This invention relates to compounds having the Formula I: or a pharmaceutically acceptable salt, prodrug or solvate thereof, wherein Het and R<;SUB>;5<;/SUB>;-R<;SUB>;8 <;/SUB>;are set in the specification. The invention also is directed to the use of compounds of Formula I for the treatment of neuronal damage following global and focal ischemia, for the treatment or prevention of neurodegenerative conditions such as amyotrophic lateral sclerosis (ALS), and for the treatment, prevention or amelioration of both acute or chronic pain, as antitinnitus agents, as anticonvulsants, and as antimanic depressants, as local anesthetics, as antiarrhythmics and for the treatment or prevention of diabetic neuropathy.