An aqueous sodium hydroxide solution (3 N, 1.04 ml, 3.12 mmols) was added to a methanol (10 ml) solution of methyl 4-[4-(4,5,6,7-tetramethoxyindan-2-yl)butoxy]benzoate (920 mg, 2.07 mmols), and heated under reflux for 6 hours. Water was added to the reaction mixture, which was made acidic by adding 1 N hydrochloric acid and extracted with ethyl acetate. The organic layer was washed with a saturated aqueous sodium chloride solution, and then dried. The solvent was evaporated out in vacuo, and the resulting crude product was purified by recrystallization (from hexane-ethyl acetate) to obtain the entitled compound (855 mg) as crystals.
