We, herein, describe a novel, simple, efficient and one-pot multi-component procedure for the synthesis of substituted pyrimido[4,5-d]pyrimidines via reaction of N,N-dimethyl-6-amino uracil, isothiocyanate and aromatic aldehydes promoted by 7-aminonaphthalene-1,3-disulfonic acid (ANDSA)-functionalized magnetic Fe3O4@SiO2 in water as solvent and without using any other harmful organic reagents. Compared with other reactions, using these organic–inorganic hybrid heterogeneous catalysts can help us to achieve a green procedure, high catalytic activity, easy recovery with an external magnetic field, and short reaction times. Copyright © 2017 John Wiley & Sons, Ltd.
