A dual PI3K and mTOR inhibitor (EC50s = 4, 63, and 38 nM for PI3Kα, β, and γ isoforms, respectively, in a filter binding assay); binds to class I and class III PI3Ks (EC50s = 55.8 and 7.03 nM, for HsPI3Kβ and HsVps34, respectively); decreases protein levels of phosphorylated mTOR and Akt; inhibits the growth of squamous cell carcinoma cell lines, HONE-1, and a variant of HONE-1 resistant to cisplatin (IC50s = 7.4-27.8, 22.6, and 30.1 nM, respectively); inhibits tumor growth in a FaDu mouse xenograft model at doses of 2.5 and 5 mg/kg daily for three weeks