Synthesis and antifungal activity of 6-(piperazin-1-yl)-harmine amide derivatives

In order to explore the antifungal activity of 6-(piperazin-1-yl)-harmine amide derivative, based on previous derivative studies, 15 novel 6-(piperazin-1-yl)-harmine derivatives were designed and synthesized. The antifungal activity was evaluated and the structure-activity relationship was analyzed. The in vitro bioassay results demonstrated that the target compounds showed antifungal activities against Botrytis cinerea, Fusarium graminearum, Valsa pyri and Fusarium oxysporum, especially compound 5j displayed excellent activity against F. oxysporum with inhibition rate of 61.7% at 50 μg/mL, which was better than the positive control boscalid.