L-Isoleucine-catalyzed Michael Synthesis of N-Alkylsuccinimide Derivatives and Their Antioxidant Activity Assessment

N-Substituted succinimides having different alkyl groups were prepared by the reaction of N-substituted maleimide with aldehydes. A two-component catalyst system composed of an amino acid (L-isoleucine) and a base (KOH) was used to facilitate reaction of the a-hydrogen-containing aldehyde with N-substituted maleimide. With 20 mol % catalyst/cocatalyst, good results in term of the reaction time and yield (89-99%) of products containing contiguous quaternary and tertiary stereogenic centers were obtained. The CHN elemental analyses of N-substituted succinimides indicated appreciable purity. Structural assessment of the synthesized N-substituted succinimides was carried out by H-1 and C-13 NMR spectroscopy. The products exhibited excellent antioxidant and mild antimicrobial activities.