An Efficient Four-Step Approach Toward Fused Triazino[1,6-a] Quinazolines.

Herein, we describe a simple, four-step process for the preparation of 1,2,3-triazino[1,6- a]quinazolin-13-ones. This method involves ring-opening, quinazoline-forming condensation, reduction, diazotization accompanied by rapid intramolecular cyclization in the last step afforded the desired products with structurally complex heterocyclic core in excellent to high yields.