2-(4-tert-Butyl-phenyl)-5-piperazin-1-yl-imidazo[1,2-a]pyridine (0.086 g, 0.258 mmol) was dissolved in DMSO (1 mL) and treated with 6-bromomethyl-quinoxaline (0.072 g, 0.323 mmol) followed by diisopropylethylamine (0.046 mL, 0.258 mmol). The mixture was stirred at room temperature overnight and diluted with ethyl acetate (10 mL). The solution was washed with water and saturated sodium chloride, dried over magnesium sulfate, filtered and concentrated under reduced pressure to yield the crude product. Purification by flash silica gel chromatography (40-50% acetone/hexanes) gave 0.0362 g (29%) of the title compound. HPLC (Method B): r.t.=9.6 min., purity 100% at 210-370 nm, 96.0% at 238 nm. HRMS: calcd for C30H32N6+H+, 477.27612; found (ESI, [M+H]+), 477.2786.
