2-[4-(1-Methyl-piperidin-4-yl)-butoxy]-isonicotinonitrile. To a solution of 4-(1-methyl-piperidin-4-yl)-butan-1-ol (1.0 g, 5.85 mmol, 1.0 equiv) in DMF (25 mL) at 0° C. was added sodium hydride (60% dispersion in oil, 0.28 g, 7.02 mmol, 1.2 equiv). The mixture was warmed to rt and stirred for 1 h. The mixture was then re-cooled to 0° C. and a solution of 2-chloro-isonicotinonitrile (0.81 g, 5.85 mmol, 1.0 equiv) in DMF (10 mL) was added dropwise. The mixture was stirred at rt for 18 h, then was diluted with water (25 mL) and satd. aq. NaHCO3 (100 mL). The mixture was extracted with chloroform (3×100 mL), and the combined extracts were concentrated. Purification by Method 2 afforded 0.44 g (28%) of title compound. MS (electrospray): mass calculated for C16H23N3O, 273.18; m/z found, 274.4 [M+H]+. 1H NMR (400 MHz, CD3OD): 8.28 (dd, J=5.2, 0.7 Hz, 1H), 7.05 (dd, J=5.2, 1.3 Hz, 1H), 6.99-6.95 (m, 1H), 4.21 (t, J=6.6 Hz, 2H), 2.88-2.79 (m, 2H), 2.26 (s, 3H), 1.95-1.83 (m, 2H), 1.81-1.59 (m, 4H), 1.51-1.38 (m, 2H), 1.34-1.16 (m, 5H). B. 4,6-Dimethyl-2-{2-[4-(1-methyl-piperidin-4-yl)-butoxy]-pyridin-4-yl}-1H-benzoimidazole. To a stirred solution of 2-[4-(1-methyl-piperidin-4-yl)-butoxy]-isonicotinonitrile (440 mg, 1.61 mmol, 1.0 equiv) in toluene (5.0 mL) at 0° C. was added 1.0 M diisobutylaluminum hydride in toluene (2.41 mL, 2.41 mmol, 1.5 equiv). After 3 h, methanol (8 mL) and 1.0 M H2SO4 (5 mL) were added. The mixture was stirred for 30 min, and then 1.0 M NaOH (10 mL) was added, followed by satd. aq. sodium potassium tartrate (40 mL) and dichloromethane (100 mL). After stirring for 30 min, the mixture was extracted with chloroform (3×50 mL) and the combined extracts were washed with brine, dried (Na2SO4), filtered, and concentrated. The residue was partially purified by Method 2 to afford 318 mg of a mixture of 2-(4-piperidin-4-yl-butoxy)-pyridine-4-carbaldehyde and several other unidentified products. A portion of the crude of 2-(4-piperidin-4-yl-butoxy)-pyridine-4-carbaldehyde (100 mg), 3,5-dimethyl-benzene-1,2-diamine (70 mg), and Na2S2O5 (93 mg) were stirred in DMF (3 mL) at 90° C. for 18 h. The reaction mixture was loaded directly on silica gel and purified according to Method 2, which afforded 38 mg of the title compound. MS (electrospray): mass calculated for C24H32N4O, 392.26; m/z found 393.4 [M+H]+. 1H NMR (400 MHz, CD3OD): 8.25 (d, J=5.3 Hz, 1H), 7.62 (dd, J=4.5, 1.0 Hz, 1H), 7.48 (s, 1H), 7.24 (s, 1H), 6.95 (s, 1H), 4.34 (t, J=6.6 Hz, 2H), 2.91-2.83 (m, 2H), 2.58 (s, 3H), 2.43 (s, 3H), 2.25 (s, 3H), 2.07-1.95 (m, 2H), 1.86-1.69 (m, 5H), 1.57-1.18 (m, 6H). The following compounds in Examples 146-151 were prepared according to the methods described for Example 145.
