To a solution of 2-docosa-4,7,10,13,16,19-hexaenamido-4-methylpentanoic acid (50 mg, 0.11 mmol) and ethyl 2-hydroxybenzoate (19 mg, 0.11 mmol) in CH3CN/THF (1:1, 0.5 mL) at −10° C. was added DCC (12 mg, 0.11 mmol) and DMAP (1 mg). The mixture was stirred (RT, 16 h), filtered and concentrated under reduced pressure. The crude product was purified by silica gel chromatography (EtOAc-PE, 0-20%) to afford ethyl 2-(2-docosa-4,7,10,13,16,19-hexaenamido-4-methylpentanoyloxy)benzoate (40 mg, 67%) as colorless oil. Mass calculated for C37H51NO5=589.80; found: [M+H]+=590.4.
