• The Korean Journal of Pesticide Science
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• v.9 no.1
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• pp.108-111
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• 2005

A series of N-[4-cyano-2-fluoro-5-(2-pyrimidinyloxy, 2-benzyloxy or 2-pyridinyloxy)phenyl]-3,4,5,6-tetrahydrophthalimides was synthesized, and the herbicidal activities of those deivatives were evaluated through pre- and post-emergence application under upland conditions in a greenhouse. The results showed that most compounds resulted in stronger herbicidal activity on broadleaf weeds than on grass weeds and higher through post-emergence than pre-emergence application. The N-[(4-cyano-2-fluoro-5-(2-pyrimidinyloxy) phenyl]-3,4,5,6-tetrahydrophthalimide showed the best weed control efficacy and marginal corn safety at a rate of 60 g/ha through pre-emergence application.

• The Korean Journal of Pesticide Science
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• v.10 no.4
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• pp.262-265
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• 2006

A series of N-[4-chloro-2-fluoro-5-(2-(substituted)pyrimidinyloxy)phenyl]-3,4,5,6-tetrahydrophthalimides was synthesized, and the herbicidal activities of those derivatives were evaluated through pre- and post-emergence application under upland conditions in a greenhouse. The results showed that most compounds resulted in stronger herbicidal activities on broadleaf weeds than on grass weeds. The N-[4-chloro-2-fluoro-5-(2-pyrimidinyloxy)phenyl]-3,4,5,6-tetrahydrophthalimide showed the best weed control efficacy and marginal corn safety at a rate of 60 g/ha through pre-emergence application.

• The Korean Journal of Pesticide Science
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• v.7 no.2
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• pp.75-82
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• 2003

We discuss that the growth inhibition activities against root and shoot of rice plant (Oryza sativa L.) and barnyard grass (Echinochloa crus-galli) by N-phenyl-3,4,5,6-tetrahydrophthalimide (A) and N-phenyl-3,4-dimethylmaleimide (B) derivatives with changing substituents can be explained and predicted using comparative molecular field analyses (CoMPA) method. And the results show that the cross-validation value, $q^2$ at three components and Pearson correlation coefficient, $r^2$ were rice plant: shoot; $r^2=0.987$, $q^2=0.387$ & root; $r^2=0.923$, $q^2=0.307$ and barnyard grass: shoot; $r^2=0.902$, $q^2=0.535$ & root; $r^2=0.900$, $q^2=0.450$, respectively. In addition, The activities of unknown compounds were predicted by CoMFA method. From the contour map of (A) derivatives, the selective factors to remove barnyard grass takes positive charge on the benzylic carbon atom (C27), negative charged carbon atom (C29) of meta position and steric bulky groups on the cyclic imino ring (C7-C8).

• The Korean Journal of Pesticide Science
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• v.9 no.2
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• pp.181-184
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• 2005

The heterocyclic PPO inhibitor compounds have been studied due to their potent herbicidal effects without toxic to human and animals. We have designed and synthesized 4,5,6,7-tetrahydroindazole, maleimide, and tetrahydrophthalimide compounds carrying diverse epoxide substituents at 5- position of the phenyl group. Their herbicidal activities were evaluated under submerged paddy conditions. These results showed that 4,5,6,7-tetrahydroindazole compounds gave potent herbicidal activities especially to ECHOR, MOOVA, and CYPSE at a relatively low rate of 16 g/ha and improved tolerance on rice compared to S-275 as a standard herbicide in this experiment.

• The Korean Journal of Pesticide Science
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• v.7 no.2
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• pp.100-107
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• 2003

To improve the growth inhibitory activity against the shoot and root of rice plant (Oryza sativa L) and barnyard grass (Echinochloa crus-galli), a series of N-substituted phenyl-3,4-dimethylmaleimdes derivatives as substrates were synthesized and then their the inhibitory activities of protoporphyrinogen oxidase (1.3.3.4), protox were measured. The quantitative structure-activity relationships (QSAR) between structures and the inhibitory activities were studied quantitatively using the 2D-QSAR method. And also, molecular sharp similarity between the substrate derivatives and protogen, substrare of protox enzyme were studied. The activities of the two plants indicated that barnyard grass had a higher activity than the rice plant and their correlation relationships have shown in proportion for each. Accordingly, the results of SARs suggest that the electron donating groups as $R_2=Sub.X$ group will bind to phenyl ring because the bigger surface area of negative charged atoms in the substrate molecule derivatives may increase to the higher the activity against barnyard grass. Based on the molecular shape similarity, when the derivatives and protogen, subsbrate of protox enzyme were superimposed by atom fitting, the similarity indices (S) were above 0.8 level but the correlation coefficients (r) between S values and the activities showed not good.