Glucose transporter 1 (GLUT1) is an inducible carrier of pentoses and hexoses, including glucose. STF-31 is an inhibitor of GLUT1 (IC50 = ~1 μM) that blocks glucose uptake. It induces necrosis in cancer cells that lack the von Hippel-Lindau tumor suppressor gene, which overexpress GLUT1. Although STF-31 binds GLUT1, suggesting a direct effect, STF-31 also inhibits nicotinamide phosphoribosyltransferase, an enzyme that induces GLUT1 expression. STF-31 is also toxic to human pluripotent stem cells (hPSCs) and can be used to selectively eliminate hPSCs from mixed cultures.