Synthesis And Biological Activity Of Pentadienone Oxime Ether Derivatives Containing Pyridine

As important curcumin analogs,penta-1,4-diene-3-ones have been widely researched and used in medicinal and agrochemical development because of their extensive biological properties,including antibiotic,anticancer,anti-oxidative,antiinflammatory,antiviral and insecticidal activities.Notably,their visible antiviral activities against plant viruses have been reported well in recently.Meanwhile,oxime ethers have played vital roles in agrochemical development due to their outstanding characteristics,including high activity,unique action mechanism and broad spectrum.Considering these above findings,series of penta-1,4-diene-3-one oxime ether derivatives bearing pyridine,4(3H)-quinazolione or coumarin groups,which confirmed by IR,1H NMR,13 C NMR and HRMS(ESI-MS),were designed and synthesized through introducing oxime ether groups to the 3-position of penta-1,4-diene-3-one.My main work and findings are summerized bellow:1.Eighteen penta-1,4-diene-3-one oxime ether derivatives bearing pyridine moiety were designed and synthesized in the present work.Using the commercial agent ribivirin as the control under the same conditions,their antiviral activities against tobacco mosaic virus(TMV)were tested at concentration of 500 ?g/mL based on the half leaf blight spot method.In terms of their curative activities,the compounds A1,A2,A3,A7,A8,A10,A15 and A16 exhibited visible antiviral activity against TMV,with the inhibitory rates of 45.5,40.3,49.4,43.1,39.8,45.1,54.6 and 47.6%,respectively,which are better than ribivirin(36.2%).In terms of their protective activities,the inhibitory rates of compounds A1,A5,A12,A15 and A16 were 58.5,54.4,59.9,70.2 and 60.3%,respectively,which are better than that of ribivirin(53.4%).Moreover,the compounds A15 and A16 effectively inactivated TMV,with the inhibitory rates of 86.8 and 78.1%,which are better than ribivirin(77.3%).Further biological assay indicates that the EC50 values of compound A3,A10,A15 and A16 in terms of their curative activities were 274.8,299.2,251.8 and287.7 ?g/mL,which are better than that of ribivirin(379.8 ?g/mL).2.Seventeen penta-1,4-diene-3-one oxime ether derivatives bearing 4(3H)-quinazolione moiety were designed and synthesized in the present work.Using the commercial agent ningnamycin as the control under the same conditions,their antiviral activities against TMV were tested at concentration of 500 ?g/mL based on the half leaf blight spot method.In terms of their curative activities,the compounds B3,B4,B5,B10,B11 and B16 exhibited visible antiviral activity against TMV,with the inhibitory rates of 55.9,53.4,54.6,55.4,59.1 and 53.5%,respectively,which are better than ningnamycin(51.8%).In terms of their protective activities,the inhibitory rates of compounds B3,B10 and B11 were 69.8,67.7 and 72.0%,respectively,which are better than that of ningnamycin(65.7%).Further biological assay indicates that the EC50 values of compound B3,B10 and B11 in terms of their curative activities were 138.5,132.9 and 125.6 ?g/mL,which are better than that of ningnamycin(207.2?g/mL).3.Five penta-1,4-diene-3-one oxime ether derivatives bearing coumarin moiety were designed and synthesized in the present work.Using the commercial agent ribivirin as the control under the same conditions,their antiviral activities against TMV were tested at concentration of 500 ?g/mL based on the half leaf blight spot method.In terms of their curative activities,the compounds C3,C4 and C5 exhibited visible antiviral activity against TMV,with the inhibitory rates of 38.9,38.8 and42.5%,respectively,which are better than ribivirin(36.2%).4.Using the commercial agents bismerthiazol as the control under the same conditions,the antibacterial activities of some title compounds against tobacco bacterial wilt and Xanthomonas oryzae pv.oryzae at concentration of 100 and 50?g/mL were evaluated based on the turbidimeter test.The bioassay indicated that these compounds exhibited moderate antibacterial activity against the tested bacterial stains at concentration of 100 and 50 ?g/mL,which are inferior to bismerthiazol.