2-Bromo-N-(4-chlorobenzyl)-7-methyl-4-oxo-4,7-dihydrofuro[2,3-b]-pyridine-5-carboxamide (Example 79, 0.100 g) was suspended in a mixture of triethylamine (2.5 mL) and DMF (0.5 mL). CuI (0.006 g), Pd(PPh3)2Cl2 (0.017 g), and then 3-butyn-1-ol (0.038 mL) were added. The mixture was stirred at room temperature for 30 min and then was partitioned between CH2Cl2 (10 mL) and water (10 mL). The aqueous layer was separated and was extracted with CH2Cl2 (3×10 mL). The combined organic layers were washed with a sat. aq. ammonium chloride solution (10 mL), dried (MgSO4), filtered, and concentrated in vacuo. The resulting solid was purified by column chromatography (CH2Cl2/methanol; 99/1, 98/2) followed by recrystallization from ethyl acetate to yield 0.035 g of the title compound as a pale yellow solid. Physical characteristics. M.p. 242-243° C. (dec); 1H NMR (400 MHz, DMSO-d6) δ 10.51, 8.59, 7.41-7.32, 7.21, 5.01, 4.55, 3.92, 3.61, 2.67; MS (ESI+) m/z 385 (,M+H)+.
