Ethanolamine → N-(2-Hydroxyethyl)docosa-4,7,10,13,16,19-hexaenamide

Participants

Reaction Steps

(4Z,7Z,10Z,13Z,16Z,19Z)-Docosa-4,7,10,13,16,19-hexaenoic acid (DHA, 1.2 g, 3.66 mmol) was taken up in 20 mL of CH3CN along with ethanolamine (220 μL, 3.66 mmol), HATU (1.5 g, 4.0 mmol) and DIEA (950 μL, 5.49 mmol). The resulting reaction mixture was stirred at room temperature for 2 h and then diluted with EtOAc. The organic layer was washed with saturated aqueous NaHCO3, brine, dried (Na2SO4) and concentrated under reduced pressure to afford crude (4Z,7Z,10Z,13Z,16Z,19Z)—N-(2-hydroxyethyl)docosa-4,7,10,13,16,19-hexaenamide. This material was taken up in 15 mL of CH2Cl2 along with (E)-methyl 4-chloro-4-oxobut-2-enoate (3.66 mmol) and triethylamine (765 μL, 5.49 mmol). The resulting reaction mixture was stirred at room temperature for 18 h. It was then diluted with CH2Cl2 and washed with brine. The organic layer was dried (Na2SO4) and concentrated under reduced pressure. Purification by chromatography (60% EtOAc, 40% pentane) afforded 380 mg of 2-(4Z,7Z,10Z,13Z,16Z,19Z)-docosa-4,7,10,13,16,19-hexaenamidoethyl methyl fumarate (21% yield). MS (EI) calcd for C29H41NO5: 483.3. found: 484 (M+1).

Provenance & Evidence