1-Hydroxybenzotriazole → 1-[trans-4-(N-tert-Butoxycarbonylglycylamino)-N-tert-Butoxycarbonyl-L-Prolyl]4-(4-Phenylbutanoyl)piperazine

Participants

Reaction Steps

Triethylamine (72 μL) and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (98.9 mg) were added to a solution of trans-4-(N-tert-butoxycarbonylglycylamino)-N-tert-butoxycarbonyl-L-proline (Compound D103 (B), 144.9 mg), 4-(4-phenylbutanoyl)l-piperazinecarboxylate (B, 100 mg), and 1-hydroxybenzotriazole (65 mg) in dichloromethane at room temperature. After stirring at room temperature for 20 hr, the reaction mixture was partitioned between ethyl acetate and 1 N hydrochloric acid. The organic layer was washed with saturated sodium hydrogen carbonate and brine. After drying over anhydrous sodium sulfate, the organic layer was evaporated in vacuo. The residue was purified by silica gel column chromatography (chloroform:methanol=50:1 to 20:1) to give the titled compound (220 mg) as a white powder: 1H-NMR(400 MHz, CDCl3) δ 1.46 (s, 18H), 1.99 (t, 2H), 2.33 (m, 2H), 2.69 (t, 2H), 3.39-3.85 (m, 13H), 7.18-7.31(m, 5H).

Provenance & Evidence