Lithium aluminium hydride (72.1 mg, 1.90 mmols) was added to a diethyl ether (6.0 ml) solution of ethyl 8-(2-ethoxycarbonyl-4,5,6,7-tetramethoxyindan-2-yl)octanoate (315 mg, 0.634 mmols), with cooling with ice. The reaction mixture was warmed to room temperature, and then stirred for 1 hour. 1N hydrochloric acid was added to the reaction mixture with cooling with ice, which was then extracted with ethyl acetate. The organic layer was washed with a saturated aqueous sodium chloride solution, and then dried. The solvent was evaporated out, and the resulting crude product was purified by silica gel column chromatography (hexane:ethyl acetate=4:1 to 1:1) to obtain the entitled compound (239 mg) as an oil.
