BG-323

BG-323 is an experimental **small-molecule antiviral** from the 2-thioxothiazolidin-4-one chemical series that was identified through rational design as an inhibitor of the **flaviviral NS5 RNA capping enzyme**. It has been reported to inhibit the GTP-binding and guanylyltransferase functions of NS5, thereby interfering with viral RNA cap formation and suppressing replication of flaviviruses in preclinical systems. In published studies, BG-323 showed activity in a dengue virus subgenomic replicon assay and reduced replication of West Nile virus, yellow fever virus, and Powassan virus in cell culture, but murine studies reported limited in vivo efficacy, likely related in part to unfavorable pharmacokinetic and bioavailability properties. It appears to have remained a preclinical research compound rather than an approved or clinically developed medicine.

Other names

(E)-{3-[5-(4-tert-butylbenzylidene)-4-oxo-2-thioxo-1,3-thiazolidin-3-yl]propanoic acid}