1,1'-Carbonyldiimidazole → 4'-(2-Phenoxy-ethylsulfanylmethyl)-biphenyl-4-carboxylic acid (4-dimethylamino-butyl)-amide

4′-(2-Phenoxy-ethylsulfanylmethyl)-biphenyl-4-carboxylic acid (4-dimethylamino-butyl)-amide was prepared as described in example 1. 4′-(2-Phenoxy-ethylsulfanylmethyl)-biphenyl-4-carboxylic acid (0.8 g, 2.19 mmol, 1 eq.) in THF was treated with 1,1′-carbonyldiimidazole (0.36 g, 2.23 mmol, 1.02 eq.). The resulting acyl imidazole was then treated with 4-dimethylaminobutylamine (0.28 g, 2.41 mmol, 1.1 eq.). When complete, the reaction was worked up to leave a yellow oil (0.72 g, 71% yield) which solidified on standing. The free base was converted to the oxalate as described in example 3 to give 4′-(2-phenoxy-ethylsulfanylmethyl)-biphenyl-4-carboxylic acid (4-dimethylamino-butyl)-amide oxalate (0.61 g) as a white solid.