Cobalt-Catalyzed Cascade Synthesis of 5-Amino-1,2,4-triazolo[1,5-c]quinazoline Derivatives via Multiple C–N Bonds Construction

A cobalt-catalyzed three-component cascade reaction for the synthesis of functionalized 5-amino-1,2,4-triazolo[1,5-c]quinazoline derivatives is presented. The reaction involves ortho-cyanoaryl isocyanides, azides, and hydrazides, giving products in good to excellent yields. The protocol is highly scalable, as demonstrated by a gram-scale reaction of bioactive CGS-15943, providing a robust, efficient method for synthesizing triazoloquinazoline derivatives and offering significant potential for drug discovery and further modifications.