The compound prepared in Example 72 (0.13 g) was suspended in a mixture of tetrahydrofuran (6 mL), methanol (6 mL), water (1.5 mL) and concentrated hydrochloric acid (1.5 mL) and heated at reflux overnight. The reaction mixture was cooled to room temperature and poured into a saturated aqueous sodium bicarbonate solution and extracted into ethyl acetate. The organics were dried over anhydrous magnesium sulfate and concentrated. The residue was purified by column chromatography on silica gel to obtain the title compound (0.040 g) having the following physical data.
