Synthesis And Primary Biological Activity Studys Of Fluorophenyl-pyrimidinyl Urea Derivatives

Most of unsymmetrical substituted ureas are kinds of compounds with diverse biological activity. Because their structure contains a peptide bond, they are widely used for insecticide, fungicide, herbicide and plant growth regulator. The development trend of future pesticide is super high effectivity, low toxicity, no residue and good environmental compatibility. Fluorine atom has simulative, osmotic, electronic and obstructive function, and the structure of pyrimidine ring is simple and particular mode of action. In this paper, the benzene ring containing fluorine atom or trifluoromethyl was introduced to the N atom of urea bridge, and the substituted pyrimidine ring was leaded into the other N atom of urea bridge.32 urea compounds were synthesized. Thereinto, sixteen of which were novel compounds. Their structures were confirmed by melting point, IR and'HNMR. At the same time, the primary biological activity of target compounds were also studied. The main contents of study as following:I Synthesis and characterization of fluorophenyl-pyrimidinyl urea derivativesThe synthetic method of ureas generally phosgene-based isocyanates, intermediate isocyanate was directly used to react with pyrilamine to product target compounds without further purification. This synthesis method was simple, safe and easy to fix on quantity. IR and'HNMR were adopted to define the compounds'structure. The structures of urea derivatives were shown as following: 1 R,=2-CF3. RzJlfOCH^ Rp3-Oyi2,Rf<)CH33 Ri=2-F, RaRj=OCHs4 Rr^JRaJ^OCH^ R,=3-CF3, Rf^RK^ R,=2-F,R-KH3Rf-a9 Ri=3-F, R|=2-CF3. Rf^RfOH;^ RpJCFi Rp€H3R3=OH;13 R=2-F, Rj-}3R3=-OH;14 R, 3-F,Rf--CH3R-0R;15 R_r--CHAR,, -OR16 R, 2-CF3,3, 17 R,=2-CF3, R^r-CHi 17 R1=3-CF3, RaflHt 23 R,=2-F, R^Rf-H; 24 R,=3-F, R^H; 25 R^H^ R:OCH3. R^-027 R,=2-F, RfMXH3.R3M33Rr2<T3,Rf<X^3RH^9Ri=3<T3,Rf<)CH3R3<130Ri^-F; 31 Rf=2-CF3; 32 Ri=3-CF3II The preliminary biological activity test"The seeding root law" and "Petri dish testing for herbicidal bioactivity" were respectively adopted to test the plant growth regulating, herbicidal activities of target compounds with the concentration of 10,25,50,100 and 200 mg/L.The preliminary bioassay results showed that:The optimal concentration of most compounds was 10 mg/L. on this concentration, compounds 3,4,8,11,23,27 and 28 in promoting growth rate were 80% for rice, as well as compounds,12,13,22 and 31 in promoting growth rate were 75% for rape, Simultaneously, the promoting effect on the stem was better than the root; For amaranthus albus L, the inhibitory effect on the root was better than the stem, the inhibition rate of root length of some compounds reached up to 100%. on the concentration 100 mg/L, the inhibition rate of compounds 4,10,13 and 27 were more than 30%. The weeding effect was better. However, the inhibitory effect on the stem was better than the root of pennisetum, the inhibition rate of stem length reached up to 90%, the inhibition rate of root length was only 50%, compound 16 and 20 stronge herbicidal activity of amaranthus.