113933-52-1Relevant articles and documents
Improved method of preparation process of oxo-fluoro cyclization ester or levo-oxo-fluoro cyclization ester
-
, (2020/02/14)
The invention discloses an improved method of a preparation process of oxo-fluoro cyclization ester or levooxo-fluoro cyclization ester. Existing preparation methods of some levofloxacin intermediateshave many side reactions and are low in yield. According to the technical scheme in the invention, by means of 2,3,4,5-tetrafluorobenzoyl chloride, N,N-dimethylaminoethyl acrylate and (L-)aminopropanol as starting raw materials and toluene and N, N-dimethylformamide added with a water removal agent organic ester or anhydride as solvents, the oxygen-fluorine cyclization ester is prepared through aone-pot reaction. According to the method, organic ester or anhydride is added, so that the loss of raw materials and the generation of by-products are reduced, the reaction yield is increased, the product quality is ensured, and the yield of the (L-)oxo-fluoro cyclization ester can be increased from 75-80% to about 90%.
Antibacterial 1,8-bridged 4-quinolone-3-carboxylic acids
-
, (2008/06/13)
A process for the preparation of a 1,8-bridged 4-quinolone-3-carboxylic acid of the formula STR1 wherein the substituents are defined hereinbelow. Some of the compound are new. The old and new compounds are antibacterials and promote animal growth.