The Experts below are selected from a list of 1566 Experts worldwide ranked by ideXlab platform
Xiaoyan Zhi - One of the best experts on this subject based on the ideXlab platform.
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Synthesis of benzoxazole derivatives of honokiol as insecticidal agents against Mythimna separata Walker.
Bioorganic & medicinal chemistry letters, 2015Co-Authors: Chun Yang, Xiaoyan ZhiAbstract:A series of novel benzoxazole compounds derived from a naturally occurring neolignan honokiol were prepared. Their insecticidal activity was tested against the pre-third-instar larvae of oriental armyworm (Mythimna separata Walker) in vivo. Most of the tested derivatives exhibited more potential insecticidal activity than their precursor honokiol at the concentration of 1mg/mL. Especially compound 6e, containing 4-acetyloxyphenyl groups at the C8 and C8' positions, displayed the most potent insecticidal activity with the final mortality rate of 62.1%.
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Semisynthesis and insecticidal activity of arylmethylamine derivatives of the neolignan honokiol against Mythimna separata Walker
Zeitschrift fur Naturforschung - Section C Journal of Biosciences, 2015Co-Authors: Chun Yang, Xiaoyan Zhi, Hui XuAbstract:A series of novel arylmethylamine derivatives of honokiol (5a-m) was prepared. Their insecticidal activity was tested against the pre-third-instar larvae of the oriental armyworm (Mythimna separata Walker), a typical lepidopteran pest. Compounds 5a, 5b, 5e, 5h, and 5k exhibited insecticidal activity equal to, or higher than, that of the positive control toosendanin.
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Insight into reduction of obacunone, and their ester derivatives as insecticidal agents against Mythimna separata Walker.
Bioorganic & medicinal chemistry letters, 2014Co-Authors: Guodong Ding, Xiaoyan ZhiAbstract:Here we have prepared a series of ester compounds of obacunone, a naturally occurring limonoid, isolated from plants such as Citrus and Dictamnus angustifolius. Their insecticidal activity was evaluated at 1 mg/mL against the pre-third-instar larvae of oriental armyworm (Mythimna separata Walker), a typical lepidopteran pest. When obacunone reacted with NaBH₄, the ratio of two reduction products, C7α-hydroxyobacunone (2) and C7β-hydroxyobacunone (3), was related to the reaction mixing solvents. C7α-Propionyloxybacunone (4b) and C7β-(n)heptanoyloxybacunone (5g) exhibited the more promising insecticidal activity than their precursor obacunone and toosendanin.
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Synthesis and insecticidal activity of new oxime derivatives of podophyllotoxin-based phenazines against Mythimna separata Walker
Bioorganic & medicinal chemistry letters, 2014Co-Authors: Xiaoyan Zhi, Chun YangAbstract:To discover new natural-product-based insecticidal agents, a series of novel oxime derivatives of podophyllotoxin-based phenazines modified in the C, D and E rings of podophyllotoxin were prepared and tested as insecticidal agents against the pre-third-instar larvae of oriental armyworm, Mythimna separata (Walker) in vivo at 1 mg/mL. The steric configuration of IIIc was unambiguously confirmed by single-crystal X-ray diffraction analysis. Compounds IIIa-d, and IIIi exhibited an equal or higher insecticidal activity than toosendanin.
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Synthesis and insecticidal activity of novel hydrazone compounds derived from a naturally occurring lignan podophyllotoxin against Mythimna separata (Walker).
Bioorganic & medicinal chemistry letters, 2014Co-Authors: Yi Wang, Xiaoyan Zhi, Xiao Xiao, Chun YangAbstract:In continuation of our program aimed at the discovery and development of natural-product-based insecticidal agents, a series of novel hydrazone derivatives of podophyllotoxin, which is a naturally occurring aryltetralin lignan and isolated as the main secondary metabolite from the roots and rhizomes of Podophyllum species, were synthesized and evaluated as insecticidal agents against the pre-third-instar larvae of oriental armyworm, Mythimna separata (Walker) in vivo at 1mg/mL. Especially compounds 8i, 8j, 8t, and 8u showed the more potent insecticidal activity with the final mortality rates greater than 60%.
Juanjuan Wang - One of the best experts on this subject based on the ideXlab platform.
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Synthesis and insecticidal activity of new deoxypodophyllotoxin-based phenazine analogues against Mythimna separata Walker.
Journal of agricultural and food chemistry, 2013Co-Authors: Juanjuan Wang, Xiaoyan ZhiAbstract:In continuation of our program aimed at the discovery and development of natural-product-based insecticidal agents, a series of new deoxypodophyllotoxin-based phenazine analogues modified in their E-ring were prepared, and their structures were well characterized by 1H NMR, HRMS, ESI-MS, IR, optical rotation, and mp. The absolute steric configuration of one key isomer was unambiguously confirmed by X-ray crystallography. Their insecticidal activity was examined against the pre-third-instar larvae of oriental armyworm, Mythimna separata (Walker) in vivo at the concentration of 1 mg/mL. All derivatives showed delayed insecticidal activity. Especially compound 9i, containing p-methoxybenzoylamnio at the C-9′ position of deoxypodophyllotoxin-based phenazine fragment, exhibited the most promising insecticidal activity with the final mortality rate of 72.4%. According to the symptoms of the tested M. separata, the derivatives likely displayed an antimolting hormone effect. In addition, preliminary structure–act...
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natural products based insecticidal agents 5 design semisynthesis and insecticidal activity of novel 4 substituted benzenesulfonate derivatives of 4 deoxypodophyllotoxin against Mythimna separata walker in vivo
Bioorganic & Medicinal Chemistry Letters, 2010Co-Authors: Juanjuan WangAbstract:Abstract In an attempt to find the effective phytopesticides, eight novel 4′-substituted benzenesulfonate derivatives of 4-deoxypodophyllotoxin were synthesized and preliminarily tested against the pre-third-instar larvae of Mythimna separata Walker in vivo at the concentration of 1 mg/mL. Among all of the tested analogs, compounds 5a , 5c , 5d , and 5h showed the higher insecticidal activity than 4-deoxypodophyllotoxin. Especially 5a exhibited the most potent insecticidal activity compared with toosendanin, a commercial insecticide derived from Melia azedarach .
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Natural products-based insecticidal agents 5. Design, semisynthesis and insecticidal activity of novel 4′-substituted benzenesulfonate derivatives of 4-deoxypodophyllotoxin against Mythimna separata Walker in vivo.
Bioorganic & medicinal chemistry letters, 2010Co-Authors: Juanjuan WangAbstract:Abstract In an attempt to find the effective phytopesticides, eight novel 4′-substituted benzenesulfonate derivatives of 4-deoxypodophyllotoxin were synthesized and preliminarily tested against the pre-third-instar larvae of Mythimna separata Walker in vivo at the concentration of 1 mg/mL. Among all of the tested analogs, compounds 5a , 5c , 5d , and 5h showed the higher insecticidal activity than 4-deoxypodophyllotoxin. Especially 5a exhibited the most potent insecticidal activity compared with toosendanin, a commercial insecticide derived from Melia azedarach .
Chun Yang - One of the best experts on this subject based on the ideXlab platform.
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Synthesis of benzoxazole derivatives of honokiol as insecticidal agents against Mythimna separata Walker.
Bioorganic & medicinal chemistry letters, 2015Co-Authors: Chun Yang, Xiaoyan ZhiAbstract:A series of novel benzoxazole compounds derived from a naturally occurring neolignan honokiol were prepared. Their insecticidal activity was tested against the pre-third-instar larvae of oriental armyworm (Mythimna separata Walker) in vivo. Most of the tested derivatives exhibited more potential insecticidal activity than their precursor honokiol at the concentration of 1mg/mL. Especially compound 6e, containing 4-acetyloxyphenyl groups at the C8 and C8' positions, displayed the most potent insecticidal activity with the final mortality rate of 62.1%.
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Semisynthesis and insecticidal activity of arylmethylamine derivatives of the neolignan honokiol against Mythimna separata Walker
Zeitschrift fur Naturforschung - Section C Journal of Biosciences, 2015Co-Authors: Chun Yang, Xiaoyan Zhi, Hui XuAbstract:A series of novel arylmethylamine derivatives of honokiol (5a-m) was prepared. Their insecticidal activity was tested against the pre-third-instar larvae of the oriental armyworm (Mythimna separata Walker), a typical lepidopteran pest. Compounds 5a, 5b, 5e, 5h, and 5k exhibited insecticidal activity equal to, or higher than, that of the positive control toosendanin.
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Synthesis and insecticidal activity of new oxime derivatives of podophyllotoxin-based phenazines against Mythimna separata Walker
Bioorganic & medicinal chemistry letters, 2014Co-Authors: Xiaoyan Zhi, Chun YangAbstract:To discover new natural-product-based insecticidal agents, a series of novel oxime derivatives of podophyllotoxin-based phenazines modified in the C, D and E rings of podophyllotoxin were prepared and tested as insecticidal agents against the pre-third-instar larvae of oriental armyworm, Mythimna separata (Walker) in vivo at 1 mg/mL. The steric configuration of IIIc was unambiguously confirmed by single-crystal X-ray diffraction analysis. Compounds IIIa-d, and IIIi exhibited an equal or higher insecticidal activity than toosendanin.
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Synthesis and insecticidal activity of novel hydrazone compounds derived from a naturally occurring lignan podophyllotoxin against Mythimna separata (Walker).
Bioorganic & medicinal chemistry letters, 2014Co-Authors: Yi Wang, Xiaoyan Zhi, Xiao Xiao, Chun YangAbstract:In continuation of our program aimed at the discovery and development of natural-product-based insecticidal agents, a series of novel hydrazone derivatives of podophyllotoxin, which is a naturally occurring aryltetralin lignan and isolated as the main secondary metabolite from the roots and rhizomes of Podophyllum species, were synthesized and evaluated as insecticidal agents against the pre-third-instar larvae of oriental armyworm, Mythimna separata (Walker) in vivo at 1mg/mL. Especially compounds 8i, 8j, 8t, and 8u showed the more potent insecticidal activity with the final mortality rates greater than 60%.
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Synthesis of 4β-acyloxypodophyllotoxin analogs modified in the C and E rings as insecticidal agents against Mythimna separata Walker
Bioorganic & medicinal chemistry letters, 2014Co-Authors: Xiaoyan Zhi, Chun Yang, Guodong Ding, Hui ChenAbstract:To discover the new natural-product-based insecticidal agents, four series of sixty novel 4β-acyloxypodophyllotoxin analogs modified in the C and E rings were prepared, and their insecticidal activity was tested against the pre-third-instar larvae of oriental armyworm, Mythimna separata (Walker) in vivo at the concentration of 1 mg/mL. It demonstrated that the position of the dioxo group on the E-ring of 4'-demethylepipodophyllotoxin was regioselectively controlled by the chlorine atom at its C-2' position when 2'-chloro-4'-demethylepipodophyllotoxin was oxidized by sodium periodate. Among all the derivatives, IIIi exhibited the best potent insecticidal activity with the final mortality rate of 63.3%. To alkylacyloxy series, the proper length of the side chain at the C-4 position of Ia-g, IIa-g and IIIa-g was important for their insecticidal activity.
Xiao Xiao - One of the best experts on this subject based on the ideXlab platform.
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Synthesis and insecticidal activity of novel hydrazone compounds derived from a naturally occurring lignan podophyllotoxin against Mythimna separata (Walker).
Bioorganic & medicinal chemistry letters, 2014Co-Authors: Yi Wang, Xiaoyan Zhi, Xiao Xiao, Chun YangAbstract:In continuation of our program aimed at the discovery and development of natural-product-based insecticidal agents, a series of novel hydrazone derivatives of podophyllotoxin, which is a naturally occurring aryltetralin lignan and isolated as the main secondary metabolite from the roots and rhizomes of Podophyllum species, were synthesized and evaluated as insecticidal agents against the pre-third-instar larvae of oriental armyworm, Mythimna separata (Walker) in vivo at 1mg/mL. Especially compounds 8i, 8j, 8t, and 8u showed the more potent insecticidal activity with the final mortality rates greater than 60%.
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Natural products-based insecticidal agents 7. Semisynthesis and insecticidal activity of novel 4α-alkyloxy-2-chloropodophyllotoxin derivatives against Mythimna separata Walker in vivo.
Bioorganic & medicinal chemistry letters, 2010Co-Authors: Xiao Xiao, Qing-tian WangAbstract:In continuation of our program aimed at the discovery and development of natural products-based insecticidal agents, 16 novel 4alpha-alkyloxy-2-chloropodophyllotoxin derivatives were semisynthesized from podophyllotoxin, and preliminarily evaluated for their insecticidal activity against the pre-third-instar larvae of Mythimna separata Walker in vivo. Among all the tested derivatives, especially compounds 4b, 4e, 4g, and 4p exhibited more promising and pronounced insecticidal activity than toosendanin, a commercial insecticide derived from Melia azedarach. Generally, it was obviously demonstrated that the length of straight-chain or branched-chain alkyloxy, and heteroatom-containing cycloalkyloxy at the C-4 position of 2-chloropodophyllotoxin were very important for the insecticidal activity.
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Natural products-based insecticidal agents 4. Semisynthesis and insecticidal activity of novel esters of 2-chloropodophyllotoxin against Mythimna separata Walker in vivo
Bioorganic & medicinal chemistry letters, 2009Co-Authors: Xiao XiaoAbstract:By using podophyllotoxin as a lead compound, eight novel esters of 2-chloropodophyllotoxin were designed, semisynthesized, and preliminarily evaluated for their insecticidal activity against the pre-third-instar larvae of Mythimna separata Walker in vivo for the first time. Among all the tested compounds, especially three esters of 2-chloropodophyllotoxin 8a, 8c, and 8g, and one intermediate 6 showed more promising and pronounced insecticidal activity than toosendanin, a commercial insecticide derived from Melia azedarach.
Junliang Zhang - One of the best experts on this subject based on the ideXlab platform.
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natural products based insecticidal agents 11 synthesis and insecticidal activity of novel 4α arylsulfonyloxybenzyloxy 2β chloropodophyllotoxin derivatives against Mythimna separata walker in vivo
Bioorganic & Medicinal Chemistry Letters, 2011Co-Authors: Junliang ZhangAbstract:Abstract In continuation of our program aimed at the discovery and development of natural products-based insecticidal agents, 14 novel 4α-arylsulfonyloxybenzyloxy-2β-chloropodophyllotoxin derivatives were stereoselectively semisynthesized from podophyllotoxin, and preliminarily evaluated for their insecticidal activity against the pre-third-instar larvae of Mythimna separata Walker in vivo. Especially compounds 9c′ and 9g′ exhibited the most promising and pronounced insecticidal activity than toosendanin, a commercial insecticide derived from Melia azedarach at 1 mg/mL. Generally, it was preliminarily demonstrated that arylsulfonyloxy groups at the C-2 position of benzyloxy moiety and the length of the side chain on the benzenesulfonyloxy group of 4α-arylsulfonyloxybenzyloxy-2β-chloropodophyllotoxins might be important for the insecticidal activity.
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Natural products-based insecticidal agents 9. Design, semisynthesis and insecticidal activity of 28-acyloxy derivatives of toosendanin against Mythimna separata Walker in vivo
Bioorganic & medicinal chemistry letters, 2011Co-Authors: Junliang ZhangAbstract:In continuation of our program aimed at the discovery and development of natural products-based insecticidal agents, twelve 28-acyloxy derivatives of toosendanin (2a-l) were semisynthesized and preliminarily evaluated their activity against the pre-third-instar larvae of Mythimna separata Walker in vivo at the concentration of 1mg/mL. Some compounds exhibited the potent insecticidal activity. Especially compounds 2c and 2j displayed the more promising insecticidal activity than their natural precursor, toosendanin, a commercial insecticide derived from Melia azedarach at 1mg/mL. In general, it indicated that the butanoyloxy or phenylacryloyloxy moiety at the 28-position of toosendanin was essential for the insecticidal activity.