A thienopyrimidinylcarboxamide that acts as a highly potent, reversible pan sirtuin (SIRT) inhibitor (IC50 = 15, 10, and 33nM for SIRT1, 2, and 3, respectively). Shown to bind to the SIRT catalytic site and occupy both the nicotinamide C-pocket and acetyl lysine substrate channel. Exhibits high selectivity over a panel of protein kinases, nuclelar receptors, GPCRs, and ion-channels (IC50 > 10uM). Poorly affects hERG and cytochrome P450s (> 50uM). Exhibits desirable stability in microsomal preparations (human CLint = 15.8 uL/min/mg, mouse CLint = 12.7uL/min/mg) and high solubility (297uM), and low LogD (2.73).