A convenient approach to [1,2,5]oxadiazolo[3′,4′:5,6]pyrazino[2,3-b]indoles and their heteroannulated analogues bearing various aryl substituents in the backbone has been developed. This synthetic protocol is based on Pd-catalyzed Buchwald–Hartwig and subsequent annulation by intramolecular oxidative cyclodehydrogenation. The photophysical properties for new polycycles have been measured.