- Research on controllable degradation of sulfonylurea herbicides
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In order to seek ecologically safer and environmentally benign sulfonylurea herbicides (SU), insight into the structure/bioassay/soil degradation tri-factor relationship was first established. With the introduction of various groups (alkyl, nitro, halogen, cyano etc.) at the 5th position of its benzene ring, structural derivatives of chlorsulfuron were designed, synthesized, and evaluated for their herbicidal activity. The structures of the title compounds were confirmed by infrared spectroscopy, ultraviolet spectroscopy, 1H and 13C NMR, mass spectrometry, elemental analysis and X-ray diffraction. Bioassay results confirmed that most derivatives retained their superior herbicidal activities in comparison with chlorsulfuron. After investigating the soil degradation behavior of each molecule under set conditions, it was found that structures with electron-withdrawing substituents at the 5th position of the benzene ring retained their long degradation half-lives, yet the introduction of electron-donating substituents accelerated the degradation rate. These results will provide a valuable clue to further explore the potential controllable degradation of SU and other herbicides, and to discover novel herbicides that are favorable for environmentally and ecologically sustainable development.
- Hua, Xue-Wen,Chen, Ming-Gui,Zhou, Shaa,Zhang, Dong-Kai,Liu, Ming,Zhou, Sha,Liu, Jing-Bo,Lei, Kang,Song, Hai-Bin,Li, Yong-Hong,Gu, Yu-Cheng,Li, Zheng-Ming
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p. 23038 - 23047
(2016/03/12)
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- Herbicidal compositions with increased crop safety
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Disclosed are herbicidal concentrate formulation compositions having reduced grass crop plant phytotoxicity comprising certain sulfonamide or sulfonylurea herbicides in admixture with a non-herbicidal organic or inorganic acid or mixture thereof in an amount sufficient to insure that during the post-emergent agricultural uses thereof in water diluted form the pH of the mixture is below about 5; also disclosed is the preparation of said compositions, aqueous formulations of said concentrate and the use of said formulations.
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- Herbicidal heterocyclic sulfonylurea compositions safened by herbicidal acids such as 2,4-D below a pH of 5
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Disclosed are herbicidal concentrate formulation compositions having reduced grass crop plant phytotoxicity comprising certain sulfonamide or sulfonylurea herbicides in admixture with a herbicidal organic acid from the group consisting of clopyralid, 2,4-D, 2,4-DP, dicamba, dichlorprop-P, fluroxypyr MCPA, MCPP, mecoprop-P, picloram, triclopyr or mixtures of said acids; also disclosed is the preparation of said compositions and the pre- and post-emergent agricultural uses thereof in water diluted form.
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- Soybean plants with dominant selectable trait for herbicide resistance
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The utilization of a positive selection seed screening process to isolate rate variants with resistance to a herbicide is described. The ability to screen large numbers of mutagenized seed has made it feasible to pursue and isolate plants with low frequency dominant herbicide-resistance mutations. The dominant herbicide resistance mutations are useful for many applications including expanding the utility of sulfonylurea herbicides for soybean weed control, production of F1 and F2 seeds, and as selectable markers for efficient seed purification.
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- N-phenylpyrrolidines
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The 1-(3,5-bis-trifluoromethylphenyl)-2-thioxopyrrolidine-4-carboxylic acid derivatives of the formula I below are suitable for protecting crop plants against the phytotoxic action of herbicides and for regulating the plant growth. The 1-(3,5-bis-trifluoromethylphenyl)-2-thioxopyrrolidine-4-carboxylic acid derivatives are those of the formula I STR1 wherein A is --COOR1, --COSR1, --COO? M≈, --CONR2 R3 or --COCl; R1 is hydrogen, C1 -C4 alkyl, C2 -C6 alkenyl or C2 -C6 alkynyl; R2 and R3 independently of one another are hydrogen, C1 -C4 alkyl or C3 -C7 cycloalkyl; or R2 and R3 together with the nitrogen atom to which they are bonded are a saturated 3- to 7-membered heterocycle which can contain an additional hetero atom selected from the group comprising O, N and S and which is unsubstituted or up to trisubstituted by C1 14 C4 alkyl; and M≈ is the equivalent of an alkali metal cation or an alkaline earth metal cation or HN≈ (R2)3, and their isomers in optically pure or enriched form.
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- Herbicidal compound concentrate
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There is provided a novel herbicidal compound concentrate in the form of compressed solid formulations that disintegrate in water to form a sprayable dispersion.
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- Herbicidal complexes with ureas
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Water-soluble complexes, which have herbicidal utility, can be formed from urea and alkali metal salts of selected sulfonylureas, e.g., chlorsulfuron.
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- Process for preparing sulfonylureas
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Sulfonylureas are prepared by contacting a sulfonyl halide with an ammonium, phosphonium, sulfonium, or an alkali metal cyanate salt in the presence of an amine.
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