Synthesis And Biological Activity Of Nitrogen-containing Myricetin Derivatives

As an effective natural leading compound,myricetin has been reported to show good activities.However,the low bioavailability of myricetin in vivo restricts the application on clinic.In order to improve the activities and bioavailability of myricetin,35 myricetin derivatives were designed,synthesized,and their structures were confirmed by using IR,1H NMR,13 C NMR and HRMS.The Half-leaf method was used to determine the in vivo efficacy of the title compounds against tobacco mosaic virus(TMV),and the results of bioassay showed that some of the compounds exhibited certain anti-TMV activities at the concentration of 500 ?g/mL,Compounds ?4,?6,?9 and ?13 were 60.0,62.5,66.7 and 57.0%,respectively,which were better than that of ningnanmycin(51.8%),and EC50 values were 152.2,99.7,127.1 and 167.3 ?g /m L which better than of ningnanmycin(211.1 ?g /mL)The growth rate method was used to evaluate antifungal activity of all compounds.The result of bioassay showed that some of the compounds had certain antifungal activity.At the reagent concentration of 100 ?g/m L,compound ?1,?2,?3,?4,?6,?9,?13 and ?16 showed inhibition against Xanthomonas oryzae pv.oryzae(Xoo),were 84.9,81.4,84.4,99.6,87.3,77.5,99.4 and 84.3%,respectively,which were better than that of thiediazole copper(52.4%),with EC50 values were 38.6,20.8,34.7,12.9,22.7,27.3,18.3 and 20.1 ?g/mL which better than thiediazole copper(94.9 ?g/mL).At the reagent concentration of 100 ?g/mL,compound ?3,?4,?5,?6,?9,and ?19 showed inhibition against Ralstonia solanacearum(Rs),were 877.5,64.3,75.7,69.3,68.3 and 65.3%,respectively,which were better than that of thiediazole copper(52.4%),with EC50 values were 37.9,72.6,43.6,59.6,60.6 and 39.6 ?g/m L which better than thiediazole copper(131.7 ?g/m L).