Potato virus Y (PVY) is a highly
destructive pathogen that infects Solanum tuberosumvL., commonly known as potato, a crop that
produces one of the most crucial food staples of the world. The PVY
viral infection can considerably reduce the yield and quality of potatoes,
thereby causing significant economic ramifications. Given the unsatisfactory
performance of commercially available antiviral agents against PVY,
we synthesized a series of novel indole-derived compounds followed
by their bioevaluation and investigation of the mechanisms governing
their anti-PVY activity. These indole-based derivatives contain dithioacetal
as a key chemical moiety, and most of them exhibit promising anti-PVY
activities. In particular, compound B2 displays remarkable in vivo protective and inactivating properties, with half-maximal
effective concentration (EC50) values of 209.3 and 113.0
μg/mL, respectively, in stark contrast to commercial agents
such as ningnanmycin (EC50 = 281.4 and 136.3 μg/mL,
respectively) and ribavirin (EC50 = 744.8 and 655.4 μg/mL,
respectively). The mechanism using which B2 enhances
plant immune response to protect plants from PVY is elucidated using
enzyme activity tests, real-time quantitative polymerase chain reaction
(RT-qPCR), and proteomics techniques. This study aims to pave the
way for developing candidate pesticides and related molecules using
antiphytoviral activity