1-Hydroxybenzotriazole → Ethyl cis(+/-)-2-(4-{[(4-chloro-5-ethyl-1H-imidazol-2-yl)carbonyl]amino}-3-methoxypiperidin-1-yl)-4-methyl-1,3-oxazole-5-carboxylate

Participants

Reaction Steps

The same operation as in Example (106d) was performed using ethyl cis(±)-2-(4-amino-3-methoxypiperidin-1-yl)-4-methyl-1,3-oxazole-5-carboxylate obtained in Example (107b) (0.22 g, 0.78 mmol), 4-chloro-5-ethyl-1H-imidazole-2-carboxylic acid (0.16 g, 0.92 mmol), WSC hydrochloride (0.46 g, 2.4 mmol), HOBt (0.2 g, 1.2 mmol), DMA (3 mL) and dichloromethane (3 mL). The resulting residue was purified by silica gel column chromatography (elution solvent: ethyl acetate/hexane=1/2, 1/1, 2/1, 1/0, ethyl acetate/methanol=97/3, 93/7) to obtain 0.24 g of the title compound as a light yellow solid (70%).

Provenance & Evidence