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1.
The systemic activity of simeconazole (RS-2-(4-fluorophenyl)-1-(1H-1,2,4-triazol-1-yl)-3-trimethylsilylpropan-2-ol) and a number of its derivatives in plants has been investigated to establish which portion of the structure of the molecule contributes to this outstanding activity. The results revealed that the hydroxyl group of the simeconazole moiety is essential for vapour-phase activity and translocation from roots of the compound. They showed that the presence of a fluorine atom in the structure was not indispensable for vapour-phase activity or translocation from roots, although the fluorine atom contributed to these systemic movements. In addition, it was found that the fungicidal activity of simeconazole against Rhizoctonia solani Kühn and Blumeria graminis DC fsp hordei Marchal is potentiated by the fluorine atom, since the activity of a compound which lacked fluorine in the 4-position of the phenyl ring was inferior to that of simeconazole. A compound in which the silicon atom of simeconazole was replaced by a carbon atom showed lower antifungal activity than simeconazole, while phytotoxicity was caused in rice plants by soil drench of the compound. Therefore, the silicon atom of simeconazole may contribute to its selectivity between fungi and plants. 相似文献
2.
为了寻找高活性的三唑类苯基氨基甲酸酯衍生物,以 1,2,4-三氮唑、2-氯-2,4-二氟苯乙酮为原料,采用活性亚结构拼接的策略,设计并合成了18个未见文献报道的N-取代苯基-1-(2,4-二氟苯基)-2-(1H-1,2,4-三唑-1-基)乙基氨基甲酸酯衍生物 6a ~ 6r 。其结构均通过 1H NMR、13C NMR和高分辨质谱（HRMS）的确证。抑菌活性测定结果显示:在100 μmol/L下,化合物 6m 对6种供试真菌具有良好的抑制作用,抑制率均达到50%以上。化合物 6p 对油菜菌核病菌Sclerotinia sclerotiorum的EC50值为7.1 μmol/L,抑菌活性高于对照药剂烯唑醇（EC50值9.1 μmol/L）。杀螨活性测定结果显示,在150 μmol/L时,化合物 6h 、 6k 和 6o 在48 h时对朱砂叶螨Tetranychus cinnabarinus的致死率分别为67.7%、74.9%和57.5%,杀螨活性低于对照药剂阿维菌素B1a(致死率100%)。本研究所合成的化合物 6o 兼具一定杀菌和杀螨活性,可为新型三唑类杀菌杀螨化合物的设计与研究提供参考。 相似文献
3.
为了发现具有生物活性的新化合物,以溴代吡咯腈为先导化合物,通过亲核取代等反应合成了一系列新型2-(溴代吡咯腈-1-基)乙酸衍生物(5a～5m, 6a～6o),其结构均经核磁共振氢谱(1H NMR)、碳谱(13C NMR)和高分辨质谱(HRMS)确证。杀菌活性测定结果显示：化合物2、3和5m对水稻稻瘟病菌Magnaporthe oryzae均表现出良好的杀菌活性,其EC50值分别为0.0532、0.0470和0.0174 mmol/L,优于对照药剂咯菌腈(0.0914 mmol/L),但不及对照药剂嘧菌酯(0.0001 mmol/L);化合物5m表现出一定的杀菌广谱性,其对水稻纹枯病菌Rhizoctonia solani和小麦根腐病菌Bipolaris sorokiniana的EC50值分别为0.0218和0.0420 mmol/L,但均不及对照药剂咯菌腈(EC50值分别为0.0002和0.0010 mmol/L)。杀虫、杀螨活性测定结果显示,在0.2 mmol/L浓度下,目标化... 相似文献
4.
防护林沙拐枣人工平茬更新复壮效果分析 总被引：2，自引：0，他引：2
为保证古尔班通古特沙漠渠道防护林防护效益的持续性，对林中沙拐枣进行3种不同平茬数量规格的试验，即平茬沙拐枣的数量分别为样地中沙拐枣总量的50%、67%和78%，结果表明：① 人工平茬处理在一定程度上促进了沙拐枣根系对土壤水分的吸收。② 人工平茬后， 沙拐枣植株生长迅速，生长活力旺盛，平茬当年已经起到良好的防风固沙效果；③平茬增大了沙拐枣同化枝的有效表面积，生物量增加，提高了沙拐枣的生产力。3种平茬规格处理下，沙拐枣更新复壮都取得了显著的效果，在78%平茬数量规格下沙拐枣生长状况最好，平茬效果最佳，防护效益随着后期生长将持续增大。 相似文献
5.
含氟2-氧代环己基磺酰胺的合成及杀菌活性 总被引：3，自引：3，他引：0
以环己酮为原料,经磺酰化、碱化后得到2-氧代环己基磺酸钾盐,再经生成酰氯后与胺反应得到9个新的标题化合物,其结构经1H NMR、13C NMR和元素分析确证。初步的生物测定结果表明,部分化合物具有一定的杀菌活性,其中 3e 对棉花立枯病菌Rhizoctonia solani和黄瓜灰霉病菌Botrytis cinerea、 3h和3i 对黄瓜灰霉病菌和油菜菌核病菌Sclerotinia sclerotiorum有较好的活性,50 μ g/mL下的抑制率均在90％以上。 相似文献
6.
Rabea EI Badawy ME Rogge TM Stevens CV Höfte M Steurbaut W Smagghe G 《Pest management science》2005,61(10):951-960
Chitosan, the N-deacetylated derivative of chitin, is a potential biopolysaccharide owing to its specific structure and properties. In this paper, we report on the synthesis of 24 new chitosan derivatives, N-alkyl chitosans (NAC) and N-benzyl chitosans (NBC), that are soluble in dilute aqueous acetic acid. The different derivatives were synthesized by reductive amination and analyzed by 1H NMR spectroscopy. A high degree of substitution (DS) was obtained with N-(butyl)chitosan (DS 0.36) at a 1:1 mole ratio for NAC derivatives and N-(2,4-dichlorobenzyl)chitosan (DS 0.52) for NBC derivatives. Their insecticidal and fungicidal activities were tested against larvae of the cotton leafworm Spodoptera littoralis (Boisduval) (Lepidoptera: Noctuidae), the grey mould Botrytis cinerea Pers (Leotiales: Sclerotiniaceae) and the rice leaf blast Pyricularia grisea Cavara (Teleomorph: Magnaporthe grisea (Hebert) Barr). The oral feeding bioassay indicated that all the derivatives had significant insecticidal activity at 5 g kg(-1) in artificial diet. The most active was N-(2-chloro-6-fluorobenzyl)chitosan, which caused 100% mortality at 0.625 g kg(-1), with an estimated LC50 of 0.32 g kg(-1). Treated larvae ceased feeding after 2-3 days; the mechanism of action remains unknown. In a radial hyphal growth bioassay with both plant pathogens, all derivatives showed a higher fungicidal action than chitosan. N-Dodecylchitosan, N-(p-isopropylbenzyl)chitosan and N-(2,6-dichlorobenzyl)chitosan were the most active against B cinerea, with EC50 values of 0.57, 0.57 and 0.52 g litre(-1), respectively. Against P grisea, N-(m-nitrobenzyl)chitosan was the most active, with 77% inhibition at 5 g litre(-1). The effect of different substitutions is discussed in relation to insecticidal and fungicidal activity. 相似文献
7.
Li XH Ji MS Qi ZQ Li XW Shen YX Gu ZM Zhang Y Wei SH Wang YZ Wang DQ 《Pest management science》2011,67(8):986-992
BACKGROUND: With the objective of exploring the fungicidal activity of 2‐oxocyclohexylsulfonamides (2), a series of novel 2‐amino‐6‐oxocyclohexenylsulfonamides (6 to 23) were synthesised, and their fungicidal activities against Botrytis cinerea Pers. were evaluated in vitro and in vivo. RESULTS: The compounds were characterised by IR, 1H NMR and elemental analysis. Bioassay results of mycelial growth showed that compounds 6 to 23 had a moderate antifungal activity against B. cinerea. N‐(2‐methylphenyl)‐2‐(2‐methylphenylamino)‐4,4‐dimethyl‐6‐oxocyclohexenylsulfonamide (13) and N‐(2‐chlorophenyl)‐2‐(2‐chlorophenylamino)‐6‐oxocyclohexenylsulfonamide (21) showed best antifungal activities, with EC50 values of 8.05 and 10.56 µg mL?1 respectively. Commercial fungicide procymidone provided an EC50 value of 0.63 µg mL?1. The conidial germination assay showed that most of compounds 6 to 23 possessed excellent inhibition of spore germination and germ‐tube elongation of conidia of B. cinerea. For in vivo control of B. cinerea colonising cucumber leaves, the compound N‐cyclohexyl‐2‐(cyclohexylamino)‐4,4‐dimethyl‐6‐oxocyclohexenylsulfonamide (19) showed a better control effect than the commercial fungicide procymidone. CONCLUSION: The present work demonstrated that 2‐amino‐6‐oxocyclohexenylsulfonamides can be used as possible new lead compounds for further developing novel fungicides against B. cinerea. Copyright © 2011 Society of Chemical Industry 相似文献
8.
为了发现农药活性的新化合物,以溴代吡咯腈为原料,通过亲核取代、肼解和成环等反应,设计合成了一系列N-((5-烷硫基-1,3,4-噁二唑)-2-基)甲基溴代吡咯腈目标化合物( 5a ~ 5t ),所有化合物的结构均得到核磁共振氢谱和高分辨质谱确证。杀菌活性测定结果显示:在浓度为0.20 mmol/L时,大部分目标化合物具有一定的抑菌活性,其中化合物 5h 对水稻稻瘟病菌Magnaporthe oryzae的抑制率为60.07%,优于对照药剂咯菌腈(58.21%)。杀虫与杀螨活性测定结果显示:在浓度为0.20 mmol/L时,大部分目标化合物对斜纹夜蛾Spodoptera litura和朱砂叶螨Tetranychus cinnabarinus雌成螨具有一定的杀虫和杀螨活性,但均低于对照药剂虫螨腈(100%)。杀线虫生物测定结果显示:在浓度为0.20 mmol/L时,大部分目标化合物表现出优异的杀线虫活性,其中化合物 5k 、 5r 和 5s 对秀丽隐杆线虫Caenorhabditis elegans的LC50值分别为0.0918、0.0733和0.0810 mmol/L,优于对照药剂噻唑膦(0.2798 mmol/L)。本研究所合成的目标化合物具有一定的杀菌、杀虫、杀螨和杀线虫活性,可为溴代吡咯腈衍生物的设计和合成提供参考。 相似文献
9.
BACKGROUND: Systemicity is an important attribute of fungicides that is difficult to measure in early‐stage screening without labeling the compound with a radioisotope. A method of measuring translocation that does not require potent fungicidal activity or a radiolabel would guide identification of compounds with desirable attributes. RESULTS: The authors developed an analytical technique that mimics field application, using LC‐MS/MS to screen compounds for translocation in wheat leaves. The method sorted commercial and experimental fungicides appropriately into systemic and non‐systemic categories. A model using LC‐MS/MS data was equivalent to a lipophilicity model and superior to a water solubility model at predicting compound systemicity. CONCLUSION: Early‐stage compounds can be screened for systemicity on whole plants using LC‐MS/MS. Copyright © 2008 Society of Chemical Industry 相似文献
10.
This study describes the chemical synthesis and intrinsic fungicidal activity of ethaboxam [(RS)-N-(alpha-cyano-2-thenyl)-4-ethyl-2-(ethylamino)-1,3-thiazole-5-carboxamide], a new Oomycetes fungicide. In in vitro tests, ethaboxam showed inhibitory activity against isolates of Phytophthora and some Pythium spp, with MIC values ranging from 0.1 to 0.5 mg litre(-1) for nine isolates of Phytophthora infestans (Montagne) de Bary and from 1.0 to 5.0 mg litre(-1) for eight isolates of Phytophthora capsici Leonian. In tests to determine time and concentration for complete inactivation of each pathogen (five isolates of P infestans and five isolates of P capsici), ethaboxam inactivated all isolates of P infestans within 48h at 10 mg litre(-1) and those of P capsici within 96 h at 10 mg litre(-1). Ethaboxam effectively suppressed development of tomato late blight caused by P infestans and pepper Phytophthora blight caused by P capsici in the studies conducted to determine its preventive, curative, persistent and systemic activity. These results show that ethaboxam has desirable fungicidal characteristics as an Oomycetes fungicide. 相似文献
11.
Paul H. Smith Keith Chamberlain Jane M. Sugars Richard H. Bromilow 《Pest management science》1995,44(3):219-224
More than 20 N-(2-cyano-2-methoximinoacetyl)amino acids and derivatives were synthesised and tested for antifungal activity against grape downy mildew, caused by Plasmopara viticola (de Bary) Berl. & de Toni, and rape downy mildew, Peronospora parasitica Fr. Two of the compounds containing a free carboxylic acid group, a moiety which has been shown to confer phloem mobility on compounds, showed high activity, especially against P. parasitica, in protectant tests. These results indicate that there is no incompatibility between the acid function and fungicidal activity. A number of the esters showed activity comparable with that of cymoxanil in the protectant tests, and the tert-butyl esters of the methionine derivative and its sulfone were more than ten times as active as the commercial compound. 相似文献
12.
A series of novel oxime ether β-methoxyacrylates have shown good fungicidal activity against a number of fungal pathogens. These were designed by introducing a one- or two-atom spacer group adjacent to the oxime ether group. Best fungicidal activity was obtained when an amino spacer group was used. ©1999 Society of Chemical Industry 相似文献
13.
2-[4-(对氟苯基)噻唑-2-基]-3-羟基-3-烃氧基丙烯腈的合成及杀菌活性 总被引：2，自引：2，他引：0
为了寻找生物活性良好的噻唑基丙烯腈类化合物,利用2-氰甲基-4-(对氟苯基)噻唑( 3 )与取代氯甲酸酯( 4 )在碱存在下反应,合成了15个未见文献报道的2- -3-羟基-3-烃氧基丙烯腈化合物( 5 ),其结构经核磁共振氢谱、质谱和元素分析表征。初步杀菌活性测试结果表明:所有化合物在试验浓度下均具有一定的抑菌活性,尤其对炭疽病菌Colletotrichum gossypii表现出较好的抑制活性,在质量浓度25 mg/L下,所有化合物的抑制率均在50%以上,其中化合物 5a、5e、5g、5k、5n和5o 的抑制率在80%以上。 相似文献
14.
对广泛存在于链霉菌和铜绿假单胞菌中的一种天然活性物质——申嗪霉素进行了结构修饰,合成了一系列高活性的含1,3,4-噻(噁)二唑的申嗪霉素衍生物 I 1 ~ I 28 。杀菌活性测定结果表明:所有目标化合物对禾谷镰刀菌具有较好的杀菌活性,均明显优于母体申嗪霉素。离体杀菌活性测定结果显示,化合物 I 8 (EC50 = 33.25 μg/mL)和化合物 I 22 (EC50 = 46.52 μg/mL)对禾谷镰刀菌的杀菌活性是申嗪霉素 (EC50 = 128.54 μg/mL)的3~4倍。活体杀菌活性显示,在500 μg/mL质量浓度下,化合物 I 8 (58.69%)和化合物 I 22 (55.37%)对禾谷镰刀菌的抑制率是申嗪霉素 (25.14%) 的两倍。构效关系分析结果表明,在苯环上引入吸电子基团对化合物的活性不利;而引入给电子基团则有利于提高其杀菌活性。同时,同一取代基在苯环上的取代位置依据活性的高低排列顺序为:邻位>对位>间位。这些结果可用于指导该类化合物的进一步结构改造。 相似文献
15.
调控基因gacA在荧光假单胞菌2P24防治土传病害中的作用 总被引：5，自引：0，他引：5
Pseudomonas fluorescens 2P24分离自山东小麦全蚀病自然衰退土壤,该菌株能产生抗生素2,4-二乙酰基藤黄酚(2,4-diacetylphloroglucinol,2,4-DAPG)、氢氰酸,嗜铁素和蛋白酶,且抑菌谱广,可防治多种作物土传病害。本研究应用Tn5转座突变技术,获得1株产嗜铁素过量,同时不产生2,4-DAPG、HCN、蛋白酶、不能形成生物膜(biofilm)的突变菌株PM3390,其表现型与调控基因gacA的突变体表型相似。通过PCR介导的文库筛选方法,从2P24基因组文库中获得2个含有gacA基因的阳性克隆,进一步亚克隆,得到只含有完整gacA开放阅读框的1.2 kb片段,互补实验表明其能恢复突变菌株的多种缺失表型。生测结果表明,gacA-突变菌株与野生型2P24相比,对不同土传病害的生防效果均显著降低。以上结果证实gacA在2P24中具有整体水平的调控功能,并在2P24防治土传病害中起到重要的作用。 相似文献
16.
链格孢菌Alternaria alternata引起的棉花轮纹斑病,是导致棉花早衰发生的主要成因之一,严重危害棉花生产。香豆素合成途径作为合成植保素的一条代谢支路,其产物能够抑制病原菌,增强植物的抗病性。为了揭示该途径在棉花抗链格孢菌中的作用,本文利用棉花皱缩病毒介导的基因沉默技术,通过对棉花香豆素合成途径中编码关键酶基因的沉默抑制,来解析其在棉花抗链格孢菌中的作用,所选择的基因有编码苯丙氨酸解氨酶(PAL)的基因Ghpal、肉桂-4-羟化酶(C4H)基因Ghc4h和4香豆酸-辅酶-A(4CL)的基因Gh4cl。结果显示,Ghpal、Ghc4h和Gh4cl基因受链格孢菌诱导转录,表明这些基因可能参与了棉花对链格孢菌的抗性反应。Ghpal、Ghc4h和Gh4cl基因分别被沉默后,结果显示各基因沉默植株对链格孢菌的抗性下降,表现为接种链格孢菌后,基因沉默植株的病情指数分别为43.36、38.27和44.78,显著高于野生型和VIGS空载体对照植株。这表明,Ghpal、Ghc4h和Gh4cl参与了棉花对链格孢菌的抗性反应。此外,离体条件下给Ghpal、Ghc4h和Gh4cl基因沉默植株叶片饲喂外源香豆素,结果发现基因沉默植株对链格孢菌的抗性得到恢复。这一结果进一步表明香豆素合成途径在棉花抗链格孢菌中起着重要作用。 相似文献
17.
18.
Anna Arnoldi Eliseo Betto Lucia Ceresa Gandolfina Farina Attilio Formigoni Remo Galli Leonardo Scaglioni 《Pest management science》1983,14(6):576-586
A series of 1-(3-pyridyl)-1-substituted-but-3-yn-1-ols and some related compounds were synthesised and tested for antifungal activity against eight phytopathogenic fungi of different taxonomic classes. High activity was shown in particular against Sphaerotheca fuliginea on Cucumis sativus. The compounds containing aromatic substituents gave the best results, not only in protectant but also in systemic and eradicant tests. The quantitative structure-activity relationship suggests that steric effects play an important role in determining fungicidal activity. 相似文献
19.
为了发现更高杀菌活性的螺环丁烯内酯类化合物并分析该类化合物的构效关系，设计并合成了一系列未见文献报道的含咪唑并噻唑、咪唑并噻嗪和咪唑并噻嗪酮等稠杂环结构的螺环丁烯内酯类化合物，其结构通过核磁共振氢谱 (1H NMR)、碳谱 (13C NMR)及高分辨质谱 (HRMS)确证。离体杀菌活性测试结果表明，化合物 5f 和 6f 对油菜菌核病菌的EC50值分别为33.2和29.8 mg/L，优于对照药剂咪唑菌酮(46.8 mg/L)，化合物 7b 和 7e 对辣椒疫霉的EC50值分别为45.8和43.5 mg/L，优于咪唑菌酮(50.7 mg/L)，与先导化合物相比，其杀菌活性高于2-甲硫基衍生物，低于2-芳氨基衍生物，表明稠杂环的引入可以提高化合物的杀菌活性，而结构中的NH片段对杀菌活性具有关键作用。 相似文献
20.
N-(5-芳基-1,3,4-嗯二唑-2-基)-N''-α-萘乙酰基硫脲的合成及杀菌活性 总被引：3，自引：1，他引：3
从α-萘乙酸出发,合成酰基异硫氰酸酯,然后与2-氨基-5-芳基-1,3,4-嗯二唑反应合成了8个新的酰基硫脲类化合物 Ⅱa~Ⅱh 。所有化合物的结构均经元素分析、红外光谱、核磁共振氢谱和质谱确认。同时对6种病原菌进行了生物活性测试,结果发现,在50 mg/L下,所有目标化合物对黄瓜灰霉病菌Botrytis cinereapers的抑制效果较好,除 Ⅱa 外,其他化合物抑制率都达到80%以上。 相似文献