Purity >98% by HPLC. BMS-833923 is a potent inhibitor of Smo (Smoothened) with potential antineoplastic activity. It blocks binding of BODIPY cyclopamine (IC50 = 21 nM) and inhibits Gli activation in cell lines that express wild-type Smo or activated mutant forms of Smo (IC50s = 6-35 nM). BMS-833923 inhibits Shh pathway activity and prevents tumor growth in medulloblastoma and pancreatic carcinoma xenograft models.