TEMPO-maleimide, 4-Maleimido-TEMPO, MAL 6, 4-(2,5-Dihydro-2,5-dioxo-1H-pyrrol-1-yl)-2,2,6,6-tetramethyl-1-piperidinyloxy

N-(1-Oxyl-2,2,6,6-tetramethyl-4-piperidinyl)maleimide (TTFA) is a reactive molecule that belongs to the class of maleimides. TTFA has been shown to be stable in physiological levels and is not toxic at low concentrations. TTFA binds to serine protease enzymes and inhibits their activity. This inhibition can be used as a model for the inhibition of influenza virus replication by serine proteases. TTFA inhibits translation in a variety of model systems, including yeast, bacteria and mammalian cells. TTFA also inhibits mitochondrial protein synthesis in a model system with rat liver mitochondria and human leukemia cells. In addition, TTFA inhibits fatty acid biosynthesis in yeast cells. The reactivity of this molecule makes it useful for studying the dynamics of protein folding under physiological conditions.