Synthesis of (Z)-azanediylbis(ethane-2,1-diyl) dioleate TFA salt previously described. (Z)-azanediylbis(ethane-2,1-diyl) dioleate TFA salt (4.06 g, 6.41 mmol) was stirred in DCM (60 mL) with 10% K2CO3 (30 mL) at 0-5° C. After 30 min, the organic phase was separated and the aqueous phase was further extracted with DCM (30 mL). The combined organic phases were stirred with anhydrous MgSO4 for a period of 30 minutes at 0-5° C., filtered, and washed with DCM (30 mL). To the combined filtrates were added to 2-((2-(dimethylamino)ethyl)thio)acetic acid (1.26 g, 7.70 mmol), EDC HCl salt (1.84 g, 9.62 mmol), DMAP (78.3 mg, 0.64 mmol). The thin suspension was stirred overnight at room temperature; after which a period of time, the solution became clear. Next day, deionized water (60 mL) and methanol (30 mL) were added. After stirring for 10 minutes, the clear organic layer was isolated. The turbid aqueous phase is extracted with DCM. The combined organic extracts were concentrated. Crude material was filtered through a plug of silica and taken up in DCM (40 mL) and PBS (pH=11, 50 mL) was added. The mixture was stirred at room temperature for 10 min. Then, the organic phase was separated and the aqueous phase is extracted again with DCM (15 mL). The combined organic phases were stirred with anhydrous MgSO4 for a period of 30 min. The mixture was then filtered, and washed with DCM. The combined filtrates were concentrated in vacuo to yield (Z)-((2-((2-(dimethylamino)ethyl)thio)acetyl)azanediyl)bis(ethane-2,1-diyl) dioleate (3.44 g).
