A solution of N-(2-hydroxy-3-nitrophenyl)-3-cyclopentyloxy-4-methoxy-phenylacetamide (2.0 g) and pyridinium p-toluene-sulphonate (500 mg) in xylene (140 ml) was heated at reflux, under nitrogen, overnight. The reaction mixture was cooled to room temperature, diluted with water (100 ml) and extracted with dichloro-methane (3×75 ml). The combined organic extracts were washed with water (3×100 ml), brine (100 ml), dried (CaSO4) and evaporated in-vacuo to yield an orange oil. The oil was purified by flash chromatography (SiO2; dichloromethane; ethanol; ammonia (50:1:0.1)) to yield the title compound (1.107 g, 58%) as an orange solid (mp 95-98.5° C.).
