N1-((ethylimino)methylene)-N3,N3-dimethylpropane-1,3-diamine hydrochloride (235 mg, 1.228 mmol), 1H-benzo[d][1,2,3]triazol-1-ol (166 mg, 1.228 mmol), and 1-(1-(4-chlorobenzyl)-1H-indole-2-carbonyl)piperidine-4-carboxylic acid (390 mg, 0.982 mmol) were dissolved in 4.0 mL of DCM. The reaction was stirred for ten minutes before adding N-ethyl-N-isopropylpropan-2-amine (0.214 ml, 1.228 mmol) and 2-(pyridin-2-yl)ethanamine (100 mg, 0.819 mmol) as a 1.0 mL DCM solution. The reaction was stirred overnight at room temperature. It was diluted with water and ethyl acetate. The organic phase was washed with water, saturated sodium bicarbonate (twice), and saturated sodium chloride. The organic phase was dried over magnesium sulfate, filtered and concentrated. The crude material was triturated with ether and ethyl acetate and filtered to obtain white solid as a product. 1H-NMR (400 MHz, DMSO-d6) 8.46, 7.84, 7.66, 7.60, 7.51, 7.37-7.27, 7.24-7.14, 7.12-7.03, 6.69, 5.46, 4.58-3.75, 3.37, 3.12-2.67, 2.34-2.25, 1.59, 1.33
