A facile base-mediated isocyanide-based three-component cycloaddition protocol for chemoselective formation of functionalized spiro-substituted furans and pyrroles derivatives has been developed. Fairly good yields of the products, the ready availability of the starting materials and the excellent chemoselectivity are the main advantages of this method.

A facile method has been developed for the preparation of densely functionalized tricyclic fused pyrimidine derivatives by three-component [3+2+1] cyclization. Fairly good yields of the products (up to 88%), the ready availability of the low-cost starting materials, the catalyst-free and mild conditions are the main advantages of this method.A facile three-component [3+2+1] cyclization protocol for the preparation of densely functionalized tricyclic fused pyrimidine derivatives has been designed.