To carbonic acid tert-butyl ester 2,4-difluoro-3-formyl-phenyl ester (39, 0.405 g, 15.7 mmol) in methanol (36 mL), under an atmosphere of nitrogen, was added 5-pyridin-3-yl-1H-pyrrolo[2,3-b]pyridine (89, 288.0 mg, 14.8 mmol, prepared as described in Example 17) and potassium hydroxide (145.0 mg, 25.9 mmol). The reaction was stirred at room temperature overnight. Then, the reaction was poured into water, and extracted with ethyl acetate. The organic layer was washed with brine, dried over anhydrous sodium sulfate and concentrated. The mixture was purified by silica gel column chromatography eluting with 4% methanol in methylene chloride to provide two separate compounds, a colorless oil (P-0009, 0.23 g, 44.1%, MS (ESI) [M+H+]+=354.1), and a colorless oil (P-0042, 0.050 g, 9.2%, MS (ESI) [M+H+]+=367.1).
