1-Ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl)-1,8 naphtyridine-3-carboxylic acid. Sesquihydrate, processes for the preparation thereof and use thereof as antibacterial agents.

摘要

Novel 1-ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl)-1,8-naphthyridine-3-carboxylic acid sesquihydrate (ATT-2266 sesquihydrate).

The aforesaid compound can be prepared by heating 1-ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl)-1,8-naphthydrine-3-carboxylic acid at a temperature above about 60°C in the presence of water in an amount enough to form the sesquihydrate.

This sesquihydrate is much more stable than the anhydrate and the trihydrate and is superior to the anhydrate in the rate of dissolution and transference into the body through the intestines. The antibacterial activities in vitro and in vivo of the sesquihydrate are essentially same with those of known AT-2266. Thus, it is especially useful as a pharmaceutical compound.