Continuous efforts in microwave-assisted synthesis and the structure–activity relationships'(SARs) studies of novel modified 9-oxo-thiazolo [5, 4-f] quinazoline-2- carbonitriles, allowed identification of new amidine and imidate derivatives as potent and dual CDK1/GSK-3 inhibitors. Combination of lead optimization and molecular modeling studies allowed identification of a dual CDK1/GSK-3 inhibitor (compound 13d) with ...