AbstractTreatment of 3‐aminobenzo‐as‐triazines with bromoacetaldehyde ethylene acetal give linear tricyclic imidazobenzo‐as‐triazines, where 3‐amino‐7‐methylbenzo‐as‐triazine 1‐oxide yields the angular isomer. The structures of these compounds have been established by comparing their nmr spectra to those of pyrazolo [5,1‐c]‐ ands‐triazolo[5,1‐c]benzo‐as‐triazines obtained form the appropriate azo derivati