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Preparation of 4-Methoxy-7-(3-hydroxy-1-butyn-1-yl)-6-azaindole: To a mixture of 4-methoxy-7-bromo-6-azaindole (0.200 g, 0.88 mmol), PdCl2(PhCN)2 (0.017 g, 0.044 mmol), tri-2-furylphosphine (0.0410 g, 0.176 mmol) and CuI (0.017 g, 0.088 mmol) was added piperidine (10 mL), followed by 3-butyn-2-ol (0.09 mL, 1.15 mmol). The mixture was heated at 80 C. for 6 h and then the solvent was removed in vacuo. The residue was partitioned with EtOAc-H2O and then the aqueous phase was separated and re-extracted with EtOAc (*2). The combined organic layers were washed (H2O, brine), dried (Na2SO4) and concentrated to afford the title compound (0.200 g, 95%) as a brown solid which was of sufficient purity for use in the following step: 1H-NMR (MeOD): δ 7.60 (s, 1H), 7.35 (d, J=3.2 Hz, 1H) 6.55 (d, J=3.2 Hz, 1H), 4.72 (q, J=6.6 Hz, 1H), 3.94 (s, 3H), 1.48 (d, J=6.6 Hz, 3H).