Synthesis And Fungicidal Activities Of The Aryl Goup Imidogen Thiadiazolinlyl Spiro Hydrocarbon

In order to study alicyclic sizes and substituted groups attached in the ring on the fungicidal activities of macrocyclic thiadiazolinederivatives, three new classes of compounds, I, II and HI were designed and synthesized. Seventeen compounds that not reported in literatures were obtained from cyclohexanone and cyclododecanone as starting materials by condensation with substituted thiosemicarbazones and then ring formatted with MnO2.All of the compounds was confirmed by H NMR, 13C NMR and elemental analysis in the paper. Two of the compounds were suitable for X-ray crystal structure analysis through which the configurations and stereo-structures of the products were confirmed. And this would contribute to the study on structure-activity-relationship of these compounds.The original fungicidal activities results showed that compounds I exhibited fungicidal activities to Rhizoctonia solani Kuhn and Veticillium dahlide at the concentration of 100 and 50mg/L. At the concentration of 50mg/L, the inhibited yields of five of the compounds I attained to 90% especially to Rhizoctonia solani Kuhnthere while the fungicidal activities of compounds II, III are lower. The original experimental results showed that the fungicidal activities of these compounds would be improved when 12-membered ring of the molecular was substituted by 6-membered ring while the fungicidal activities of the derivatives of a-substituted cyclododecanonal thiadiazoline were equal or reduced more of less compared to that of the parent cyclododecanonal thiadiazoline compounds. The results showed that the parent ring exhibited significant effects to the fungicidal activities of these compounds while the substituted groups exhibited a little effects.