Cell-permeable inhibitor of p70 ribosomal S6 kinase (S6K1 isoform) (Ki = 20 nM; IC50 = 160 nM). Suppresses the S6K1-mediated phosphorylation of S6, Rictor and mTOR in response to IGF1; displays no effect on the activity of RSK and MSK in vivo. Exhibits no significant inhibition of S6K2 or other AGC kinases (e.g. Akt, PKA and ROCK) in vitro. Purity 98%. MW (observed): 390.41