5-Iodowillardiine
5-Iodowillardiine is a selective agonist for some kainate receptor subunits with only limited effects at AMPA receptors. It activates kainate receptors containing GluK1 or GluK5 subunits, but it does not act on GluK2 subunits. It is an excitotoxic neurotoxin in vivo, but has proved highly useful for characterising the subtypes and function of the various kainate receptors in the brain and spinal cord.