Pyridine → 2(R)-(3-chloro-4-methanesulfonyl-phenyl)-3-cyclopentyl-N-[5-(2-methylpropenyl)-pyrazin-2-yl]-propionamide

Participants

Reaction Conditions

Reaction Steps

A solution of 2(R)-(3-chloro-4-methanesulfonyl-phenyl)-3-cyclopentyl-propionic acid (prepared as in Example 1, 930 mg, 2.82 mmol) in methylene chloride (10 mL) was treated with oxalyl chloride (490 μL, 5.64 mmol) and N,N-dimethylformamide (1 drop). The mixture was stirred at 25° C. for 2 h. The reaction mixture was concentrated in vacuo, and the residue was dried in vacuo. The residue was then dissolved in benzene, and the solvents were concentrated in vacuo. The residue was dried in vacuo. This material was dissolved in methylene chloride (10 mL), cooled to 0° C., and then treated with a mixture of 2-amino-5-(2,2-dimethylvinyl)-pyrazine (420 mg, 2.82 mmol) and pyridine (340 μL) in methylene chloride (10 mL). The ice bath was removed, and the solution was stirred at 25° C. overnight. The mixture was extracted with methylene chloride and a 0.1N aqueous hydrochloric acid solution. The organic layer was washed with a saturated aqueous sodium chloride solution, dried over sodium sulfate, filtered, and concentrated in vacuo. Flash chromatography (Merck Silica gel 60, 230–400 mesh, 2/1 hexanes/ethyl acetate) afforded the 2(R)-(3-chloro-4-methanesulfonyl-phenyl)-3-cyclopentyl-N-[5-(2-methylpropenyl)-pyrazin-2-yl]-propionamide (1.10 g, 85%) as a light yellow foam.

Provenance & Evidence