Diisopropylethylamine (0.28 ml, 1.64 mmol), EDC (0.088 g, 0.46 mmol) and HOAT (0.063 g, 0.46 mmol) were added to a stirred solution of 4-bromo-5-ethyl-1H-pyrrole-2-carboxylic acid (Intermediate 10, 0.1 g, 0.46 mmol) in DMF (1.5 ml) at room temperature. The resultant solution was stirred for 30 mins and a solution of 2-(4-aminopiperidin-1-yl)-6-chloroisonicotinamide hydrochloride (Intermediate 70, 0.14 g, 0.55 mmol) in 3 ml of DMF was added. The reaction was stirred overnight, then concentrated under vacuum and the residue was partitioned between water and EtOAc. The aqueous layer was extracted with EtOAc (×2) and the combined organic extracts were washed with 1 N HCl, water and brine, dried over MgSO4 and concentrated under vacuum. The residue was purified by reverse phase chromatography to give the desired product as a white solid.
