Long wavelength optical control of glutamate receptor ion channels using a tetra-ortho-substituted azobenzene derivative.

A tetra-ortho-chloro substituted azobenzene unit was incorporated into a photoswitchable tethered ligand for ionotropic glutamate receptors. This compound confers the modified protein with the unusual optical responses of the substituted azo scaffold permitting channel opening with yellow and red light and channel closing with blue light.