4-Alkylamino-2-chloroquinoline-3-carbonitriles 4a - c react with NaN3 to give the corresponding tetrazolo[1,5-a]quinoline-4-carbonitriles 5a - c which are converted into 2-amino-quinoline-3-carbonitriles 8a - c by reaction with PPh3 via an iminophosphorane and subsequent hydrolysis. On the other hand, the new 3,4-diamino-1H-pyrazolo[4,3-c]quinoline (11) was prepared by fusion of the aminoquinolines 8a - c with hydrazine hydrate. Diazotization of 11 followed by reaction with NaN3 yielded the novel tetracyclic ring system 3-azido-1H-1,2,4,5,6,6a-hexaazabenzo[a]indacene (13)