cycloadduct and rearranged NH,NH- dihydro cycloadduct were isolated. They were transformed, dependent on the reaction conditions into 1,2-di- azepine derivative, 4-isopropyl substituted pyridazine derivative, diazabicyclo/4.l.0/heptenone derivative and pyrazolo/3,4-d/pyridazine derivative. 1,5- Sigmatropic rearrangements were observed, when was heated in PPA or concentrated sulphuric acid to give pyrazolo/3