Synthesis And Biological Evaluation Of Novel Triazolinone Protoporphyrinogen Oxidase Inhibitors

Triazolinone derivatives are one of the important families in heterocyclic compounds, which have been found to have widespread biological activities, especially as herbicides. Over the past twenty years, they have become one of the Pesticide researchers’hot topics. Triazolinone derivatives are also a kind of important herbicides with protoporphyrinogen oxidase (PPO) enzyme as the targe. Considering of our group’s previous research work and according to the method of the bioisosterism and the active structural stitching, we further transform and synthesis a series of novel compounds in this paper. By introducing sulfonamide, lipid amide and oxygen bridge connecting aromatic amide and other active substructure units, we a series of compounds that never been reported in literatures, and the biological activity tests were carried out to study its biological activity. The specific research works are as follows:1. Generally summarize triazolinone derivatives’biological applications.2.41novel triazolinone derivatives were synthetized. All novel compounds are characterized by1H NMR and ESI-MS and elemental analysis.3. The in vitro PPO inhibition of these novel target compounds were assayed, and the bioassay results indicate that:although some of the compounds, such as Y12299and Y12296, on tobacco and human PPO showed some selectivity, but most compounds’ activity were not good.In the structure of triazolinone derivatives containing sulfonamide and amide structure with sulfur bridge, the better of Y12168, Y12298and Y12299on tobacco PPO Ki values were0.11μM,0.65uM and0.14μM. And activity test of triazolinone derivatives connecting the ester and aryl amide structure by oxygen,Y12450, Y12454and Y12458show some better activity, whose Ki values on the tobacco and human PPO were0.690μM and4.771μM,0.525μM and2.601μM,0.048μM and2.046μM.4. Some of the compounds have been tested their in vivo herbicidal activity and crop safety by the greenhouse pot experiment, results show that:the compound of Y13060at a dose of150gai/ha showed good inhibition rate; at a dose of37.5gai/ha, compound Y12158still show the crop safety good.