Following General Procedure G, 1-benzyl-3-(3,4-difluorobenzylcarbamoyl)-2-isopropyl-1H-indole-6-carboxylic acid (Compound 56, 35 mg, 0.080 mmol) in DMF (4 ml) was added BOP (40 mg, 0.10 mmol) and DIPEA (20 mg, 0.11 mmol), followed by 1-amino-2-methylpropan-2-ol (10 mg, 0.10 mmol). The reaction was stirred at room temperature for 12 h, diluted with EtOAc, washed with H2O, brine, dried over Na2SO4 and concentrated in vacuo. The residue was purified by chromatography on silica gel (5:95 MeOH—CH2Cl2) to yield the title compound as yellow oil.
