Synthesis And Primary Biological Activity Tests Of Fluorobenzoylthioureas Derivatives

Benzoylthioureas are kinds of compounds with diverse biological activities, they have been used as fungicide, herbicide. insecticide and plant growth regulator, owing to simulative. electronic. obstructive and osmotic function of flourine atom, It will greatly increase biological activities of Benzoylthiourea compounds, high efficiency and low toxicity, in favor of environmental protection if fluorine atoms or groups are introduced to the benzoylthiourea. Therefore, Fluorine-containing pesticides is becoming a hot development. Up to now, in the world more than 1300 pesticides, fluorinated pesticides accounted for more than 12%. In fluorinated pesticides, herbicides account for 45%, pesticides 33%, fungicides 15%, others 7%.In this study, flourine atoms were introduced to the Benzoylthiourea compounds, 13 novel compounds were synthesized. Their structures were confirmed by infra-red spectrum. GC-MS. ~1HNMR and elementary analysis. In order to study primary biological activities of target compounds, pot experimental method was used in this test. The structure-activity relationship was studied. The main contents were as follows:I The synthesis of fluorobenzoylthioureasThe target compounds have been synthesized by the reaction of substitutional 2-amino Pyrimidine and Pyridine with fluorobenzoyl isosulfocyanic ester from fluorocarboxylic acid by chloration and acylate. The process of the synthesis used trithylamine as HCl scavenger. The result showed that this synthetical method is safe, convenient, easy to fix on quantity and easy to control.II The study of addition reaction conditionsThe representative target compounds of three series were selected in this study. By changing the addition reaction time and calculating the yield of target compounds, in order to determine the better reaction time. III The preliminary biological activity testsThe preliminary biological activity tests were carried out at the concentration of 400 mg/L. 100 mg/L. 10 mg/L and 1 mg/L. the test crops included dicotyledon such as rape and monocotyledon such as rice, the test weeds included dicotyledon such as amaranthus albus L and monocotyledon such as Bermudagrass.Preliminary biological activity results show that: with the different concentration of pharmaceutical and plant species, biological activity is different. Target compounds demonstrated inhibitory activity against the survival rate. stem. root and weight of rape at high concentration and promotion activity at low concentration, except compounds 1 and 2 which promoted the survival of rape at any concentration, compound 11 promoted weight of rape and compound 13 promoted stem and root of rape at any concentration; Target compounds had little effect on survival of rice, they demonstrated inhibitory activity against the stem. root and weight of rice. compound 1 promoted the stem and weight of rice at any concentration, compound 6 and 12 promoted the stem and root of rice at any concentration; Target compounds demonstrated inhibitory activity against survival rate and weight of amaranthus albus L basically, with the increasing concentration of compounds, the inhibitory effect enhanced, compounds 3 and 7 promoted the survival rate and weight of amaranthus albus L at the concentration of 1 mg/L, compound 8 just promoted the weight of amaranthus albus L at the concentration of 1mg/L; Target compounds demonstrated inhibitory effect on the survival rate and weight of Bermudagrass basically, further more, with the increasing concentration of compounds, the inhibitory effect enhanced, only 6.7.8 and 9 promoted the weight of Bermudagrass at low concentration.IV The study of structure-activity relationshipIn order to study the relationship between structure parameter of compounds and biological activities, the PM3 method in Gaussian03 package was accepted to do the quantum chemistry calculation based on the activity datas of three types of target compounds, and the potential active sites were discussed.