The product of Example 167A (200 mg, 0.328 mmol), ammonium chloride (115 mg, 2.152 mmol), and iron powder (113 mg, 2.021 mmol) in a mixture of water (2 mL), ethanol (4 mL) and tetrahydrofuran (4 mL) was heated at 90° C. under a nitrogen atmosphere for 1 hour. The reaction was cooled to room temperature, diluted with ethyl acetate (50 mL), and washed with water (3×50 mL) and brine (50 mL). The organic was dried over anhydrous sodium sulfate, filtered, and concentrated by rotary evaporation in vacuo. Purification by silica gel chromatography eluting with 5% methanol/methylene chloride afforded the product as a gold-colored solid (114 mg, 60%).
