The preparation of 1,2,4‐triazolo[1,5‐c]quinazolines 4a‐d, 5, 8a‐d by cyclocondensation of 1a‐c with carboxylic acids and carboxylic anhydrides, respectively, is described. By different pathways, the 5‐thioxo‐5,6‐dihydro‐1,2,4‐triazolo[1,5‐c]quinazolines 4a‐d react with hydrazine hydrate or amines with the formation of 5‐substituted 1,2,4‐triazolo[1,5‐c]quinazolines 9 and 10a‐d. Cyclocondensation of 9 with carboxylic acids, carboxylic anhydrides, and nitrous acid, respectively, leads to the new anellated heterocycles bis‐1,2,4‐triazolo[4,3‐a:1,5‐c]quinazoline 13 and tetrazolo [1,5‐a]‐1,2,4‐triazolo[1,5‐c]quinazoline (14).

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