An inhibitor of acid ceramidase (IC50 = 79 nM); inhibits acid ceramidase activity, reduces levels of sphingosine and dihydroceramide, and increases levels of ceramide in SW403 adenocarcinoma cells and RAW 264.7 murine macrophages from 0.1-20 mM; reduces acid ceramidase activity in multiple organs and increases pulmonary ceramide levels in mice at 10 mg/kg