Ethyl 1-(3-tert-butoxycarbonylamino-4,6-difluorophenyl)-6,7-difluoro-5,8-dimethyl-4-oxo-1,4-dihydroquinoline-3-carboxylate → 1-(3-amino-4,6-difluorophenyl)-6,7-difluoro-5,8-dimethyl-4-oxo-1,4-dihydroquinoline-3-carboxylic Acid

Participants

Reaction Steps

To 1.8 g of the ethyl 1-(3-tert-butoxycarbonylamino-4,6-difluorophenyl)-6,7-difluoro-5,8-dimethyl-4-oxo-1,4-dihydroquinoline-3-carboxylate obtained in the Reference Example 15 was added 10 ml of 12N hydrochloric acid, and the mixture was stirred under heating and reflux condition for 4 hours. After allowing to cool, the solid precipitate was collected by filtration, washed with water and ethanol successively, and dried to obtain 1.2 g of the title compound.

Provenance & Evidence