反应详情

To a solution of N-hydroxy-2-(4-isopropylpiperazin-1-yl)benzothiazole-6-carboxamidine (650 mg, 2.04 mmol) in acetic acid (40 mL) was added benzoylchloride (3 mL). The reaction mixture was stirred overnight at room temperature and then refluxed for 2 h. The reaction mixture was concentrated in vacuo and the residue was dissolved into 0.5 N hydrochloric acid (30 mL). The aqueous solution was extracted with diethyl ether (3×15 mL). The organic layer was discarded and the aqueous phase was basified to pH 13 with 4 N sodium hydroxide and then extracted with ethyl acetate (4×10 mL). The combined organic extracts were evaporated and the residue was recrystallized three times from a mixture of CH2Cl2 and MeOH to give 189 mg (26%) of 2-(4-isopropylpiperazin-1-yl)-6-(5-phenyl-[1,2,4]oxadiazol-3-yl)benzothiazole.

1. temperaturerefluxed for 2 h
2. concentrationThe reaction mixture was concentrated in vacuo
3. dissolutionthe residue was dissolved into 0.5 N hydrochloric acid (30 mL)
4. extractionThe aqueous solution was extracted with diethyl ether (3×15 mL)
5. extractionextracted with ethyl acetate (4×10 mL)
6. customThe combined organic extracts were evaporated
7. customthe residue was recrystallized three times
8. additionfrom a mixture of CH2Cl2 and MeOH