Following our previous results, the reaction of 1-oxy-2-phenyl-indole with 4-nitroso-pyridine-1-oxide is now reported. The formation of the indolic di-N-oxide (III), previously isolated from other experiments, and of the indolic-pyridinic-di-N-oxide (VI), together with several other compounds, is demonstrated. As in the case of (III), the E.P.R. spectrum, in benzene and in tetrahydrofuran, of the mixed di-N-oxide (VI) shows the presence of odd electrons.