Identification,SAR Studies,and X‐ray Co‐crystallographic Analysis of a Novel Furanopyrimidine Aurora Kinase A Inhibitor

Herein we reveal a simple method for the identification of novel Aurora kinase A inhibitors through substructure searching of an in‐house compound library to select compounds for testing. A hydrazone fragment conferring Aurora kinase activity and heterocyclic rings most frequently reported in kinase inhibitors were used as substructure queries to filter the in‐house compound library collection prior to testing. Five new series of Aurora kinase inhibitors were identified through this strategy, with IC₅₀ values ranging from ～300 nM to ～15 μM , by testing only 133 compounds from a database of ～125 000 compounds. Structure–activity relationship studies and X‐ray co‐crystallographic analysis of the most potent compound, a furanopyrimidine derivative with an IC₅₀ value of 309 nM toward Aurora kinase A, were carried out. The knowledge gained through these studies could help in the future design of potent Aurora kinase inhibitors.