To a solution of 77 mg (0.20 mmol) {2-[(5-Hydroxy-benzo[b]thiophene-2-carbonyl)-amino]-phenyl}-carbamic acid tert-butyl ester (4) in 3 ml ethyl acetate was added 200 mg potassium carbonate and 56 mg (0.22 mmol) 2-(bromomethyl)pyridine, hydrobromide. The reaction mixture was heated at reflux for 10 h and poured into brine. The aqueous phase was extracted with ethyl acetate and the organic phase was dried over sodium sulfate, the solvent was evaporated and the residue subjected to silica gel chromatography (petrolether/ethyl acetate 3:2) to yield (2-{[5-(Pyridin-2-ylmethoxy)-benzo[b]thiophene-2-carbonyl]-amino}-phenyl)-carbamic acid tert-butyl ester (52) (80 mg, 0.168 mmol) as colorless crystals.
