Design, synthesis, and antiviral activities of 1,5-benzothiazepine derivatives containing pyridine moiety.

In our previous work, a series of novel benzothiazepine derivatives containing pyridine moiety were successfully synthesized through chalcone 1,3-dipolar cycloaddition and determined their antiviral activity against tobacco mosaic virus (TMV). Bioassay results indicated that most of these target compounds exhibited improved curative, protection, and inactivation activity in vivo than the commercial agent ningnanmycin. Particularly, compound 3m exhibited marked curative activity against TMV, with an EC value of 352.2 μM, which was even better than that of ningnanmycin. The compound was identified as the most promising candidate for inhibiting plant virus and an excellent compound with antiviral activities against TMV. Structure-activity relationship experiment indicated that the 1,5-benzothiazepine moiety is crucial for potent anti-TMV activity.