A suspension of 3,5-difluoroisonicotinic acid (24 mg, 0.15 mmol), 2-chloro-4,6-dimethoxy-1,3,5-triazine (CDMT) (35 mg, 0.2 mmol) and 45 μl N-methyl morpholine in 2 ml DCM was stirred at r.t. for 1 h before addition of 5-(6-methylbenzothiazol-5-yl)-2-pyridylamine (55) (24 mg, 0.1 mmol). The resulting reaction mixture was stirred at r.t. for overnight then at 50° C. for 3 h. The reaction mixture was worked up with aq. NaHCO3/EA. Org. phase was washed with brine, concentrated, subjected to silica flash column chromatography to furnish 8.9 mg (3,5-difluoro(4-pyridyl))-N-[5-(6-methylbenzothiazol-5-yl)(2-pyridyl)]carboxamide (58) as yellow semi-solid. (yield: 23.3%, purity>90%).
