The mammalian target of rapamycin (mTOR) is a central regulator of cell growth, metabolism, and angiogenesis and an emerging target in cancer research. High throughput screening (HTS) of our compound collection led to the identification of 3-(4-morpholin-4-yl-1- piperidin-4-yl-1 H-pyrazolo [3, 4-d] pyrimidin-6-yl) phenol (5a), a modestly potent and nonselective inhibitor of mTOR and phosphoinositide 3-kinase (PI3K). Optimization of ...