Synthesis And Biological Activity Of 1,4-pentadien-3-one Derivatives Containing Phosphite

Penta-1,4-diene-3-ones,as an important analog of curcumin,have been widely used in pharmaceuticals and agrochemicals due to their extensive biological properties,including antiviral,antibacterial,anti-inflammatory,anticancer,anti-oxidative,and insecticidal activities.In recently,many papers have been reported about their antiviral activities against plant viruses.Meanwhile,phosphate and their derivatives posses a wide range of biological activities,such as insecticidal,antiviral and antibacterial activities,and also play an important role in the field of pesticide application.In addition,we found that after the introduction of the phosphates in the structures,the water solubility of the compounds were greatly improved.Motivated by the above-mentioned findings,39 penta-1,4-diene-3-one derivatives bearing phosphate groups,were designed and synthesized.And their structure were confirmed by ¹H NMR,¹³C NMR,³¹P NMR and HRMS.The main work and findings are summerized bellow:Based on the half leaf blight spot method,at concentration of 500μg/mL,using the commercial agent ningnanmycin as the control,The antiviral activities against tobacco mosaic virus（TMV）were tested.Among these,compounds A3,A6,B1,B3,B14 and B21 exhibited excellent curative activities against TMV,with the inhibitory rates of 62.5,62.8,61.2,62.2,69.3 and 63.4%,respectively,which were exceeded ningnanmycin（56.1%）.The protective activities of compounds A5,A18,B10,B12and B18 were 58.6,58.9,66.7,63.8 and 58.8%,respectively,which were more potent than that of ningnanmycin（56.2%）.Further biological assay indicates that the curative activities of compound A18,B10 and B12,with corresponding EC₅₀ values of 291.2,104.2 and 290.0μg/mL,which were more potent than that of ningnanmycin（297.1μg/mL）.The protective activities of compounds A6,B1,B14 and B21,with the EC₅₀ values 234.0,270.0,238.8 and 250.0μg/mL,which were superior to that of ningnanmycin（386.2μg/mL）。The antibacterial activities of the target compounds against two phytopathogenic bacterial（Xoo and Xac）were tested in vitro by the turbidimeter test.Commercial agricultural antibacterial bismertiazol（BT）and thiodiazole-copper（TC）were used as references.Most of the title compounds exhibited better antibacterial activities against Xoo and Xac at 100 or 50μg/mL.Several of the compounds showed excellent activities against Xoo compared to TC and BT.Among these,the antibacterial activities of compounds A3,A12,A13,A15,B1,B9,B10 and B12 against Xoo at 100μg/mL were 94.9,88.1,85.3,90.8,85.0,100.0,86.5 and 85.5%,respectively,exceeding those of both TC（50.2%）and BT（64.9%）.The antibacterial activities of compounds A3,A5,A7 and A15 against Xac at 100μg/mL were 90.3,90.2,90.2 and99.5,respectively,which were superior to those of TC（57.2%）and BT（70.3%）.Further biological assay indicates that the EC₅₀ values of compounds A3,A4,A11,A12,A13,A15,B1,B9,B10 and B12 against Xoo were 22.9,6.7,16.5,11.4,26.5,36.1,35.8,8.6,19.1 and 17.7μg/mL,which were much better than those of BT（58.8μg/mL）and TC（78.7μg/mL）.Compounds A3,A5,A7,A15 and B7 exhibited excellent antibacterial activities against Xac,with EC₅₀ values of 10.6,22.1,18.4,10.8 and 22.9μg/mL,which were significantly superior to those of BT（44.5μg/mL）and TC（88.0μg/mL）.