Synthesis and antiviral activity of novel myricetin derivatives containing ferulic acid amide scaffolds

A variety of myricetin derivatives bearing ferulic acid amide scaffolds were designed and synthesized. The structures of all title compounds were determined by H-1 NMR, C-13 NMR, F-19 NMR and HRMS. Preliminary bioassays suggested that some of the target compounds exhibited remarkable antiviral activities. In particular, compound 4l possessed significant protective activity against tobacco mosaic virus (TMV), with a half maximal effective concentration (EC50) value of 196.11 mu g mL(-1), which was better than that of commercial agent ningnanmycin (447.92 mu g mL(-1)). Meanwhile, microscale thermophoresis (MST) indicated that compound 4l has strong binding capability to the tobacco mosaic virus coat protein (TMV-CP) with a dissociation constant (K-d) value of 0.34 mu mol L-1, which was better than that of ningnanmycin (0.52 mu mol L-1). These results suggested that novel myricetin derivatives bearing ferulic acid amide scaffolds may be considered as an activator for antiviral agents.