Pharmacological management remains the primary method to treat epilepsy and neuropathic pain. We have advanced a novel class of anticonvulsants termed functionalized amino acids (FAAs). In this study, we examine FAA derivatives from which the terminal acetyl moiety was removed and termed these compounds primary amino acid derivatives (PAADs). Twenty-seven PAADs were prepared; the central C(2) R-substituent was varied, including C(2) stereochemistry, and the compounds were tested in rodent models of seizures and neuropathic pain. C(2)-Hydrocarbon N-benzylamide PAADs were potent anticonvulsants and excellent anticonvulsant activity (mice, ip; rat, po) was observed for C(2) R-substituted PAADs in which the R group was ethyl, isopropyl, or tert-butyl, and the C(2) stereochemistry conformed to the d-amino acid configuration ((R)-stereoisomer). These values surpassed the activities of several clinical antiepileptic drugs. The C(2) (R)-ethyl and C(2) (R)-isopropyl PAADs also displayed excellent activities in the mouse (ip) formalin neuropathic pain model. Significantly, unlike the FAA structure-activity relationship, PAAD anticonvulsant activity increased upon substitution of a methylene unit for a heteroatom in the R-substituent that was one atom removed from the C(2) site, suggesting that these PAADs function by a different pathway than FAAs.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.