共查询到18条相似文献,搜索用时 15 毫秒
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Yukio Nezu Masahiro Miyazaki Kazuhiko Sugiyama Nobuhide Wada Ikuo Kajiwara Takeshige Miyazawa 《Pest management science》1996,47(2):115-124
A new series of the O-pyrimidinylsalicylates was synthesized and their herbicidal activity was examined. Some of these compounds showed very strong herbicidal activity under pre- and post-emergent treatment conditions against various kinds of grass and broadleaf weeds. Among these compounds, O-(4, 6-dimethoxypyrimidin-2-yl) salicylic acid and its methyl ester were found to exhibit the highest activity. The herbicidal symptoms observed after the treatments included early cessation of plant growth followed by chlorosis, necrosis and plant death. The symptoms were similar to those caused by sulfonylureas and imidazolinones, which inhibit branched-chain amino acid biosynthesis. 相似文献
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Maria J. Gil Jos M. Zabalza Javier Navarro Maria A. Maú Alberto Gonzlez Víctor Martínez Merino Arantxa Canal Mercedes Royuela Pedro M. Aparicio-Tejo 《Pest management science》1997,49(2):148-156
Several ethyl 2,3-dihydro-3-oxoisothiazolo[5,4-b]pyridine-2-alkanoate derivatives were synthesized as herbicides. Only 5-methyl derivatives inhibited both hypocotyl and root growth in the lettuce (Lactuca sativa L.) seedling test at 100 mg litre-1. Only ethyl propionate and valerate derivatives showed significant inhibition at 0·1 mg litre-1, whereas ethyl acetate or butyrate derivatives were inactive. Contrary to unoxidized derivatives, the inhibitory effect of 1-oxide and 1,1-dioxide derivatives was strongly dependent on concentration; ethyl 2,3-dihydro-5-methyl-3-oxoisothiazolo[5,4-b]pyridine-2-propionate 1,1-dioxide inhibited 100% of germination at 100 mg litre-1 and 45% of lettuce seedling growth at 0·1 mg litre-1. Quantitative structure–inhibition of growth relationship analysis carried out by adaptive least-squares (ALS) method gave a good correlation with small and hydrophobic 5-substituents as well as with odd carbon-chain ethyl alkanoates in position 2. Active compounds did not show auxin-like activity from 0·1 to 100 mg litre-1. © 1997 SCI. 相似文献
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Barbosa LC de Alvarenga ES Demuner AJ Figueiredo R da Silva AA 《Pest management science》2003,59(9):1043-1051
Several new compounds with potential herbicidal activity were synthesized from 2alpha,4alpha-dimethyl-6,7-exo-isopropylidenedioxy-8-oxabicyclo[3.2.1]octan-3-one (4). Seven aromatic alcohols were prepared by reaction of (4) with aryllithium reagents, where the aryl groups were 4-ethoxyphenyl (5, 70% yield), 4-ethylphenyl (6, 82% yield), 4-butylphenyl (7, 78% yield), 4-tert-butylphenyl (8, 81% yield), 2,4-dimethoxyphenyl (9, 75% yield), 2-ethylphenyl (10, 12% yield) and para-(4-bromophenoxy)phenyl (11, 24% yield). Reaction of the acetonide (4) with Grignard reagents formed also four aliphatic alcohols where the alkyl groups are ethyl (13, 78%), butyl (14, 85%), hexyl (15, 81%) and octyl (25, 92%). The alcohols (5), (6), (7), (8), (13), (14), (15) and (25) were reacted with thionyl chloride in pyridine, forming their respective alkenes (17, 76%), (18, 74%), (19, 83%), (20, 73%), (22, 78%), (26, 62%), (23, 77%) and (24, 66%). The effect of these compounds, at the concentration of 5.5 microg g(-1), on the development of radicle and aerial parts of Sorghum bicolor (L) Moench, Euphorbia heterophylla L, Brachiaria decumbens and Desmodium tortuosum DC was evaluated. 相似文献
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Petri dish bioassays, based on root response of corn grown in soil or in perlite, were used to study the activity, adsorption,
mobility and field persistence of sulfosulfuron in a silty clay loam and a sandy loam soil. Both bioassays indicated that
activity of sulfosulfuron increased with increasing herbicide concentration, and to a slightly greater degree in sandy loam
soil than in silty clay loam soil. More sulfosulfuron was adsorbed on the sandy loam (not biologically available) than on
the silty clay loam soil. Consequently, slightly greater amounts of sulfosulfuron were leached through the silty clay loam
than through the sandy loam soil. Biologically available sulfosulfuron was not detected at depths below 40 cm after application
in sandy loam, but this was not the case for the silty clay loam soil. In 2002, all sulfosulfuron rates showed field persistence
of less than 5 months. On the other hand, in 2003, biologically available sulfosulfuron was detected in the 0–10-cm soil depth
150 days after application.
http://www.phytoparasitica.org posting May 6, 2004. 相似文献
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Masatoshi Tamaru Takayoshi Takehi Naoshi Masuyama Ryo Hanai 《Pest management science》1996,47(4):327-335
The method reported previously (Part I) was employed to prepare a variety of novel 6-acylsalicylates as key intermediates. 6-Acylpyrimidin-2-yl salicylates (2-acyl-6-[(4,6-disubstituted pyrimidin-2-yl)oxy]benzoate derivatives: Type 1), the closely related phthalide compounds (3-alkyl-7-[(4,6-dimethoxypyrimidin-2-yl)oxy]phthalide derivatives: Type 2) and the ketal derivatives of 2-acyl-6-[(4,6-dimethoxypyrimidin-2-yl)oxy]benzoates (Type 3) were synthesized and their herbicidal activities measured. Methyl 2-acetyl-6-[(4,6-dimethoxypyrimidin-2-yl)oxy]benzoate gave excellent control of barnyard grass with a promising profile as a prototype rice herbicide. 相似文献
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Sergey V. Popkov Leonid V. Kovalenko Mikhail M. Bobylev Oleg Yu. Molchanov Miron Z. Krimer Valery P. Tashchi Yury G. Putsykin 《Pest management science》1997,49(2):125-129
A number of substituted 2,2-dimethyl-6-arylidene-1-triazol-1-ylmethylcyclohexanols and 2,2-dimethyl-6-arylidene-1-imidazol-1-ylmethylcyclohexanols were prepared from 2-methylcyclohexanone in four steps: Claisen–Schmidt condensation with substituted benzaldehydes, methylation of the resulting 2-methyl-6-benzylidenecyclohexanones, conversion to the oxiranes by interaction with dimethylsulfonium methylide and reaction of the oxiranes with triazole or imidazole. The compounds obtained were tested for antifungal activity against five phytopathogenic fungi of different taxonomic classes. EC50 values were determined for all compounds. Structure–activity relationships are discussed in broad terms. Some of triazolymethyl-substituted cyclohexanols obtained are more active than triadimenol. © 1997 SCI. 相似文献
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Masatoshi Tamaru Naoshi Masuyama Masahiro Sato Fumiaki Takabe Jun Inoue Ryo Hanai 《Pest management science》1997,49(1):76-84
The previously evaluated prototype, methyl 6-acetyl-2-[(4,6-dimethoxypyrimidin-2-yl)oxy]benzoate, was modified by the introduction of an oximino group. Further extensive synthetic modifications were then made to the 6-alkyl moiety (R1), the ester moiety (R2), the alkoxyimino moiety (R3), the bridge-atom (X) and the 4,6-disubstituted-pyrimidine moiety (A, B, Z). Structure–activity relationships of the synthesized compounds were studied by examining their herbicidal activity against Barnyard grass (Echinochloa oryzicola) in paddy rice at various growth stages, including pre-emergence. The novel herbicide methyl 2-[(4,6-dimethoxypyrimidin-2-yl)oxy]-6-[1-(methoxyimino)ethyl]benzoate, (KIH-6127) was found to be the most effective compound. The commercial development of this compound is currently in progress. © 1997 SCI. 相似文献
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Christoph Lüthy Helmut Zondler Thomas Rapold Gottfried Seifert Bernhard Urwyler Thomas Heinis Hans Christian Steinrücken James Allen 《Pest management science》2001,57(3):205-224
A series of novel types of 7‐(4,6‐dimethoxypyrimidin‐2‐yl)oxy ‐ and ‐thio‐3‐methyl‐1 (3H)‐isobenzofuranones were discovered at Dr R Maag AG. From the thio‐isobenzofuranyl series, CGA 279 233—BSI‐proposed common name pyriftalid—was chosen for further development as a grass herbicide for use in rice. General synthetic approaches to these new phthalic acid‐derived compounds are given, with emphasis on the synthesis of pyriftalid and its physico‐chemical behaviour. © 2001 Society of Chemical Industry 相似文献
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A novel synthesis of methyl 6-acetylsalicylate as a key synthetic intermediate for methyl 2-[(4,6-dimethoxypyrimidin-2-yl)oxy]-6-[1-(methoxyimino)ethyl]benzoate (KIH-6127) was studied, and directed at 6-substituted pyrimidin-2-yl salicylate herbicides and their analogues. Three synthetic approaches were successful: a modification of the Sandmeyer reaction of 6-acetylanthranilate (Method A), a direct ring-opening reaction of 3-methylphthalide using potassium permangamate and magnesium nitrate (Method B), and a regioselective ortho-lithiation of the protected 3-hydroxyacetophenone (Method C). These methods were applicable for the synthesis of various 6-acyl salicylates. 相似文献
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为了进一步研究前期发现的除草先导化合物2-仲丁氨基-5-(2-氯吡啶-4-基)-1,3,4-噻二唑(BCPT)的结构-活性关系并提高其除草活性,设计并合成了一系列N-(1-甲氧羰基)乙基-N-[5-(2-氯吡啶-4-基)-1,3,4-噻二唑-2-基]酰胺类化合物。其苗后除草活性测定结果表明,所有化合物的活性都远低于BCPT本身。说明BCPT可能具有与传统酰胺类除草剂不同的作用机制。 相似文献
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Flury T Hall RG Karrer F Kienast H Leuenberger K Pascual A Rindlisbacher A Trah S Widmer HJ 《Pest management science》2006,62(3):236-241
Pro-pesticides of alpha-(2,6-dichloro-4-trifluoromethylphenylhydrazono)-4-nitrophenylacetonitrile have been prepared and tested against mite and insect pests. Variations in potency and spectrum were observed depending on the choice of cleavable pro-moiety. Cleavage of the pro-moiety was demonstrated in one case by measuring the rate of increase in the uncoupling activity using a mitochondrial preparation. Irradiation experiments have demonstrated a rapid isomerisation of the planar Z isomer to the E isomer, which is reversible. 相似文献
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A.T. Rodríguez R.M. Cárdenas M.G. Velázquez 《Pesticide biochemistry and physiology》2007,89(3):206-215
Seeds of rice (Oryza sativa L.) were treated with chitosan and hydrolyzed chitosan at 100, 500 and 1000 mg L−1. After 18 days of germination, spore suspension of Pyricularia grisea was applied. The enzyme activity of phenylalanine ammonia-lyase, β-1-3-glucanase, chitinase and chitosanase in leaves of rice seedlings was evaluated after 24, 72, 120 and 168 h of inoculation. Blast affected area (%) was evaluated 7 and 14 days after spraying spore suspension. Chitosan performance to elicit defense response induction was associated with the concentration and type of chitosan. The activity of most of the enzymes tested was induced in leaves of treated seeds with chitosan and hydrolyzed chitosan at 1000 and 500 mg L−1, respectively. The highest enzyme activities were observed with hydrolyzed chitosan after 72 h however, compared to chitosan, the activity was not maintained during the entire post-inoculation period. The highest control (0 = no lesions) of P. grisea in rice seedlings was observed at 1000 mg L−1 in both chitosan and hydrolyzed chitosan treated leaves. Symptoms of infection by P. grisea were evident after 14 days evaluation date, but according to the standard scale proposed by the International Rice Research Institute, these symptoms fell into the resistance category of blast diseases. 相似文献