Basic red 1 is a tetracyclic compound (it has four rings) that shares many structural similarities with the dyes in the previous problem (Chem. Rev. 1993, 93, 381–433). This compound has many significant resonance structures, and the positive charge is highly delocalized. While resonance structures can be drawn in which the positive charge is spread throughout all four rings, nonetheless, one of the rings likely bears very little of the charge relative to the other rings. Identify the ring that is not participating as effectively in resonance and suggest an explanation.