N-((6-(5-Methoxy-1-methyl-1H-indol-3-yl)-5-((2-(trimethylsilyl)ethoxy)methyl)-5H-pyrrolo[2,3-b]pyrazin-2-yl)methyl)benzamide (0.118 g, 0.218 mmol) in 1,4-dioxane (3 mL) was treated with Lawesson's Reagent (0.070 g, 0.17 mmol) and was heated to about 80° C. in an oil bath for about 20 min. The mixture was cooled to ambient temperature and then mercuric acetate (0.073 g, 0.23 mmol) was added. The mixture was stirred for about 60 min at ambient temperature then another portion of mercuric acetate (0.069 g, 0.22 mmol) was added and stirring was continued for about 20 min at ambient temperature. The mixture was diluted with EtOAc (20 mL) and then filtered. The filtrate was concentrated under reduced pressure and the material was purified by silica gel chromatography eluting with EtOAc to give 7-(5-methoxy-1-methyl-1H-indol-3-yl)-6-((2-(trimethylsilyl)ethoxy)methyl)-6H-imidazo[1,5-a]pyrrolo[2,3-e]pyrazine (0.055 g, 48%): LC/MS (Table 2, Method d) Rt=1.91 min; MS m/z: 524 (M+H)+.
