Potassium Carbonate → HCID 19955587, compound

Participants

Reaction Steps

2-Ethyl-5,7-dimethyl-3H-imidazo[4,5-b]pyridine (0.66 g; preparable as described in Mantio et al, J. Med. Chem. 34, (1991), pp 2919/2922 and in EP-A-0400914; Merck), and anhydrous potassium carbonate (1.02 g) were added to a solution of 3-(4'-bromomethylbiphenyl-2-yl)-4-isopropoxycyclobut-3-ene-1,2-dione (1.88 g; preparable as described in Example 1(c)) in dry dimethylformamide (10 ml) and the resulting mixture was stirred at ambient temperature for approximately 16 hours. More 2-ethyl-5,7-dimethyl-3H-imidazo[4,5-b]pyridine (0.33 g) was added to the dark reaction solution obtained, and stirring was continued at ambient temperature for an additional 24 hours. The resulting dark mixture was partitioned between ethyl acetate (100 ml) and water (50 ml). The organic layer was then separated, washed with water (50 ml), and dried over magnesium sulphate. The resulting solution was evaporated to leave a dark oil which was purified by flash chromatography on silica gel (eluting with 1% industrial methylated spirit in dichloromethane) followed by flash chromatography on silica gel (eluting with ethyl acetate) and flash chromatography on silica gel (eluting with 0% rising to 2% methanol in dichloromethane) to give 3-[4'-(2-ethyl-5,7-dimethyl-3H-imidazo[4,5-b]pyrid-3-ylmethyl)biphenyl -2-yl]-4-isopropoxycyclobut-3-ene-1,2-dione, an active compound of the present invention, as a yellow foam (0.176 g) which melted slowly at 60° C. or above.

Provenance & Evidence