Antifungal agents. Part 4: Synthesis and antifungal activities of novel indole[1,2-c]-1,2,4-benzotriazine derivatives against phytopathogenic fungi in vitro

• Published in: European journal of medicinal chemistry 2011-01, Vol.46 (1), p.364-369
• Main Authors: Xu, Hui, Fan, Ling-ling
• Format: Article
• Language: English
• Subjects: Antifungal activity; Antifungal Agents - chemical synthesis; Antifungal Agents - chemistry; Antifungal Agents - pharmacology; Cyclization; Fungi - drug effects; Indole[1,2-c]-1,2,4-benzotriazine; Phytopathogenic fungi; Plants - microbiology; Sandmeyer reaction; Triazines - chemical synthesis; Triazines - chemistry; Triazines - pharmacology
• ISSN: 0223-5234; 1768-3254
• DOI: 10.1016/j.ejmech.2010.10.022

A series of novel indole[1,2-c]-1,2,4-benzotriazine derivatives were obtained by a modified Sandmeyer reaction in the presence of tert-butylnitrite (t-BuONO). As compared with hymexazol, a commercially available agricultural fungicide, at the concentration of 50 μg/mL, two indole[1,2-c]-1,2,4-benzotriazines, 5h and 5k, exhibited the more promising and pronounced antifungal activities in vitro against five phytopathogenic fungi. It clearly demonstrated that introduction of appropriate substituents on the indolyl ring of indole[1,2-c]-1,2,4-benzotriazine (5a) would lead to the more potent derivatives. Two indole[1,2-c]-1,2,4-benzotriazine derivatives have been identified as potent antifungal agents and might be considered as novel promising lead candidates for further design and synthesis of agricultural fungicides. [Display omitted] ► Indole[1,2-c]-1,2,4-benzotriazine derivatives were synthesized by a modified Sandmeyer reaction. ► Their antifungal activities were tested against phytopathogenic fungi. ► Two compounds exhibited the promising and pronounced antifungal activities.