A mixture of 5-(pyridazin-4-yl)pyridin-2-amine 134-1 (53 mg, 0.31 mmol), 2-(3-methyl-4-(pyridazin-4-yl)phenyl)acetic acid 134-3 (73 mg, 0.32 mmol), HATU (122 mg, 0.32 mmol) and DIEA (80 uL, 0.46 mmol) in DMF (1.0 ml) was stirred at room temperature overnight. Then it was distributed between ethyl acetate (40 ml) and 3% Na2CO3 aqueous solution (40 ml) and extracted with 0.5 N HCl solution (30 ml). The aqueous extraction was treated with Na2CO3 to adjust the pH to around 10 followed by extraction with ethyl acetate (30 ml×2). The combined organic extractions were dried over Na2SO4 and concentrated by evaporation. The residue was subjected to reverse phase HPLC to yield 2-(3-methyl-4-(pyridazin-4-yl)phenyl)-N-(5-(pyridazin-4-yl)pyridin-2-yl)acetamide 134 as off white solid. MS m/z 383.2 (M+1).
