28 research outputs found

    Reaction of a triazolinedione with simple alkenes: isolation and characterization of hydration products

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    The reaction of N-phenyltriazolinedione with three simple alkyl-substituted alkenes in water/alcohol or water/acetone solution was found to give a mixture of the corresponding ene and water addition products. The new hydration products were characterized by spectroscopy, and in one case, also by X-ray diffraction analysis. Thermodynamic parameters were determined for the reactions involving 2-methylbut-2-ene, TriME, and 2,3-dimethylbut-2-ene, TetraMe, in accordance with an ‘SN2-like’, nucleophilic attack on a closed aziridinium imide (AI) intermediate by water

    Erratum to: Laboratory evaluation of five novel pyrrole derivatives as grain protectants against Tribolium confusum and Ephestia kuehniella larvae (Journal of Pest Science, (2017), 90, 2, (569-585), 10.1007/s10340-016-0808-x)

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    Volume and page range of one of the references were published incorrectly in the original publication of the article. The correct volume for Boukouvala et al. (2016b) is 84. The correct page range for Boukouvala et al. (2016b) is 1-7. © 2016, Springer-Verlag Berlin Heidelberg

    Laboratory evaluation of five novel pyrrole derivatives as grain protectants against Tribolium confusum and Ephestia kuehniella larvae

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    Several naturally discovered or laboratory-synthesized pyrrole compounds have insecticidal, acaricidal and microbial properties. The novel sulfanyl 5H-dihydro-pyrrole derivatives exhibit certain antioxidant activities. However, there is a knowledge gap whether these substances are potent grain protectants against stored-product insect pest species. In this context, we evaluated the insecticidal activity of five novel pyrrole derivatives (under the trivial names 3a, 3g, 3l, 3m, 3h), against larvae of Tribolium confusum Jaquelin du Val and Ephestia kuehniella Zeller at different doses (0.1, 1 and 10 ppm), exposure intervals (7, 14 and 21 days or 1, 2, 7, 14, 21 days), temperatures (20, 25 and 30 °C), relative humidity (RH) (55 and 75 %) levels and commodities (wheat, maize, barley). The pyrrole derivative 3a exhibited the highest insecticidal activity, while 3g, 3l, 3m and 3h caused similar mortality against larvae of T. confusum. Apart of the level of efficacy, all tested pyrrole derivatives performed similarly according temperature. We found that increase in temperature increased mortality in the majority of the tested combinations. Generally, the pyrrole derivatives caused the highest mortality levels at 30 °C. The pyrrole derivatives 3a, 3g, 3l and 3m were affected by relative humidity at almost all combinations tested. The 75 % level of RH moderated the efficacy of the pyrrole derivatives, while the 55 % enhanced it. Mortality of T. confusum and E. kuehniella on maize was much lower on treated maize than barley or wheat. However, 100 % control of both species was recorded only on treated barley. The results of the present study indicate that the pyrrole derivatives tested could serve as grain protectants against noxious stored-product insects under certain biotic and abiotic conditions.Maria C. Boukouvala, Nickolas G. Kavallieratos, Christos G. Athanassiou, Dusan Losic, Lazaros P. Hadjiarapoglou, Yiannis Eleme

    Laboratory evaluation of five novel pyrrole derivatives as grain protectants against Tribolium confusum and Ephestia kuehniella larvae

    No full text
    Several naturally discovered or laboratory-synthesized pyrrole compounds have insecticidal, acaricidal and microbial properties. The novel sulfanyl 5H-dihydropyrrole derivatives exhibit certain antioxidant activities. However, there is a knowledge gap whether these substances are potent grain protectants against stored-product insect pest species. In this context, we evaluated the insecticidal activity of five novel pyrrole derivatives (under the trivial names 3a, 3g, 3l, 3m, 3h), against larvae of Tribolium confusum Jaquelin du Val and Ephestia kuehniella Zeller at different doses (0.1, 1 and 10 ppm), exposure intervals (7, 14 and 21 days or 1, 2, 7, 14, 21 days), temperatures (20, 25 and 30 °C), relative humidity (RH) (55 and 75 %) levels and commodities (wheat, maize, barley). The pyrrole derivative 3a exhibited the highest insecticidal activity, while 3g, 3l, 3m and 3h caused similar mortality against larvae of T. confusum. Apart of the level of efficacy, all tested pyrrole derivatives performed similarly according temperature. We found that increase in temperature increased mortality in the majority of the tested combinations. Generally, the pyrrole derivatives caused the highest mortality levels at 30 °C. The pyrrole derivatives 3a, 3g, 3l and 3m were affected by relative humidity at almost all combinations tested. The 75 % level of RH moderated the efficacy of the pyrrole derivatives, while the 55 % enhanced it. Mortality of T. confusum and E. kuehniella on maize was much lower on treated maize than barley or wheat. However, 100 % control of both species was recorded only on treated barley. The results of the present study indicate that the pyrrole derivatives tested could serve as grain protectants against noxious stored-product insects under certain biotic and abiotic conditions. © Springer-Verlag Berlin Heidelberg 2016

    Solvent-trap reaction of triazolinediones with simple alkenes: An experimental/theoretical study of thermodynamic and kinetic parameters

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    6siThe reaction of N-phenyltriazolinedione with simple alkyl-substituted alkenes in a series of simple alcohols as nucleophilic solvents affords two products: a solvent-addition product (trap) and the ene adduct. Herein we present different experimental data which allow the estimation of different kinetic parameters ( DDHs ene,trap and DDSs ene,trap). The values of those parameters are found to be lower with a longer nucleophile-solvent molecule. Solvent isotope effects are also estimated and found in favour of the heavier (and smaller) deuterated compounds. Results from competition experiments in equimolar binary mixtures of different alcohols as solvents also point to the prevalence of the smaller alcohol. A length limitation is observed in the competition of EtOH versus PrOH couple, the absence of any competition for the formation of the two solvent-addition (trap) products. All the results are consistent with an SN2-‘like’ nucleophilic attack of the nucleophile-solvent to a closed aziridinium imide (AI) intermediate. Computational models were investigated in order to both confirm the stability of the different possible intermediates and to confirm the experimentally observed trends and kinetic profiles. Furthermore, the results show the existence of a single transition state from which both products are formed.This work is dedicated to the memory of Professor Yiannis ElemesreservedmixedKoutsianopoulos, Fotios; Bonasera, Aurelio; Osella, Silvio; Lazzaroni, Roberto; Syrgiannis, Zois; Elemes, YiannisKoutsianopoulos, Fotios; Bonasera, Aurelio; Osella, Silvio; Lazzaroni, Roberto; Syrgiannis, Zois; Elemes, Yianni

    Synthesis of a proline-rich [60]fullerene peptide with potential biological activity

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    A proline-rich 60fullerene peptide was synthesized by use of (i) a 1,3-dipolar cycloaddn. of an N-substituted glycine deriv. to 60fullerene (F60), (ii) esterification of the isolated alc. with the C-terminal amino acid of the desired peptide sequence, and finally (iii) coupling of the remaining hexapeptide to give the final product H-Pro-Pro-Gly-Met-Arg-Pro-Pro-O(CH2)2O(CH2)2N(CH2)2-F60 as a TFA salt, with oxidized methionine (I). Product I was found to be biol. active against sera from MCTD (Mixed connective Tissue Disease) and SLE (Systemic Lupus Erythematosus) patients (ELISA expt.)
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