[H-].[Na+].[NH2:3][C:4]1[CH:9]=[CH:8][C:7]([N+:10]([O-:12])=[O:11])=[CH:6][C:5]=1[OH:13].CS(Cl)(=O)=O.Cl.[OH-].[Na+]>CN(C=O)C.O>[CH2:8]([O:13][C:5]1[CH:6]=[C:7]([N+:10]([O-:12])=[O:11])[CH:8]=[CH:9][C:4]=1[NH2:3])[CH2:9][CH2:4][CH2:5][CH2:6][CH3:7]General Procedure for the Preparation of the base compound and Compounds 9-16. NaH (95% powder, 0.265 g, 10.5 mmol, 3.5 equiv) was added to a solution of alkyl instituted 2-amino-5-nitrophenol (3.0 mmol) in anhydrous DMF (8 mL) at room temperature. After being stirred at the same temperature for 30 min, MsCl (1.031 g, 9.0 mmol, 3 equiv) was added to the mixture, and the stirring was continued overnight at room temperature. H2O was added to the mixture, and then it was neutralized with 5 N HCl until pH=1-2. The intermediate precipitated as a yellow solid. It was collected by filtration and washed with H2O, which was used to the next reaction without further purification. The intermediate was added to a 3 N NaOH aq solution and was stirred at 80-90° C. overnight. After being cooled, it was neutralized with 5 N HCl until pH=1-2. The precipitated solid was collected and washed with H2O and cold ether to provide the desired product, and then it was recrystallized from ethyl acetate/hexane.
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