A mixture of 4-hydroxy-1-phenyl-1H-pyrrolo[2,3-c]pyridine-5-carboxylic acid ethyl ester (223 mg, 0.789 mmol), NCS (117 mg, 0.869 mmol) and BzOOBz (10 mg, 0.039 mmol) in carbontetrachloride (4 mL) was refluxed for 30 min. Then the reaction was cooled and concentrated, the resulting mixture was purified by column to give the desired product (100 mg). The title compound, 1H NMR (200 MHz, CDCl3): δ (ppm)=11.8 (s, 1H), 8.44 (s, 1H), 7.6-7.4 (m, 5H), 7.35 (s, 1H), 4.53 (q, 2H, J=7.4 Hz), 1.49 (t, 3H, J=7.4 Hz).
