反应详情

To a suspension of methyl 1,4-dihydro-6-nitro-4-oxo-2-quinolinecarboxylate (3.72 g, 15 mmol) obtained in Example 131, Step 2 in acetonitrile (50 ml) was added chlorosulfonyl isocyanate (1.30 ml, 15 mol) and the mixture was refluxed under heating for 1 hr. The reaction mixture was cooled to room temperature and methanol was added, which was followed by concentration under reduced pressure. To the residue was added 2 mol/l aqueous sodium carbonate solution to allow suspending and the insoluble matter was collected by filtration. The insoluble matter was dried under reduced pressure at 80° C. to give methyl 4-amino-6-nitro-2-quinolinecarboxylate as crude brown crystals (3.23 g). This compound was used in the next reaction without purification.

1. temperaturethe mixture was refluxed
2. temperatureunder heating for 1 hr
3. concentrationwhich was followed by concentration under reduced pressure
4. additionTo the residue was added 2 mol/l aqueous sodium carbonate solution
5. filtrationthe insoluble matter was collected by filtration
6. customThe insoluble matter was dried under reduced pressure at 80° C.