To a suspension of 1-(4-fluorophenyl)-2-(2-fluoropyridin-4-yl)ethane-1,2-dione 2-oxime (Example 1, Step B) (400 mg, 1.52 mmol) in acetic acid (7.6 mL) was added benzaldehyde (170 μL, 1.68 mmol) followed by methylamine (144 μL, 40 wt. % in H2O, 1.68 mmol), and the mixture was heated for 41 hours at 100° C. It was cooled and acetic acid was removed in vacuo. The residue was taken up in H2O and was concentrated in vacuo two times. This was repeated with toluene to obtain crude residue. The crude residue was dissolved in a mixture of CH2Cl2/MeOH, filtered off solid (unreacted, hydrolyzed imidazole), and the solvent was removed in vacuo. The crude product was pre-absorbed on silica gel and purified by flash chromatography eluting with 5% MeOH/CH2Cl2 followed by 10% 2M NH3 in MeOH/CH2Cl2 to obtain 270 mg of the title compound.
