Design, synthesis and fungicidal evaluation of novel psoralen derivatives containing sulfonohydrazide or acylthiourea moiety

To search a novel lead structure for antiphytopathogenic fungus agent, a series of novel psoralen derivatives possessing sulfonohydrazide or acylthiourea structure were designed and synthesized, and their fungicidal activity against seven phytopathogens was evaluated. Their structures were confirmed by melting points, (1)H NMR, (13)C NMR and HRMS, and the typical crystal structure was determined by X-ray diffraction for validation. Preliminary fungicidal activity showed that some of the title compounds exhibited certain-to-high fungicidal activity. Compound I-13 exhibited good fungicidal activity against Botrytis cinerea, Cercospora arachidicola and Physalospora piricola with EC(50) values of 12.49, 13.22 and 12.12 μg/mL, respectively. Compounds II-9 and II-15 showed over 90% inhibition against B. cinerea at 50 μg/mL in vitro. In particular, II-9 exhibited significant higher fungicidal activity with a lower EC(50) value of 9.09 μg/mL than the positive control YZK-C22 (13.41 μg/mL). Our studies found that sulfonohydrazide or acylthiourea-containing psoralen derivatives were promising fungicide leads deserve for further study. GRAPHICAL ABSTRACT: [Image: see text] SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s11030-022-10402-y.