Mechanism of N-octadecyl-N′-maleoyl-l-phenylalanine self-assembled into supramolecular structures

N-Octadecyl-N′-maleoyl-l-phenylalanine (ODMA-l-Phe) was synthesized through the condensation, deprotection and acidylation reaction of BOC-l-phenylalanine, octadecylamine and maleic anhydride. ODMA-l-Phe can self-assemble in some organic solvents and turned them into thermally reversible physical supramolecular organogels. The morphology of ODMA-l-Phe aggregates was characterized by polarized optical microscopy (POM) and field emission scanning electron microscope (FE-SEM). The aggregates of ODMA-l-Phe were needle-like fibrils with diameters of approximately 100-200 nm. The mechanism of ODMA-l-Phe self-assembly in organic solvents was investigated using 1H NMR and circular dichroism (CD). The results indicated that hydrogen bonding was one of the main driving forces for the self-assembly of ODMA-l-Phe.