1-(1-(4-chlorobenzyl)-1H-indole-2-carbonyl)piperidine-4-carboxylic acid (393 mg, 0.990 mmol), 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (237 mg, 1.23 mmol), and 1-Hydroxybenzotriazole (167 mg, 1.23 mmol) were dissolved in 2.0 mL of DCM. The reaction was allowed to stir for 10 minutes before N,N-Diisopropylethylamine (216 μL, 1.059 mmol) and m-tolylmethanamine (100 mg, 0.83 mmol) were added as a 1.0 mL DCM solution. The reaction was allowed to stir overnight. The reaction was diluted with water and ethyl acetate. The layers were separated and the organic layer was washed with another aliquot of water. The ethyl acetate layer was washed with 1N HCl followed by saturated sodium bicarbonate then saturated sodium chloride. The organic layer was dried over magnesium sulfate, filtered and concentrated. The crude material was triturated with methanol and filtered under vacuum to obtain pure product as a white solid. Yield: 190 mg (White solid)
