for the following products
1-Ethyl-6,7,8-trifluoro-2,4-dihydro-4-oxo-3-quinolinecarboxylic acid ethyl ester | Ethyl 1-ethyl-6,7,8-trifluoro-4-oxo-1,4-dihydroquinoline-3-carboxylate and 1-Ethyl-6,7,8-trifluoro-4-oxohydroquinoline-3-carboxylic acid ethyl ester
