bluuebunny/crossref_metadata_2025_split huggingface dataset:
Inhibition of pheromone action in Sesamia nonagrioides by Haloacetate analogues
Authors: Riba Magi , Eizaguirre Matilde , Sans Albert , Quero Carmen , Guerrero Angel 
Published: November 2006

AbstractThe electrophysiological activity of some halogenated analogues of the major component of the sex pheromone of the corn stalk borer Sesamia nonagrioides Lef. (1) is presented. The analogues comprise a series of fluoro‐, chloro‐ and bromoacetate analogues4–10 as well as trifluoromethyl ketone 11. The fluoro derivatives 4–6 displayed remarkable electro‐antennogram (EAG) intrinsic activities in comparison with the parent acetate 1, while the remaining analogues elicited significantly lower response. The compounds have also been tested as inhibitors of the sex pheromone perception in EAG and in the field. In the laboratory. fluoro analogues 4–6 were better inhibitors than chloro derivatives 7–9, which in turn behaved similarly to the bromoacetate 10. Trifluoromethyl ketone 11, however, was a poor inhibitor of the pheromone action. In the field, baits of mixtures of compounds 5–11 with the corn stalk borer pheromone in 10:1 ratio inhibited the concomitant attraction of the clover cutworm moth Scotogramma irifolii Rott., while the difluoro analogue 5, trichloroacetate 9 and trifluoromethyl ketone 11 also diminished the number of catches of the armyworm Mythimna unipuncta Haw. The monofluoroacetate 4. trifluoro analogue 6 and bromo derivative 10 significantly disrupted the pheromone action of the corn borer, whereas trifluoromethyl ketone 11 synergistically increased the number of males attracted to the pheromone trap alone. Addition of 11 to baits containing the corn borer pheromone caught S. nonagrioides selectively with regard to the other habitat‐sharing species M. unipuncta and S. trifolii.
HPLC separation and subsequent detection of aromatic heptaene polyenes in peat after treatment with Streptomyces griseoviridis
Authors: Raatikainen Olavi J. , Päivinen Tuulikki H. , Tahvonen Risto T. 
Published: November 2006

AbstractAromatic heptaene polyenes (AHPs), the largest group of antifungal polyene antibiotics, were detected in steam‐sterilized Sphagnum peat after treatment with a new biofungicide containing fermenter‐cultivated Streptomyces griseoviridis Anderson K61, a bacterium capable of producing AHPs in vitro. Three concentrations (0.05 g litre−1, 0‐2 g litre−1 and 2.0 g litre−1) of the biofungicide were used and compared to untreated controls. The substrates were incubated for seven weeks under greenhouse conditions, with and without cucumber seedlings, and samples were analysed for heptaene polyenes by HPLC using a photodiode array detector. Changes in AHP concentrations indicated that the fermenter‐cultivated mycelium was a partial source of extractable heptaenes in peat. The identification of p‐aminoacetophenone (PAAP) by HPLC‐MS in peat hydrolysates verified the presence of AHPs.
Modeling root absorption and translocation of 5‐substituted analogs of the imidazolinone herbicide, imazapyr
Authors: Little Desiree L. , Ladner David W. , Shaner Dale L. , Ilnicki Richard D. 
Published: November 2006

AbstractQuantitative structure‐activity relationships (QSAR) were developed between the physicochemical parameters of the 5‐substituent of a series of analogs of the imidazolinone herbicide, imazapyr, and root absorption, translocation, inhibition of acetohydroxyacid synthase (AHAS), and herbicidal activity of the analogs. An optimum substituent lipophilicity (π = 1.85–2–3) for root absorption was identified for corn (Zea mays L.) and sunflower (Helianthus annuus L.). Translocation from roots to shoots was greatest for those analogs having either highly nonpolar or highly polar 5‐substituents, indicating that both symplastic and apopiastic mechanisms may be functioning. In addition, translocation from roots was positively correlated with electron‐withdrawing parameters of the 5‐substituent, and a possible mechanism governing this relationship is discussed. Modeling in vitro AHAS inhibition was not successful, but models were developed for herbicidal activity as measured in an Arabidopsis thaliana (L.) Hevnh. bioassay. The whole‐plant models described an optimum substituent lipophilicity (π = 0 71) which probably reflected the influence of this parameter on the component processes of absorption and translocation. Whole‐plant activity was also greater for analogs having electron‐donating 5‐substituents; this result suggests that electron donation may be important for metabolism, or more likely, for AHAS inhibition.
The toxicity of the rodenticide flocoumafen to barn owls and its elimination via pellets
Authors: Newton Ian , Wyllie Ian , Gray Alan , Eadsforth Charles V. 
Published: November 2006

AbstractIn a Barn Owl feeding study, five birds were fed with flocoumafen‐dosed mice for consecutive periods of one, three and six days. Following each of these periods the owls were allowed to recover on undosed diet. Four of the birds survived all the treatments, but the fifth bird, which had been moulting prior to the start of the six‐day feeding trial, subsequently died from haemorrhaging five days after the final dose. During the six‐day feeding trial the birds received cumulative flocoumafen doses ranging from 0–78 mg kg−1 to 1‐25 mg kg−1 (0.93 mg kg−1 for the bird which died).By comparison with previous, analogous studies, flocoumafen appears less toxic to Barn Owls than brodifacoum. However, the relative toxicity of flocoumafen, bromadiolone and difenacoum cannot be ascertained from these studies because the dose rates were not comparable.Chemical analysis of regurgitated Barn Owl pellets indicated that a substantial amount (mean 27%) of the consumed flocoumafen was eliminated unchanged in the pellets during the dosing periods. After dosing ceased, the flocoumafen content in pellets decreased rapidly. These data confirm those from a preliminary single‐dose study and substantiate the use of pellet analysis as a sensitive and selective method for non‐invasive monitoring of the exposure of Barn Owls to anticoagulant rodenticides in their prey. Analysis of liver residues from both the owl which died and those which survived indicated that flocoumafen is slowly eliminated from this organ with a terminal elimination (β‐phase) half‐life probably in excess of 100 days.
Feeding deterrence of northern fowl mites (acari: Macronyssidae) by some naturally occurring plant substances
Authors: Carroll John F. 
Published: November 2006

AbstractEighteen of 21 naturally occurring compounds and plant extracts tested in an in‐vitro feeding system deterred northern fowl mites, Ornithonyssus sylviarum (Canestrini and Fanzago), from feeding. At 1.0% (w/v) concentrations in chicken blood, five compounds killed all mites exposed to them. Citronellal and bay extract prevented mite feeding completely at 0.1% concentrations. None of the compounds or extracts had repellent activity when mites were surrounded by a ring of the test material (0–42 mgcm−2) impregnated in filter paper.
Synthesis of pyrethroic acids from natural products and from isomeric compounds: Strategy and practice
Authors: Krief Alain 
Published: November 2006

AbstractPyrethroic acids are essential constituents of the pyrethroids, which are now some of the most powerful commercially available insecticides. A number of syntheses of pyrethroic acids have been published since the elucidation of the structure of chrysanthemic acid, one of the naturally occurring acids present as esters in Chrysanthemum cinerarefolium Vis. This paper reports some results of the stereoselective synthesis of the most biologically active enantiomers of pyrethroic acids obtained over the last five years in our laboratory. Two different approaches, which have been patented by two leading European companies in the agrochemical field, have been carried out simultaneously. The first uses the cheap chiral natural products mannitol and tartaric acid as starting materials and allows the rapid construction of the cyclopropane framework. The second takes advantage of the isomeric relationship between dimethyl dimedone, a readily available, non‐chiral compound and chrysanthemic acid. Enantioselective isomerisation of dimethyl dimedone to (1R)‐cis‐ and (1R)‐trans‐chrysanthemic acid has been achieved successfully using a lipase. These two approaches to the synthesis of chrysanthemic acid are compared with related approaches in the literature, which use other natural products or isomers of chrysanthemic acid as starting materials.
Recent advances in the stereoselective synthesis of L‐phosphinothricin
Authors: Zeiss Hans‐Joachim 
Published: November 2006

AbstractL‐Phosphinothricin, the parent α‐amino acid of the herbicide glufosinate‐ammonium, has been obtained in high enantiomeric purity by three different methods. The stereoselective alkylation of a D‐valine‐derived bis‐lactim ether, followed by the hydrolysis of the heterocyclic intermediate, represents an attractive approach for gram‐scale quantities in the laboratory. Another very efficient access to L‐phosphinothricin consists of the asymmetric hydrogenation of a prochiral α‐acylamido acrylate with a chiral bis‐phosphine‐rhodium catalyst, while the reaction of chiral pre‐built C‐4‐fragments, like L‐vinylglycine or L‐2‐amino‐4‐halobutyric acid, which can be obtained from the inexpensive starting materials L‐aspartic acid and L‐glutamic acid, with (methyl)phosphinic acid derivatives represents a third route which allows the production of nearly enantiomerically pure L‐phosphinothricin.
The synthesis of pyrroles with insecticidal activity
Authors: Kuhn David G. , Kamhi Victor M. , Furch Joseph A. , Diehl Robert E. , Lowen Gregory T. , Kameswaran Venkataraman 
Published: November 2006

AbstractThe 2‐aryl‐4‐bromo‐5‐trifluoromethylpyrrole‐3‐carbonitriles represent a new class of insect control agents. The high insectidical activity observed in this series prompted us to investigate the preparation of regioisomeric arylhalotrifluoromethylpyrrole carbonitriles. The synthesis and biological activity of eight of the twelve possible regioisomers are described and discussed.
Derivatives of pesticides with an α‐amino acid function: Synthesis and effect on threonine uptake
Authors: Dufaud Annie , Chollet Jean‐François , Rudelle Jérǒme , Miginiac Léone , Bonnemain Jean‐Louis 
Published: November 2006

AbstractThe synthesis of several derivatives of a pesticide and an α‐amino acid are described. The process involves three steps, the last one (deprotection of the α‐amino acid group) being the most critical. The resulting products preserved their α‐amino acid group and were globally neutral. They were tested for their effect on the transport of a neutral amino acid, threonine, and two sugars, sucrose and glucose. Two derivatives markedly and specifically inhibited threonine uptake by leaf tissues of Vicia faba L. and phloem loading. Preliminary experiments suggested that the lysine‐2,4‐D derivative is a competitive inhibitor of threonine uptake. The apparent Ki (0.5 mM) was much lower than the apparent Km (3 mm) of the natural substrate.
Non‐invasive method for monitoring the exposure of Barn owls to second‐generation rodenticides
Authors: Gray Alan , Eadsforth Charles V. , Dutton Alan J. , Vaughan John A. 
Published: November 2006

AbstractChemical analysis of rodenticide residues in regurgitated owl pellets has been shown to be a sensitive, non‐invasive method for monitoring the potential exposure of Barn Owls to second‐generation rodenticides in their prey. The method, originally developed for flocoumafen, has been extended to two other rodenticides. brodifacoum and difenacoum.The method was validated as part of a toxicity study in which Barn Owls were separately fed 40–130 μg day −1 of brodifacoum, difenacoum and flocoumafen in mice over 15 days. Each day an average of 25% of the consumed rodenticide was regurgitated in the pellets.
Analysis of human sweat volatiles: An example of pattern recognition in the analysis and interpretation of gas chromatograms
Authors: Sommerville Barbara A. , McCormick James P. , Broom Donald M. 
Published: November 2006

AbstractThe analysis of the volatile components of human body odour is described with a view to establishing how individual identity can be reflected in an odour profile. In order to get good chromatographic replication, a recirculating system was built to load the samples of axillary sweat head‐space into Tenax concentrating traps. The loading temperature and humidity could be controlled and trace volatiles concentrated. The head‐space samples were desorbed from the trap and analysed by GLC. The GC/FID was interfaced with an ATARI ST 1040 computer which stored the output on disc. Pairs of chromatograms were then compared in a pattern‐matching programme which allowed irrelevant differences, such as variations in running time and sample size, to be corrected and then various match parameters to be measured. These were alignment coefficient, profile correlation. Euclidian distance and box car distance. The whole and selected parts of the chromatograms could be matched so that each range of volatiles could be assessed for its contribution to an identity signal.The pattern of sweat volatiles from two pairs of identical twins showed significantly higher match correlations than that of unrelated people. The range of compounds eluting between 80 and 150 C showed the highest match correlations.These techniques could be used to match chromatograms from any source, for example, in drugs and pesticide research, environmental monitoring, food, flavour and perfume analysis or clinical and forensic investigations.
Spectrophotometric determination of ziram and zineb using 4‐(2‐pyridylazo) resorcinol
Authors: Kapoor Jyoti , Rao A. L. J. 
Published: November 2006

AbstractA spectrophotometric method has been developed for the determination of ziram (zinc bis(dimethyldithiocarbamate)) and zineb (zinc ethylenebisdithiocarbarnate) by converting these into a zinc‐4‐(2‐pyridylazo)resorcinol complex, which is dissolved in acetone and water and the absorbance measured at 490 nm against a reagent blank. Beer's law is obeyed over the concentration ranges 0.025‐1.25 and 0.025‐1.5 mg litre−1 for ziram and zineb respectively in the final solution. The method is sensitive and can be used for the direct determination of ziram and zineb in commercial formulations, grains (rice and wheat) and synthetic mixtures (in the presence of various other dithiocarbamates). The limit of determination of ziram and zineb from foodstuffs in 0.2 mg kg −1.
Managing resistance in Bemisia tabaci in Israel with emphasis on cotton
Authors: Horowitz A. Rami , Forer Gadi , Ishaaya Isaac 
Published: November 2006

AbstractAt the beginning of the 1990s, insecticides with novel modes of action, such as buprofezin, pyriproxyfen and diafenthiuron, were introduced for controlling the whitefly Bemisia tabaci (Gennadius) in cotton and other crops. In order to delay the onset of resistance to these novel insecticides, as well as to the efficient conventional ones, an insecticide resistance management (IRM) strategy was implemented in 1987 in cotton fields in Israel. The main purposes have been to combat resistance to available, efficient insecticides and to prolong the life‐span of new insecticides by optimizing their use and preserving natural enemies during the peak of their activity. A rotation programme was applied, using insecticides of different modes of action, rotated according to the generation duration of the relevant pests. The strategy included explanatory and educational campaigns, and was accompanied by an extensive resistance monitoring programme conducted throughout the year in greenhouses and during the summer in cotton fields. Bioassays of whiteflies collected from cotton fields indicated that one treatment with pyriproxyfen in cotton fields during a one‐month period, followed by an additional treatment with buprofezin (if required), did not markedly alter the susceptibility of B. tabaci to either compound. In addition, no appreciable increase of resistance to the available conventional insecticides was observed, although some changes in susceptibility were noticed during the cotton season. In some greenhouses without an IRM programme, a c.tenfold increase in resistance to buprofezin was found after two or three applications of this compound in each season. A c.500‐fold increase of resistance to pyriproxyfen was recorded after three successive applications of this compound in a greenhouse. These findings demonstrate the necessity for an IRM strategy to be implemented in both open fields and greenhouses.
Possible methionine biosynthesis inhibition by pyrimidinamine fungicides
Authors: Masner Petr , Muster Peter , Schmid Jacqueline 
Published: November 2006

AbstractThe broad‐spectrum fungicide CGA 219417 inhibits mycelial growth of Botrytis cinerea Pers ex Fr. Pseudocercosporella herpotrichoides (Fron.) Deighton and Helminthosporium oryzae B. de Haan on defined media lacking amino acids. The growth inhibition of B. cinerea is reversed by the addition of a mixture of 19 amino acids at a concentration of 100 μM each or by the addition of methionine or homocysteine in concentrations of 100 μM or 1 mM, respectively. In the case of B. cinerea, the reversal of growth inhibition by methionine could also be shown for pyrimethanil and mepanipyrim. These findings suggest that the pyrimidinamine fungicides inhibit the biosynthesis of methionine in phytopathogenic fungi.
Insecticidal activity of synthetic 2‐carboxylbenzofurans and their coumarin precursors
Authors: Williams Lawrence A. D. , Anderson Mario J. , Jackson Yvette A. 
Published: November 2006

AbstractSeveral 2‐carboxylbenzofurans and their coumarin precursors, compounds 1–6, and the novel compound 7 were synthesized and their insecticidal activity studied using adult sweet potato weevils (Cylas formicarius elegantulus (Summer)) at 24 μg, 48 μg and 72 μg per insect in 0.5 ml litre−1 piperonyl butoxide (PPB) in acetone. The order of toxicity of the compounds as judged by the percentage mortality at 24 μg per insect at 48 h was 2 (100%) > 6 (95%) > 7 (85%) > 4 (75%)) > 3 (65%) > 1 (60%) > 5 (45%) > piperonyl butoxide (0.0%).Compound 2 was equitoxic to 24 μg of technical grade dimethoate. When administered in acetone alone, however, the compounds were only moderately active (i.e. > 120 μg per insect was required for 60% mortality at 48 h). The test compounds were more active at lower doses (48–72 μg per insect) when dissolved in dimethylsulfoxide or in an oil extract obtained from the fruit of Blighia sapida Koenig.
Detoxification and activation of agrochemicals in plants
Authors: Cole David J. 
Published: November 2006

AbstractPlants are able to metabolize agrochemicals and other foreign compounds by a variety of mechanisms and with extraordinary species diversity. Minor structural alterations of these compounds can bring about dramatic and unpredictable changes in the routes of their metabolism. The enzymes responsible for this exist in multiple forms which renders prediction of herbicide metabolism and, therefore, of selectivity, difficult. In some notable instances, pesticides are activated by plant metabolism. In the main, however, mechanisms such as hydroxylation, dealkylation and glutathione conjugation bring about detoxification and form the basis of herbicide selectivity. The properties of oxygenating and conjugating enzymes in plants are highlighted, with emphasis on the evident narrow substrate specificities, species differences and physiological roles. The molecular cloning of the genes specifying these enzymes will permit a much better definition of these mechanisms and will illuminate the natural roles of the enzymes involved. The prospects for utilizing recombinant enzymes as tools for the rational design of new selective herbicides are discussed. Herbicide safeners can protect certain crops from herbicide injury by promoting herbicide metabolism. The precise mechanisms of safener action and the reasons for their specificity are attracting much interest but are at present obscure. Natural variation in detoxification abilities of weed populations has allowed the field selection of some biotypes resistant to repeatedly used herbicides. By analogy, the introduction of microbial detoxification genes into major crops through genetic transformation has created new herbicideresistant crops which will enhance the flexibility of herbicide usage.
Triazolines. XXIX. 1,5‐diaryl‐Δ2‐1,2,3‐triazolines as aphicides: Mechanism of action via aziridine formation
Authors: Kadaba Pankaja K. 
Published: November 2006

AbstractThe aphicidal activity of 21 different 1,5‐diphenyl‐Δ2‐1,2,3‐triazolines, conveniently prepared utilizing the catalytic effect of water on the 1,3‐cyclo‐addition of diazomethane to Schiff bases in aqueous dioxane, was evaluated. Triazolines bearing an o‐Cl substituent on the C‐phenyl, either alone (4) or in combination with a m‐ and/or a p‐substituent on the N‐phenyl (14, 15, 17 and 18), showed significant activity, with a combined m‐, p‐ substitution on the N‐phenyl the most effective (17 and 18). While an o‐Cl substituent led to greater activity than an o‐NO2 group, the introduction of an additional p‐Cl substituent on the C‐phenyl eliminated activity (21).The aphicidal activity of triazoline 18 was found to be dependent on the presence of UV light. Since fluorescent lighting used in the testing procedure contains UV light and since triazolines undergo photolysis when exposed to UV light to yield aziridines, it was logical to conclude that the aphicidal activity of the triazolines was, in fact, derived from the aziridines formed during the testing procedure. This mechanism of action was confirmed by preparing the aziridines 22, 23 and 24 corresponding to the active triazolines 14, 15 and 18, and showing that they possessed aphicidal activity equal to or better than that of the triazolines, and by the activity observed in several other structurally related aziridine analogues (25–28). Unlike aziridinyl phosphorous compounds, the aziridines described here are not mutagenic in the Ames assay and thus afford a safer class of pesticides.
A survey comparing the chemical composition of dicofol formulations sold in the UK before and after the introduction of the EC ‘prohibition directive 79/117/EEC’
Authors: Gillespie Margaret J. , Lythgo Christopher M. , Plumb Andrew D. , Wilkins John P. G. 
Published: November 2006

AbstractAnalysis of 38 formulations marketed by five companies indicated that the active ingredient contents of these products are within the range of 92 to 112%, for dicofol, and 107 to 142%, for tetradifon, of that declared. Manufacturing procedures for dicofol produce impurities related to DDT. The adoption of a prohibition directive in Europe requires that DDT‐related impurities represent less than 1 g kg−1 of the dicofol content. Formulations manufactured before the prohibition directive contained these impurities at up to 575 g kg−1 of the dicofol in the formulation. Formulations manufactured after the directive contained these impurities at up to 7 g kg−1 of the dicofol in the formulation. Fewer impurities were detected in the more recent formulations; only o,o′‐DDE, o,m′‐DDE, o,p′‐DDE, m,p′‐DDE, p,p′‐DDE, o,p′‐chloro‐DDT and p,p′‐chloro‐DDT were present. Eight of the 13 samples contained DDT‐related impurities at less than 0.1 g kg−1 of the dicofol in the formulation. The major impurities found in formulations manufactured after the directive (in concentration terms) are non DDT‐related manufacturing byproducts such as o,p′‐dichlorobenzil.