An efficient and environmentally benign domino protocol has been presented for the synthesis of structurally
diverse spirooxindoles spiroannulated with pyranopyridopyrimidines, indenopyridopyrimidines, and chromenopyridopyrimidines
involving three-component reaction of aminouracils, isatins and cyclic carbonyl compounds in deep eutectic
solvent (choline chloride-oxalic acid: 1:1) which acts as efficient catalyst and environmentally benign reaction medium.
The present protocol offers several advantages such as operational simplicity with easy workup, shorter reaction times
excellent yields with superior atom economy and environmentally benign reaction conditions with the use of costeffective,
recyclable, non-toxic and bio-degradable DES as catalyst/solvent.