There is much evidence for participation of electron transfer (ET) functionalities in the physiological action of drugs and toxins. The main ET agents are quinones, metal complexes, aromatic nitro compounds and iminium and imine species. Some are usually formed as metabolites. The last category, the least well known, is the focus of the review. First, examples of imines and iminiums in various bioactive classes are provided along with data on physiological activity, mechanism, ROS generation, lipid peroxidation, DNA damage, and electron affinic properties. Emphasis is on events at the fundamental molecular level. This review documents various iminoquinones, imine and iminium agents in the marine alkaloid category. Bioactivity is addressed in addition to other mechanisms. The conjugated members of those classes have the potential of participating in ET reactions which can generate reactive oxygen species or become involved in the central nervous system.
Keywords: Marine alkaloids, mechanism, iminoquinone, imine, iminium ion, reactive oxygen species, electron transfer, SAR, bioactivity