A potent, selective and ATP-competitive mTOR inhibitor, with IC₅₀ values of 2 and 10 nM for mTORC1 and mTORC2 respectively; Torin1 displays 1000-fold selectivity for mTOR over PI3K (EC₅₀ = 1800 nM) and exhibits 100-fold binding selectivity relative to 450 other protein kinases.