Tri- and tetra-substituted guanidines which exhibit a high binding affinity to phencyclidine (PCP) receptors and, more preferably, low affinity to the brain sigma receptors. These guanidine derivatives act as non-competitive inhibitors of glutamate induced responses of the NMDA receptor by acting as blockers for the ion channel of the NMDA receptor-ion channel complex. These compounds thus exert neuroprotective activity and are useful in the therapeutic treatment of neuronal loss in hypoxia, hypoglycemia, brain or spinal cord ischemia, and brain or spinal chord trauma as well as being useful for the treatment of epilepsy, Alzheimer's disease, Amyotrophic Lateral Sclerosis, Parkinson's disease, Huntington's disease, Down's Syndrome, Korsakoff's disease and other neurodegenerative disorders.
Tri- and tetra-substituted guanidines and their use as excitatory amino acid antagonists