75167-28-1

Upstream product

• 75167-21-4 4-(6-chloro-3-nitro-2-pyridinyl)-1-piperazinecarboxylic acid,ethyl ester 
• 75167-22-5 4-(6-Amino-3-nitro-pyridin-2-yl)-piperazine-1-carboxylic acid ethyl ester 
• 75167-24-7 4-(6-Acetylamino-3-amino-pyridin-2-yl)-piperazine-1-carboxylic acid ethyl ester 
• 75167-23-6 6-acetylamino-2-(4-ethoxycarbonyl-1-piperazinyl)-3-nitropyridine 
• 75167-27-0 6-acetylamino-2-(4-ethoxycarbonyl-1-piperazinyl)-3-fluoropyridine 

Downstream Products

• 74011-58-8 enoxacine 

Relevant academic research and scientific papers

Sesquihydrate of naphthyridine derivative, and process for the preparation thereof

Novel 1-ethyl-6-fluoro-1,4-dihyono-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-naphthyridine-3-carboxylic acid at a temperature above about 60° C. in the presence of water in an amount sufficient 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. Thus, it is especially useful as a pharmaceutical compound.