1-Azakenpaullone is a selective inhibitor of glycogen synthase kinase-3β

Kenpaullone derivatives with a modified parent ring system were synthesized in order to develop kinase inhibitors with enhanced selectivity. Among the novel structures, 1-azakenpaullone was found to act as a selective GSK-3β versus CDK1 inhibitor. The charge distribution within the 1-azakenpaullone molecule is discussed as a possible explanation for the enhanced GSK-3β selectivity of 1-azakenpaullone compared to other paullone derivatives.