A potent, orally bioavailable inhibitor of PORCN (IC50s = 18.1 and 70 nM for mouse and Xenopus PORCN, respectively); inhibits β-catenin reporter activity (IC50 = 2.9 nM) and reduces the interaction of Wnt with its carrier protein WLS via decreased Wnt palmitoleation in STF3A cells; inhibits PA-1 teratocarcinoma colony formation in soft agar (IC50 = 35 nM); reduces tumor growth in a dose-dependent manner in mice carrying a mouse mammary tumor virus LTR-Wnt1 transgene and in A-1 and NCCIT teratocarcinoma mouse xenograft models (1-10 mg/kg); reduces growth and induces differentiation in colon adenocarcinoma mouse xenograft models that contain RSPO translocations,