Hydrochloric Acid → cis(+/-)-4-Chloro-N-[3-ethoxy-1-(5-methyl-6-oxo-5,6-dihydro-4H-pyrrolo[3,4-d][1,3]thiazol-2-yl)piperidin-4-yl]-5-ethyl-1H-imidazole-2-carboxamide

Participants

Reaction Steps

Trimethylaluminum (1.05 M solution in hexane) (0.76 mL, 0.80 mmol) was added to a solution of ethyl cis(±)-2-(4-{[(4-chloro-5-ethyl-1H-imidazol-2-yl)carbonyl]amino}-3-ethoxypiperidin-1-yl)-4-[(methylamino)methyl]-1,3-thiazole-5-carboxylate obtained in Example (256a) (80 mg, 0.16 mmol) in toluene (3 mL), and the mixture was heated under reflux for 45 minutes. A 1 N aqueous hydrochloric acid solution was added to the reaction solution, followed by stirring. Then, the mixture was extracted with ethyl acetate. The combined organic layers were dried over anhydrous magnesium sulfate and filtered, and then the filtrate was concentrated under reduced pressure. The resulting residue was purified by silica gel column chromatography (elution solvent: dichloromethane/methanol=20/1) to obtain 25 mg of the title compound as a pale yellow solid (35%).

Provenance & Evidence