The Synthesis And Biological Activity Of 1,2,3-thiadiazole Based Tetrazole Derivatives

Plant elicitor is one of the most significant new directions of the plant protection in the 21st century by effective controlling of disease caused by fungi and virus.The commercialized plant elicitors including benzo[1,2,3]-thiadiazole(BTH),tiadinil(TDL)and methiadinil which was discovered by Nankai University under the commercialization were all derivatives of 1,2,3-thiadiazoles.Thirty five novel tetrazole derivatives of 1,2,3-thiadiazole have been designed and synthesized on the basis of former studies on the development of novel plant elicitors using the principle of isosteric for biological activity including fungicide and anti-virus activity screening,all the structures of the target compounds have been characterized by 1H NMR,IR and HRMS.Biological activity screening indicates that,compound 1-18 exhibit excellent wide spectrum of fungicide activity in this series at at the concentration of 50?g/mL.Three compounds including I-15,I-26 and I-35 shows good insecticide activity and anti-virus activity at the concentration of 100?g/mL with inhibition of Protection,Curative,Inactivation and Induction.1-15 in the four modes of inhibition were 29.5%,42.86%,29.12%,47.22%;compound 1-26 the inhibition rates were 30.65%,49.73%,29.12%,30.65%;Compound 1-35 inhibition rates were 27.97%,47.62%,37.54%and 42.36%,respectively.Structure activity relationship studies indicate that,the target compounds at aromatic rings with methyl,hydroxyl,triflouromethyl,methoxyl and hologen improve their bioactivity.Studies of this thesis indicate that,some target compounds with good fungicide activity also show good systemic acquired resistance,this provides the basis for the development of novel fungicide with good systemic acquired resistance.