Identification of 2-Benzylidene-tetralone Derivatives as Highly Potent and Reversible Firefly Luciferase Inhibitors.

The extensive applications of Firefly luciferase (Fluc) in numerous biological, biomedical, and clinical investigations rendered an urgent need for efficient and biocompatible Fluc inhibitors for the construction of novel assay platforms. Herein we describe the identification of 2-benzylidene-tetralone derivatives as highly potent and reversible Firefly luciferase inhibitors by competing with d-luciferin. The most active compound 48 was found to have >7000 fold higher potency (IC 50 = 0.25 nM) than that of the well-known luciferase inhibitor resveratrol (IC 50 = 1.9 μM) biochemically with sub- to low nanomolar IC 50 values, and it can efficiently block the Fluc generated bioluminescence in vivo.