The present invention provides agents effective to treat eye diseases, pharmaceutical compositions comprising them, methods for preparing pharmaceuticals for treatment of eye diseases comprising using the agents, use of the agents in manufacture of pharmaceuticals for treatment of eye diseases and methods for treating eye diseases comprising administering the agents or the pharmaceutical compositions. The eye diseases treated by the present invention include particularly glaucoma, especially normal tension glaucoma, or retinitis pigmentosa. The present invention provides the compound of formula (I) wherein R is as defined in the description.
