A mixture of 1-[(2-hydroxy-1,2-dimethylpropyl)amino]-7-iodo-5H-pyrido[4,3-b]indole-4-carboxamide (prepared according to Examples 11 and 35, 50 mg, 0.11 mmol), 3-ethynylpyridine (18 mg, 0.17 mmol), cesium carbonate (74 mg, 0.23 mmol), and dichlorobis(tricyclohexylphosphine)palladium(II) (8.4 mg, 0.011 mmol) in DMSO (1.1 mL) was purged with nitrogen for 5 min, heated to 120° C. for 12 h, cooled to room temperature, diluted with EtOAc, and washed with water and brine. The organic layer was dried, concentrated, and purified by flash chromatography to afford the title compound. LRMS (APCI) calc'd for (C24H23N5O2) [M+H]+, 414.2. found 414.1.
