The following was added to DCM: 1-(tert-butoxycarbonyl)piperidine-4-carboxylic acid (600 mg, 2.62 mmol), DIPEA (1.37 mL, 7.85 mmol), EDC (552 mg, 2.88 mL), HOBT (441 mg, 2.88 mmol), and pyridylethylamine (0.34 mL, 2.88 mL). The solution was stirred at rt for 17 h, at which time the DCM was stripped off and 10% aq. sodium carbonate was added. Material was extracted out with EtOAc (3×). The organic extractions were pooled, dried over magnesium sulfate, and concentrated in vacuo. The residue was taken up in a small amount of EtOAc and diethyl ether was added. The precipitate was collected over a filter and washed with diethyl ether to give the title compound as an off-white solid. (Yield: 634 mg, 1.9 mmol, 73%) 1H NMR (400 MHz, CDCl3) 8.49, 7.09, 5.67-5.54, 4.10, 3.52, 2.81, 2.68, 2.14, 1.81-1.66, 1.56, 1.43
