Charge a vial with 3′-chloro-4′-(1-cyclohexyl-2-oxo-pyrrolidin-3-ylmethyl)-biphenyl-2-carboxylic acid (example 6) (70 mg, 0.17 mmol), EDCl (65 mg, 0.34 mmol) and HOBt (23 mg, 0.17 mmol). Dissolve in DMF (0.1 M) and add triethylamine (95 μL, 0.68 mmol) and N-methyl piperazine (34 mg, 0.34 mmol). Stir at room temperature overnight. Pour into water and extract with ether. Dry over sodium sulfate, filter and concentrate. Purify over silica gel. Dissolve the residue in methylene chloride and acidify with 4N HCl in dioxane. Concentrate in vacuo which affords 57 mg (63%) of the title compound: Mass spectrum (apci) m/z=494.3 (M+H-HCl).
