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1.
通过N-烷基化反应合成了一系列新型含苯并咪唑的(S,S)-2,8-二氮杂双环[4.3.0]壬烷类衍生物,中间体化合物通过环化反应和酰化反应合成得到。所有新型化合物的结构均通过熔点测定、核磁共振氢谱和高分辨质谱确认。生物活性测试结果显示,目标化合物拥有中等的抗植物真菌活性,对东方粘虫Mythimna separata Walker和蚊幼虫Culex pipiens pallens具有中等到良好的杀虫活性。其中化合物6e和6f对油菜菌核Sclerotinia sclerotiorum、马铃薯晚疫Phytophthora infestans、小麦赤霉Fusarium graminearum等真菌具有良好的抗菌活性。化合物6e和6k在200mg/L下对东方粘虫的致死率为100%,化合物6h和6k在2mg/L下对蚊幼虫的致死率为75%。  相似文献   

2.
Fresh rhizomes of Zingiber officinale (ginger), when subjected to steam distillation, yielded ginger oil in which curcumene was found to be the major constituent. The thermally labile zingiberene‐rich fraction was obtained from its diethyl ether extract. Column chromatography of ginger oleoresin furnished a fraction from which [6]‐gingerol was obtained by preparative TLC. Naturally occurring [6]‐dehydroshogaol was synthesised following condensation of dehydrozingerone with hexanal, whereas zingerone and 3‐hydroxy‐1‐(4‐hydroxy‐3‐methoxyphenyl)butane were obtained by hydrogenation of dehydrozingerone with 10% Pd/C. The structures of the compounds were established by 1H NMR, 13C NMR and mass (EI‐MS and ES‐MS) spectral analysis. The test compounds exhibited moderate insect growth regulatory (IGR) and antifeedant activity against Spilosoma obliqua, and significant antifungal activity against Rhizoctonia solani. Among the various compounds, [6]‐dehydroshogaol exhibited maximum IGR activity (EC50 3.55 mg ml ?1) while dehydrozingerone imparted maximum antifungal activity (EC50 86.49 mg litre?1). © 2001 Society of Chemical Industry  相似文献   

3.
5-tert-Butyl-2-(4-ethynylphenyl)pyrimidine and the corresponding 2,5-disubstituted-4H-1,3-thiazine block the GABA-gated chloride channel at c.20and c.200 nm , respectively, measured as 50% inhibition of the binding of 1-(4-ethynylphenyl)-4-[3H]propyl-2,6,7-trioxabicyclo[2.2.2]octane (4′-ethynyl-4-n-[3H]propylbicycloorthobenzoate; [3H]EBOB) in house fly and mouse brain membranes, and they are also toxic to topically-treated flies with LD50 values of 6–27 μg g−1 alone and 2–6 μg g−1 with piperonyl butoxide (PB) as synergist. In the pyrimidine series, the general pattern of effectiveness of substituents in the 5-position is tert-butyl>isopropyl≈cyclohexyl≈cyclopropyl>methyl, phenyl and 3- and 4-fluorophenyl, and in the 2-position is 4-ethynylphenyl≪4-bromophenyl. These planar pyrimidines and nearly-planar 4H-1,3-thiazines with 2-ethynylphenyl or 2-bromophenyl and 5-tert-butyl or 5-isopropyl substituents are more effective than the corresponding 6H-1,3-thiazine, 6-oxo-1,3-thiazines and 4,6-dioxo-1,3-thiazine examined, but they are less active than the analogous conformationally flexible trans-1,3-dioxanes and -1,3-dithianes. The heterocyclic moiety confers a region of high electron density and positions the 2- and 5-substituents in a linear or parallel relationship for optimal affinity at the receptor. Two observations indicate that the new pyrimidines and thiazines probably act as chloride channel blockers. First, the poisoning signs are identical to those of EBOB in both mice and house flies. Second, each of the pyrimidines, thiazines and dioxanes falls on the same correlation line for inhibition of [3H]EBOB binding and toxicity to house flies (with PB) as that obtained earlier for EBOB analogs, dithianes and polychlorocycloalkanes, suggesting that they all act at the same or closely coupled binding sites in the GABA-gated chloride channel.  相似文献   

4.
2-z-Substituted benzylamino-4-substituted-amino-6-chloro-1,3, 5-triazines are herbicidal compounds showing leaf-burning and/or growth inhibition with concomitant greening and stunting. Effects of chiral 1,3,5-triazine compounds in a light-independent seedling root elongation test with Echinochloa crus-galli var. frumentacea Wight demonstrated an interaction between chirality and root growth inhibition. The test compounds inhibited root growth, and this inhibition was due to interference with a system or systems other than photosynthesis. 4-(R)-sec-butylamino-2-(α,α-dimethylbenzyl)amino-6-chloro-1,3, 5-triazine showed the highest inhibitory activity, and 4-methylamino-2-(R)-a-methylbenzylamino-6-chloro-1,3,5-triazine was second. The chiral requirement for a strong inhibition of root growth was the (R)-configuration, contrasting with the requirement for the (S)-configuration for an inhibition of photosystem II.  相似文献   

5.
BACKGROUND: The excellent fungicidal activity of [1,2,4]triazolo[1,5‐a]pyrimidines suggested the search for further analogues with improved properties. RESULTS: A series of novel trisubstituted pyrido[2,3‐b]pyrazines has been designed and prepared as 6,6‐biheterocyclic analogues of related 5,6‐bicyclic [1,2,4]triazolo[1,5‐a]pyrimidines. Their fungicidal activity was evaluated against the plant pathogens Puccinia recondita Rob. ex Desm. f. sp. tritici (Eriks.) CO Johnston (wheat brown rust), Mycosphaerella graminicola (Fuckel) Schroter (Septoria tritici Rob., leaf spot of wheat) and Magnaporthe grisea (Hebert) Barr (Pyricularia oryzae Cav., rice blast). Structure–activity relationship studies revealed the advantage of a fluoro substituent in position 6 and of a secondary amine in position 8. CONCLUSION: 8‐Amino‐7‐aryl‐6‐halogen‐substituted pyrido[2,3‐b]pyrazines have been prepared as 6,6‐biheterocyclic analogues of similarly substituted triazolopyrimidine fungicides. A concise four‐step synthesis route has been worked out to prepare these novel compounds from commercially available starting materials. [(R)‐(1,2‐Dimethylpropyl)]‐[6‐fluoro‐7‐(2,4,6‐trifluorophenyl)pyrido[2,3‐b]pyrazin‐8‐yl]amine showed excellent activity against three economically important phytopathogens. Copyright © 2009 Society of Chemical Industry  相似文献   

6.
以(E)-2-[2'-(bromo-methyl)phenyl]3-甲氧基丙烯酸甲酯和2(1H)-喹啉酮类化合物为原料,通过醚化等反应,合成了11个新型含2(1H)-喹啉酮结构的甲氧基丙烯酸酯类化合物,其结构经红外、电喷雾串联质谱(ESI-MS)和核磁共振氢谱确证。初步生物活性测试结果表明:在100 mg/L质量浓度下,部分目标化合物对烟草赤星病菌Alternaria alternata等6种病原菌具有一定的抑菌活性,其中5a对水稻稻瘟病菌Pyricularia grisea的抑菌率达100%。  相似文献   

7.
BACKGROUND: 1,3‐Dichloropropene (1,3‐D, CAS No. 542‐75‐6) is a broad‐spectrum soil fumigant used to control numerous species of soilborne plant‐parasitic nematodes. 1,3‐D consists of two isomers, (Z)‐ and (E)‐1,3‐D. There are a number of low‐level chlorinated compounds that could potentially be produced as a part of the 1,3‐D manufacturing process. 1,3‐D and its metabolites, as well as potentially related chlorinated compounds, represent potential groundwater contaminants. RESULTS: This study has investigated the hydrolytic stability, under biotic and abiotic conditions in the laboratory, of an extensive representative list of 1,3‐D and potentially related chlorinated compounds in order to predict their environmental fate. All of these compounds showed intrinsic hydrolytic instability under both abiotic and biotic test conditions. Furthermore, a monitoring programme was carried out. Twenty‐five wells were monitored in five Italian regions characterised by historical and existing use of 1,3‐D. The parent compound, its two major metabolites and potentially related chlorinated compounds were not detected in the well water at > 0.1 µg L?1 at any sampling location. CONCLUSION: The soil fumigant (E,Z)‐1,3‐D, its metabolites and potentially related chlorinated compounds constitute a low risk to groundwater. Copyright © 2011 Society of Chemical Industry  相似文献   

8.
Twelve ureas and thioureas with 1,3-diphenyl- and 1-phenyl-3-(2-pyridyl) were tested as potential herbicides in a simple screen against two species of algae Chlorella fusca and Anabaena variabilis. Several were shown to inhibit growth at 100 mg litre?1 but only 1-[2,4-bis(azidosulphonyl)phenyl]-3-(2-pyridyl)urea and 1,3-bis(4-isopropyl- idenehydrazinosulphonylphenyl)thiourea showed any activity at 1 mg litre?1. This compares with the well-established urea herbicide diuron which, in identical tests, gives similar inhibition of growth at concentrations as low as 0.01 mg litre?1.  相似文献   

9.
N-Arylcarbamoylpyrazolines with various substituents at the para position of the carbamoyl benzene ring inhibited ATP-dependent Ca2+-uptake in synaptosomes prepared from the rat brain. The activity of these compounds was evaluated as log(1/I50), the reciprocal logarithm of half inhibitory concentration, I50 (m ), from the concentration–response curve for the inhibition of Ca2+-uptake. Among the compounds tested, methyl 3-(4-chlorophenyl)-4-methyl-1-[N-(4-trifluoromethylphenyl)carbamoyl]-2-pyrazoline-4-carboxylate was the most potent, the I50 value of which as 9·12×10−7 m . Variations in the activity in terms of log(1/I50) were quantitatively analysed using a substituent parameter, showing that the higher the electron-withdrawing effect of the substituent, the higher was the activity. The substituent effects were similar to those on insecticidal activity against the Americal cockroach. The higher the inhibitory activity against Ca2+ uptake, the higher seemed to be the insecticidal activity. Methyl(4S) - 3 - (4 - chlorophenyl) - 4 - methyl - 1 - [N - (4 - chlorophenyl)carbamoyl] - 2 - pyrazoline -4-carboxylate had higher inhibitory activity against Ca2+-uptake and higher in-secticidal activity than the R-isomer, but the difference was greater in theCa2+-uptake system.  相似文献   

10.
Four green-odour compounds—trans-2-hexenal, cis-3-hexenol, n-hexanal, and cis-3-hexenal—were applied (0.85 μg ml−1 as vapour) to rice plants in laboratory conditions to observe their biological activity against the phytopathogenic fungus Maganporthe oryzae, which causes rice blast disease worldwide. Two compounds, trans-2-hexenal and cis-3-hexenal, showed remarkable disease suppression efficacy (99.7% and 100% suppression, respectively), while n-hexanal had moderate (86.5%) and cis-3-hexenol had weak (20.8%) disease-suppressing effects. Pre-application and post-application of trans-2-hexenal or cis-3-hexenal had slight effects on blast incidence, suggesting that these compounds had direct effects to suppress M. oryzae infection. In fact, trans-2-hexenal and cis-3-hexenal exhibited a growth suppression effect on M. oryzae. Interestingly, these two compounds inhibited appressorium formation at lower concentrations than the growth suppression. Studies on the hypersensitive response (HR)-like reaction and plant β-1,3-glucanase activity in rice plant confirmed that induced resistance was not the major factor involved in the disease suppression mechanism. Results of this study conclusively showed that trans-2-hexenal and cis-3-hexenal possess potent inhibitory activities against the growth and the appressorium formation of M. oryzae and could be used as antifungal agents to significantly reduce M. oryzae infections in rice.  相似文献   

11.
A series of 14 new 3-[4(3H)-quinazolinone-2-(yl)thiomethyl]-1,2,4-triazoles were prepared and characterized by elemental analyses, IR, [1H] NMR and mass spectral data. Four of the compounds showed insecticidal activity equivalent to that of malathion against the adult stage of the blow fly (Chrysomyia albiceps). However, their activity against the larval stages of this insect species was considerably weaker.  相似文献   

12.
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   

13.
A series of 2-amino-5-substituted pyridine derivatives was synthesized and their molluscicidal activity against white garden, Theba pisana (Müller), and brown garden, Helix aspersa (Müller), snails was investigated by two methods of application. Some of these compounds showed strong activity under laboratory conditions against the two types of snail. T pisana was more sensitive to the tested compounds than H aspersa. The most effective compounds were 2-amino-5-(benzotriazole-1-ylmethyl)-3-methylpyridine, 2-amino-5-[1-(benzotriazole-1-yl)nonyl]-3-methylpyridine and 2-[(1,2,4-triazole-1-ylmethyl)amino]-3-methylpyridine which exhibited high molluscicidal activity. The toxicity results are discussed in relation to the chemical structures. © 1999 Society of Chemical Industry  相似文献   

14.
The antifungal activities in vitro of 43 methoxy- and hydroxy-substituted aryl-benzofurans, phenylbenzo[b]thiophenes and phenylindoles were compared with those of the unsubstituted compounds. Monohydroxy derivatives were usually the most fungitoxic against Alternaria brassicicola, Botrytis cinerea, Septoria nodorum, Cladosporium cucumerinnum, Fusarium culmorum and Uromyces fahae but the precise effect of substitution upon activity varied with the nature of the parent aryl-hetocyclic compound, with the position in the molecule, and with the presence of other substituents. Fangitoxicity did not correlate significantly with the partitioning properties of the molecuie as measured by reversed-phase thin-layer chromatography.  相似文献   

15.
BACKGROUND: Phthalic acid diamide derivatives are among the most important classes of synthetic insecticides. In this study, a 3,3‐dichloro‐2‐propenyloxy group, the essential active group of pyridalyl derivatives, was incorporated into phthalic acid diamide derivatives with the aim of combining the active groups to generate more potent insecticides. RESULTS: Thirty‐one new phthalic acid diamides were obtained, and these were characterised by 1H and 13C NMR. The structure of N2‐[1,1‐dimethyl‐2‐(methoxy)ethyl]‐3‐iodo‐N1‐[4‐(3,3‐dichloro‐2‐propenyloxy)‐3‐(trifluoromethyl)phenyl]‐1,2‐benzenedicarboxamide was determined by X‐ray diffraction crystallography. The insecticidal activities of the compounds against Plutella xylostella were evaluated. The title compounds exhibited excellent larvicidal activities against P. xylostella. Structure‐activity relationships revealed that varying the combination of aliphatic amide and aromatic amide moieties, or the nature and position of substituent Y on the aniline ring, could aid the design of structures with superior performance. CONCLUSION: A series of novel phthalic acid diamides containing a 3,3‐dichloro‐2‐propenyloxy group at the 4‐position of the aniline ring were designed and synthesised. Structure‐activity relationships with the parent structure provided information that could direct further investigation on structure modification. Copyright © 2012 Society of Chemical Industry  相似文献   

16.
The metabolism of cis- and trans-1,3-dichloropropene (1,3-D) was studied in soybean plants grown in soil treated 24 days prior to planting with [U-14C]E- and Z-1,3-dichloropropene at 380 liters ha?1. Isolation and identification of the 14C residue from soybean plants at 84 days (forage) and 176 days (mature) after application showed that no 1,3-dichloropropene or its putative metabolites, 3-chloroallyl alcohol and 3-chloroacrylic acid, could be detected in any of the tissues. The components of the 14C residue included major plant constituents (i.e. fatty acids, protein, pigments, organic acids, sucrose and other carbohydrates, and lignin).  相似文献   

17.
设计合成了一系列结构新颖的嘧啶联吡唑甲酰胺类化合物5a~5o,其结构均经过1H NM R和MS分析确证。初步生物活性测试结果表明:在有效成分150 g/hm2剂量下苗后茎叶喷雾处理时,化合物(R)-N-[1-(4-氯苯基)乙基]-3-二氟甲基-1-(4,6-二甲氧基嘧啶-2-基)-1H-吡唑-4-甲酰胺(5c)、N-[1-(4-氯苯基)乙基]-1-(4,6-二甲氧基嘧啶-2-基)-N-甲基-3-三氟甲基-1H-吡唑-4-甲酰胺(5i)和N-[1-(4-氯苯基)乙基]-1-(4,6-二甲氧基嘧啶-2-基)-3-三氟甲基-1H-吡唑-4-甲酰胺(5k)对繁缕Stellaria media的抑制率高达90%以上;而同样剂量下苗前土壤喷雾处理时,化合物N-[1-(4-氯苯基)乙基]-3-二氟甲基-1-(4,6-二甲氧基嘧啶-2-基)-1H-吡唑-4-甲酰胺(5b)和5c对繁缕的抑制率达100%。该类结构化合物有望作为除草先导化合物进行开发。  相似文献   

18.
Nine diethyl chloroacetylanilidomethylphosphonates and ten diethyl α-(chloroacetylanilido)benzylphosphonates were prepared by N-chloroacetylation of the corresponding diethyl anilinomethyl- and anilinobenzylphosphonates. These were tested for antifungal activity against six phytopathogenic fungi. Most of the compounds showed moderate protective properties. No significant difference in activity was observed for compounds with an extra aryl ring substituent on the methylene group of the backbone. Compounds with electron-withdrawing substituents, especially chlorine, on the aniline site (R1) showed higher fungicidal activity than the other compounds with electron-donating groups as substituents.  相似文献   

19.
Proteins extracted from suspension-cultured soybean (Glycine max (L.) Merr. Corsoy 79) cells contained O- and N-glucosyltransferases (GTs; EC 2.4.1) that catalyzed glucosylation of several xenobiotic compounds including (a) the hydroxylated herbicide metabolites 6-hydroxybentazone (B-6-OH), 8-hydroxybentazone and 5-hydroxydiclofop (b) the herbicide chloramben and (c) the environmental contaminants 2,4-dichlorophenol and 3,4-dichloroaniline. The O-GT that catalyzes B-6-OH glucosylation, UDP-glucose: B-6-OH glucosyltransferase (B6GT), was chosen for further study. A rapid and sensitive B6GT assay was developed that uses ethyl acetate extraction to separate the product 6-O-[14C]glucosylbentazone from the glucose donor uridine[5′]diphospho-[1]-α-D -[U-14C]glucose. B6GT, recovered in the soluble protein fraction, was extracted in consistently high amounts from Corsoy 79 cells cultured for one to seven days. 2-Mercaptoethanol in the extraction buffer increased B6GT activity as did sodium, potassium, calcium, magnesium or manganese(II) chlorides in the assay buffer. B6GT activity in an ammonium sulfate fraction (30–50% saturation pellet) displayed two pH optima, one at pH 5.5 and another at pH 10 to 11. Apparent Km values for UDP-glucose and B-6-OH in the ammonium sulfate fraction were 90 and 4.5μM, respectively. Thus, we have partially characterized glucosylation of B-6-OH, one example of the several xenobiotic GT activities present in Corsoy 79 soybean.  相似文献   

20.
7-Hydroxy-5-oxo-5H-thieno[3,2-b]pyran-6-carboxanilides and -6-thio-carboxanilides represent a novel series of anthelmintic compounds, with broad-spectrum activity against important parasitic nematodes in sheep and dogs. In particular, an improved efficacy against Trichostrongylus colubriformis in sheep over the related 3-carbamoyl-4-hydroxycoumarins has been noted. New synthetic routes to the key intermediate, 7-hydroxythieno[3,2-b]pyran-5-one, have been developed.  相似文献   

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