A series of quinazolin-4(3H)-one derivatives containing a 1,3,4-oxadiazole thioether moiety were designed, synthesized and evaluated for their biological activities against phytopathogenic microorganisms. Antimicrobial bioassays in vitro indicated that most of the target compounds exhibited more significant antibacterial activities against Xanthomonas oryzae pv. oryzae (Xoo) than the agricultural bactericide thiadiazole-copper. A comparative molecular similarity index analysis (CoMSIA) model with cross-validated q² and non-cross-validated r² values of 0.561 and 0.882 was generated to investigate the structure-activity relationships of title compounds against Xoo. Title compound 6w, which was rationally designed under the guidance of obtained CoMSIA model, exhibited the excellent anti-Xoo effect in vitro with an EC₅₀ value of 29.10 μg/mL, which is approximately 3-folds more effective than thiadiazole-copper (113.93 μg/mL). In addition, compound 6i demonstrated the impressive antifungal effects against Rhizoctonia solani (Rs) and Fusarium graminearum (Fg) in vitro, with the corresponding EC₅₀ values of 11.01 μg/mL and 36.00 μg/mL, which is obviously better than the agricultural fungicide hymexazol (76.74 μg/mL and 56.19 μg/mL, respectively). The above researches indicate that quinazolin-4(3H)-one derivatives containing a 1,3,4-oxadiazole thioether moiety could be further studied as template molecules of novel agricultural microbicides.

设计，合成并评价了一系列含有1,3,4-恶二唑硫醚部分的喹唑啉-4（3 H）-one衍生物对植物致病微生物的生物学活性。体外抗菌生物测定结果表明，大多数目标化合物对米生黄单胞菌（Panthomonas oryzae pv）表现出更显着的抗菌活性。稻米（Xoo）比农用杀菌剂噻二唑-铜。生成具有交叉验证的q ²和非交叉验证的r ²值为0.561和0.882的比较分子相似性指数分析（CoMSIA）模型，以研究标题化合物与Xoo的结构活性关系。标题化合物6w在获得的CoMSIA模型的指导下进行了合理设计，在体外表现出出色的抗Xoo效果， EC ₅₀值为29.10μg/ mL，比噻二唑-铜（113.93μg/ mL）约高3倍。 ）。此外，化合物6i的表现出对令人印象深刻的抗真菌效果水稻纹枯病菌（RS）和禾谷镰刀菌（FG）在体外，与相应的EC ₅₀ 11.01微克/毫升的值和36.00微克/毫升，这显然比农用杀菌剂更好羟甲唑（分别为76.74μg/ mL和56.19μg/ mL）。以上研究表明，喹唑啉-4（3 H）含1,3,4-恶二唑硫醚部分的一种衍生物可以作为新型农业杀微生物剂的模板分子进行进一步研究。