Synthesis of novel cationic bolaamphiphiles from vernonia oil and their aggregated structures

Abstract

The present study describes the synthesis of a novel class of vesicle-forming bolaamphiphiles with choline ester head groups. These bolaamphiphiles were derived from vernonia oil, whose main constituent is vernolic acid, a fatty acid with a unique combination of epoxy, carboxy and unsaturated double bonds. A series of bolaamphiphiles containing amido or ester groups within the hydrophobic domain were synthesized from N, N′-alkylenebis (vernolamides) and α,ω-alkylene divernolate ester in a two-stage synthesis comprising opening of the epoxy ring with chloroacetic acid, followed by quaternization with N, N-dimethylaminoethyl acetate to form choline ester head groups. The products were characterized by FT-IR, 1H and 13C NMR, and ESI-MS. Vesicles prepared from these bolaamphiphiles have the potential to serve as a targeted drug delivery systems with selective decapsulation in the presence of the enzyme acetylcholine esterase, resulting in site-specific release of the drug.