Novel Pyridyl-Oxazole Carboxamides: Toxicity Assay Determination in Fungi and Zebrafish Embryos.

Eight novel pyridyl-oxazole carboxamides were evaluated against fungi and displayed good fungicidal activities against and . Preliminary bioassay results indicated that at 100 mg/L, compounds -, and exhibited 100% fungicidal activities against , and the compound to at 100%. Then, the zebrafish embryo acute toxicity test was performed to assess the toxicity of and .

1,2,4-Oxadiazole-Based Bio-Isosteres of Benzamides: Synthesis, Biological Activity and Toxicity to Zebrafish Embryo.

To discover new compounds with broad spectrum and high activity, we designed a series of novel benzamides containing 1,2,4-oxadiazole moiety by bioisosterism, and 28 benzamides derivatives with antifungal activity were synthesized. These compounds were evaluated against four fungi: , , , and . The results indicated that most of the compounds displayed good fungicidal activities, especially against .

Synthesis and Biological Activity of Benzamides Substituted with Pyridine-Linked 1,2,4-Oxadiazole.

To find pesticidal lead compounds with high activity, a series of novel benzamides substituted with pyridine-linked 1,2,4-oxadiazole were designed by bioisosterism, and synthesized easily via esterification, cyanation, cyclization and aminolysis reactions. The structures of the target compounds were confirmed by H-NMR, C-NMR and HRMS. The preliminary bioassay showed that most compounds had good larvicidal activities against mosquito larvae at 10 mg/L, especially compound , with a larvicidal activity as high as 100%, and even at 1 mg/L was still 40%; at 50 mg/L, all the target compounds showed good fungicidal activities against the eight tested fungi.