Study On Synthesis And Biological Activities Of Benzopyran-4-one

Benzopyrones are a class of compounds which have simple structures but have abundant bioactivities and they are widespread in nature.In recent years,many research groups have carried out extensive research about them.These compounds have many bioactivities such as antifungal activity,antitumor activity,anti-inflammatory activity and the activity of anti-platelet aggregation.Neuchroenin is a kind of novel structure benzodihydropyrone,and now there are few studies about its agriculural activity.Our group is based on its structure to design and synthesis a new class of high-effect agriculural activity compounds.In the thesis,different substituted phenols and acrylonitrile was used as starting material.A series of reactions such as etherification,Friedel-Crafts acylation and ring closure was involved to get original color ketone.Ethyl acetoacetate was undergone carbonyl reduction by sodium borohydride,TBS protection,and dibal-H reduction to get 3-hydroxy-n-butyraldehyde.Finaly,five target compounds were synthesized through aldol condensation between original color ketone and 3-hydroxy-n-butyraldehyde,and DMP oxidation.The five compounds have not been reported in research papers.Their structures were characterized by 1H NMR,IR and MS,respectively.Antibacterial activity was assayed by using seven kinds of plant pathogenic through growth rate method under the test concentration was 50 mg/L.The result showed that some compounds had better inhibition to the tested plant pathogens.The inhibition rates target compounds w-2 and w-3 on Fusarium coeruleum of were 78.0%and 77.3%,and the rate on Alternaria alernaa were 89.0%and 100.0%.Inhibition rates of compounds w-3 and w-1 on germ Curvularia lunata were 78.6%and 76.3%respectively.Inhibition rate of compounds w-5,w-2,w-1 and w-3 on Alternaria solani transcended 75%.Compounds whose inhibition rate was higher than 75%was selected to further determine their EC50.The result showed that EC50 values of w-5,w-2,w-1 and w-3 on Alternaria solani were 8.4,1.9,7.9,11.4 which less than positive control triabendazole EC50 18.1.EC50 of w-3 on Alternaria alternate was 10.5 and it was also less than the positive control 10.9.Herbicidal activity of w and wq series compounds was undergone through seed germination method,and their toxicity on fifth instar armyworm was measured by using oral injection method.The result showed that the inhibition target compounds have some effect on germination of weed seeds and lethal capability on armyworm,but lethal capability was less than 40%.