50 gm of [1H-Benzimidazole-2-n-propyl-4-methyl-6-(1′-methyl benzimidazole-2′-yl)] was added to 200 ml dimethyl sulfoxide and 50 gm of sodium hydroxide. To this was added 60 gm of methyl-4-(bromomethyl)biphenyl-2-carboxylate at ambient temperature. The contents were stirred for 2 hours at 25-30° C. and then heated to 40-50 and maintained for 2 hours. About 500 ml water was added to the reaction mixture and acidified with acetic acid to pH 4.2, extract4ed twice with 250 ml of dichloromethane and the combined extracts were concentrated and isolated by filtration after addition of 300 ml acetone, dried under reduced pressure at 50-60° C. to give 75.0 gm (80%) of the title compound.
