5,6,8-trifluoro-7-(4-methyl-1-piperazinyl)-1,4-dihydro-4-o xoquinoline-3-carboxylic acid or a pharmaceutically acceptable acid addition salt thereof. 9. 1-Cyclopropyl-5,6,8- trifluoro-7-(3-methyl-1-piperazinyl)-1,4-dihydro-4-oxoquinoline-3-carboxyli c acid or a pharmaceutically acceptable acid addition salt thereof. 10. An antibacterial composition which comprises an antibacterially effective amount of a compound, ester or salt thereof as defined in claim 6 and a pharmaceutically acceptable carrier therefor. 11. A method for the treatment of a bacterial infectious disease which comprises administering an antibacterially effective amount of a compound, ester or salt thereof as defined in claim 6 to a warm-blooded animal.