1-Oxo-3-phenyl-6-(3-phenyl-propoxy)-1H-indene-2-carboxylic acid ethyl ester (1.5 g, 3.64 mmol) obtained in Example 7 was dissolved in ethanol (100 mL), hydroxylamine hydrochloride (759 mg, 10.92 mmol) and pyridine (1.15 g, 15.56 mmol) were added thereto, refluxed for 1 hr, and cooled to RT. The resulting mixture washed with saturated sodium bicarbonate and extracted with ethyl acetate. The organic layer was separated, dried over anhydrous MgSO4 and concentrated under a reduced pressure. The resulting residue was purified by flash chromatography to obtain 0.91 g of the titled compound (yield: 58%).
