Synthesis And Biological Activities Of Pesticide Lead Compound

In order to research and find new pesticide lead compouds, In this paper, "substructure link way" was adopted to devise and synthesize sixty five new compouds by chrysanthemyl respectively linking with chloramphenical, tebucona -zole,l-phenyl-3-hydroxyl-l,2,4-triazol,3,5,6-trichloro-2-pyridinol, fipronil, 1-arylp -yrazole and thiazol-2-amine. Those structures of new products obtained were confirmed by MS and ~1H-NMR spectroscopy. The biological activities of the newly synthesized compounds were also studied, in which some of them were found to show good insecticidal, fungicidel or herbicidal activities. The general formula of new chemicals synthesized were described as follow:Formular IThe results of bioassay screening indicated that, l-phenyl-lH-l,2,4-triazol-3-yl2, 2-dimethyl-3-(2-methylprop-1-enyl)cyclpropanecarboxylate(3a) showed show good insecticidal, fungicidel and herbicidal activities;l-phenyl-lH-l,2,4-triazol-3-yl3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylate(3b) showed show good insectic -idal and fungicidel activities. Compoud 3a and 3b might be pesticide lead compounds.Formular IIRO-CH2-CH-NHC-CH HO-CH ClN02 4a"4e 5a-5eR same as Formular IThe results of bioassay screening indicated that, 2-(2,2-dichloroacetamido) -3-hydroxy-3-(4-nitrophenyl)propyl2,2-dimethyl-3-(2-methylprop-l-enyl)cyclopropa necarboxylate(4a) and 3-((lH-l,2,4-triazol-l-yl)methyl)-l-(4-chlorophenyl)-4,4- dim ethylpentan-3-yl3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylate(5b) showed good activity againt Echinochloa crus-gali and Brassicanapus L., can be herbicidal lead compound. The compoud which gained from tebuconazole linked with chrysanthemyl had lower fungicidel activity than tebuconazole, can not be fungicidel activity lead compound. At 600mg/L, 2-(2,2-dichloroacetamido)-3-hydroxy-3-(4-nitrophenyl)propyl2-(4-chlorophenyl)-3-methylbutanoate(4d), (S)-3-((l H-1,2,4-triazol-1 -yl)methyl)-l -(4-chlorophenyl)-,4-dimethylpentan-3-yl2,2-d imethyl-3-(2-methylprop-1 -enyl)cyclopropanecarboxylate(5a) and (S)-3-((lH-1,2,4 -triazol-1 -yl)methyl)-1 -(4-chlorophenyl)-4,4-dimethylpentan-3-yl2-(4-chlorophenyl)-3-methylbutanoate(5d) showed 66.45%, 83.83%, 71.22% restraining activity againt Aphis fabae. The germicide became a new insecticidal compoud by substructure link way. The study proved a useful revelation and an effective direction for the further related work.Formular III0F3C-S NHR6a-6eR same as Formular IThe results of bioassay screening indicated that, the series compoud of 6a-6e show high activity againt Plutella xylostella Linnaeus and Aphis fabae. Based work of general screening, we put up the work of particular screening. The results corroborate that the series compoud of 6a-6e had high insecticidal activity. The LC50 of N-(3-cyan o-1 -(2,6-dichloro-4-(trifluoromethyl)phenyl)-4-(trifluoromethylsulfinyl)-1 H-pyrazol-5-yl)-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxamide(6b) was 15.1 mg/L. Also it is middling toxicity. Compoud 6b can be a high activity pesticide lead compound. At 500mg/L, 2-(4-chlorophenyl)-N-(3-cyano-l-(2,6 -dichloro-4-(trifluoro methyl)phenyl)-lH-pyrazol-5-yl)-3-methylbutanamide(7d) showed 90% restraining activity againt Echinochloa crus-gali, might be herbicide lead compound. Formular IV8-14R same as Formular I 4-CH3Ph, 4-CH3C0(K 4-C2H5COOCH2> 5-NO2The results of bioassay screening indicated that, compounds 10a and lOd achiev -ing synergistic effect, showed good insecticidal and fungicidel activities, might be pesticide lead compound. Compounds lOd, 13a, 13d, 14a, 14b, 14c, 14e showed 100% restraining activity againt Plutella xylostella Linnaeus, can be insecticidal lead compound. According the results and compounds' structure, we knew: ethyl-2-(2-aminothia zol-4-yl)acetate and 5-nitrothiazol-2-amine were none insecticidal activity. But the new compounds which found from them linking with chrysanthemyl were high activity. It showed we achieve synergistic effect by substructure link way. The study proved a useful revelation and an effective direction for the further related work.