To a mixture of 2-amino-N-(5-phenoxy-thiophen-2-ylmethyl)-nicotinamide described in Example A-67 (21 mg, 0.064 mmol) and N,N-dimethylformamide (1 mL) was added N-chlorosuccinimide (13 mg, 0.096 mmol), and the solution was stirred overnight at room temperature. The reaction solution was purified by reverse phase high performance liquid chromatography (acetonitrile-water mobile phase (containing 0.1% trifluoroacetic acid) was used), and trifluoroacetic acid salt of the title compound (7.4 mg, 0.016 mmol, 24%) was obtained.
