Chloroacetyl chloride → 3-(1-cyano-1-methylethyl)-N-{3-[(2-{[(4-methylpiperazin-1-yl)acetyl]amino}-7-nitro-1,3-benzothiazol-6-yl)oxy]phenyl}benzamide

Participants

Reaction Steps

To a solution of N-{3-[(2-amino-7-nitro-1,3-benzothiazol-6-yl)oxy]phenyl}-3-(1-cyano-1-methylethyl)benzamide (150 mg, 0.32 mmol) produced in Example 37(ii) in dimethylacetamide (2 mL) was added chloroacetyl chloride (55 μL, 0.70 mmol), and the mixture was stirred at room temperature for 2 hr. The reaction mixture was diluted with ethyl acetate (25 mL), washed successively with 5% aqueous sodium hydrogen carbonate solution (25 mL) and saturated brine (25 mL), and dried over anhydrous sodium sulfate. Insoluble material was filtered off, the filtrate was concentrated under reduced pressure, the obtained residue was dissolved in tetrahydrofuran (3 mL). Triethylamine (130 μL, 0.95 mmol) and 1-methylpiperazine (105 μL, 0.95 mmol) were added to the mixture, and the mixture was stirred at 60° C. for 4 hr. The reaction mixture was cooled to room temperature, diluted with ethyl acetate (25 mL), washed successively with water (25 mL) and saturated brine (25 mL), and dried over anhydrous sodium sulfate. Insoluble material was filtered off, the filtrate was concentrated under reduced pressure, the obtained residue was purified by basic silica gel column chromatography (methanol/ethyl acetate=0/100→15/85), and the obtained solution was concentrated under reduced pressure. The residue was crystallized from ethyl acetate/diisopropyl ether to give the title compound (162 mg, 84%) as a yellow powder.

Provenance & Evidence