Cyclopentanecarboxylic acid → N-[(1R,2S)-1-[1-(4-fluorophenyl)indazol-5-yl]oxy-1-(3-methoxyphenyl)propan-2-yl]cyclopentanecarboxamide

To a stirred solution of 1,1-carbonyldiimidazole (12 mg, 70 μmol) in dichloromethane (1 ml) was added cyclopentanecarboxylic acid (11 μl, 100 μmol) to give a colorless solution. The reaction mixture was stirred for 1 h at r.t. Then a solution of (1R,2S)-1-{[1-(4-fluorophenyl)-1H-indazol-5-yl]oxy}-1-(3-methoxyphenyl)propan-2-amine (6a, 19 mg, 50 μmol) in dichloromethane (0.5 ml) was added, and the stirring was continued at r.t. overnight. The solvent was removed in vacuo, the residue dissolved in acetonitrile/water mixture, and the crude product purified by preparative HPLC. Yield 18 mg (76%).