Pyridine-4-carbonyl chloride → 2-(4-Isopropylpiperazin-1-yl)-6-(5-pyridin-4-yl-[1,2,4]oxadiazol-3-yl)benzothiazole

Participants

Reaction Steps

To a solution of N-hydroxy-2-(4-isopropylpiperazin-1-yl)benzothiazole-6-carboxamidine (1.30 g, 4.07 mmol) in acetic acid (50 mL) was added isonicotinoyl chloride (1.42 g, 10.0 mmol). The reaction mixture was stirred overnight at room temperature and then heated at refluxed for 8 h. The reaction mixture was concentrated in vacuo and the residue was dissolved into 0.5 N hydrochloric acid (40 mL). The aqueous solution was extracted with diethyl ether (3×15 mL). The organic extracts were 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 from a mixture of CH2Cl2 and MeOH to give 175 mg (11%) of 2-(4-isopropylpiperazin-1-yl)-6-(5-pyridin-4-yl-[1,2,4]oxadiazol-3-yl)benzothiazole.

Provenance & Evidence