New chalcone derivatives containing morpholine-thiadiazole: Design, synthesis and evaluation of against tobacco mosaic virus.

Twenty chalcone derivatives containing morpholine-thiadiazole were designed and synthesized from the natural product chalcone. The bioactivity test results indicate that some compounds exhibit good antiviral activity against tobacco mosaic virus (TMV). In particular, the EC values for the curative and protective activity of S14 against TMV were 91.8 and 130.6 μg/mL, which was better than that of the antiviral agent ningnanmycin (NNM, 237.8, 220.6 μg/mL). The results of preliminary mechanism study indicated that S14 had strong binding capacity and affinity to tobacco mosaic virus coat protein (TMV-CP). In the chlorophyll content assay, the chlorophyll content of tobacco leaves increased significantly after the action of S14, so that it can enhance the photosynthetic capacity of plants. In addition, the results of malondialdehyde (MDA) content assay also indicated that S14 could improve the disease resistance of tobacco.