Naphthoxyacetic acid → (3S)-3-[N-((1-Naphthyloxy)Acetyl)Leucinyl]Amino-4-Oxobutanoic Acid tert-Butyl Ester Semicarbazone

Participants

Reaction Conditions

Reaction Steps

To a solution of (1-naphthyloxy)acetic acid (0.150 g, 0.74 mmol) and (3S)-3-(leucinyl)amino-4-oxobutanoic acid tert-butyl ester semicarbazone (0.360 g, ca 0.83 mmol) in N-methylpyrrolidone(2.0 mL)-CH2Cl2(2.0 mL) at 0° C. (ice bath) under nitrogen was added hydroxybenzotriazole hydrate (0.130 g) followed by 1-ethyl-3-(3′,3′-dimethyl-1′-aminopropyl)carbodiimide hydrochloride (0.195 g, 1.02 mmol). After stirring at 0° C. for 1 hrs and at room temperature for 5 hrs, the mixture was partitioned between EtOAc-water. The organic phase was washed with water, 5% KHSO4, saturated NaHCO3 and saturated NaCl solutions, dried over anhydrous Na2SO4 and evaporated to dryness. The crude product was purified by flash chromatography eluting with MeOH-CH2Cl2 (2:100 then 5:100) to give the title compound (0.366 g, 94%) as a colorless foam. TLC(MeOH-CH2Cl2; 5:95) Rf=0.20.

Provenance & Evidence