摘要：To discover novel strobilurins analogues with good and broad spectrum activity,a series of nove 3,4-dihydro-2H-1,2,4-benzothiadiazine 1,1-dioxides-based strobilurins was designed,synthesized,and tested agains various phytopathogenic *** *** 7k exhibited substantial and broad spectrum antifungal activities against the tested phytopathogenic fungi,especially compound 7b,which showed 100%,80%,90%,and 90%antifungal activity(in virto)against Erysiphe graminis(***),Puccinia sorghi Schw:(P sorghi Schw.)Colletotrichum lagenarium(***),and Pseudoperonospora cubensis(P cubensis)at 300 ug/mL,*** or comparable to the positive control ***,compound 7b exhibited 85%greenhouse *** activity(in vivo)against *** even at 0.2μg/mL,equal to azoxystrobin(90%)and trifloxystrobin(90%)Meanwhile,compound 7b against P cubensis displayed 70%and 55%greenhouse inhibition activity(in vivo)at 1.56 and 0.2μg/mL,respectively,much better than those of azoxystrobin and trifloxystrobin(both 0%at 1.56 and 0.2 ug/mL).Therefore,compound 7b could be considered as the most promising fungicidal candidate for furthe ***,based on the effective concentration(ECso)against ***,the built CoMSIA model provided the useful reference for the further structural optimization design.