Triethylamine → 3-(4-Benzyloxy-phenyl)-2(S)-[(4-oxo-4H-chromene-3-carbonyl)-amino]-propionic acid methyl ester

Participants

Reaction Steps

To a stirring solution of 360 mg (2 mmol) of chromone-3-carboxylic acid in 25 mL of CH2Cl2 at 0° C. were added several drops of DMF followed by 1 mL of 2M solution of oxalyl chloride in CH2Cl2. The resulting solution was stirred 3 h at rt and 643 mg (2 mmol) of O-benzyl-L-tyrosine methyl ester hydrochloride and 0.2 g (2.0 mmol) of triethylamine in 15 mL of CH2Cl2 were added and stirring continued overnight. Solvent was removed under reduced pressure. Product was purified by LCC on SiO2 (Hexane: EtOAc 13:7) providing 83 mg of title compound as a white solid: low resolution MS (ES+ (M+H), 458; RP-HPLC (Dynamax C-8 25 cm×4.1 mm; 50-90% CH3CN in H2O with 0.1% TFA buffer; 15 minutes; 2 mL/min): tr=10.44 min.

Provenance & Evidence