2,6-Lutidine → {3-[3-(2-{Benzyl-[(R)-2-(8-benzyloxy-2-oxo-1,2-dihydroquinolin-5-yl)-2-(tert-butyldimethylsilanyloxy)ethyl]amino}ethyl)phenylcarbamoyl]-propyl}methylcarbamic Acid tert-Butyl Ester

Participants

Reaction Steps

To a stirred solution of 4-(tert-butoxycarbonylmethylamino)butyric acid (72.0 mg, 0.331 mmol); 5-[(R)-2-{[2-(3-aminophenyl)ethyl]benzylamino}-1-(tert-butyl-dimethylsilanyloxy)ethyl]-8-benzyloxy-1H-quinolin-2-one (210 mg, 0.331 mmol); 2,6-lutidine (46.5 μL, 0.398 mmol); and N-(3-dimethylaminopropyl)-N-ethylcarbodiimide hydrochloride (69.8 mg, 0.364 mmol) in DMF (3 mL) at room temperature was added a solution of 1-hydroxy-7-azabenzotriazole in DMF (0.5 M, 0.729 mL, 0.364 mmol). The resulting mixture was stirred at room temperature overnight. LC-MS (Method 2-90) showed product was present (Rt 4.56 min; m/z 833.6 [M+H]+). Water was added and this mixture was diluted with aqueous 10% lithium chloride solution and DCM. The layers were separated and the organic layer was washed with aqueous 10% lithium chloride solution (2×), dried over sodium sulfate, filtered and concentrated under reduced pressure. The residue was further concentrated under high vacuum to give the title compound (containing a minor amount of DMF), which was used in the next reaction without further purification.

Provenance & Evidence