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Jian-min Yue - One of the best experts on this subject based on the ideXlab platform.
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Dysohonin A, a meroditerpenoid incorporating a 6,15,6-fused heterotricyclic ring system from Dysoxylum hongkongense
Organic Chemistry Frontiers, 2018Co-Authors: Jinxin Zhao, Cui-ping Liu, Meng-meng Zhang, Jian-min YueAbstract:Dysohonin A (1), a meroditerpenoid incorporating an unprecedented 6,15,6-fused heterotricyclic ring system, along with three new biogenetically related meroditerpenoids dysohonins B–D (2–4) were isolated from Dysoxylum hongkongense. Their structures with absolute configurations were well established by a combined method. The plausible biosynthetic pathways of 1–4 were proposed. All the compounds exhibited PTP1B inhibitory activities.
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Dysoxylumasins a f six new limonoids from Dysoxylum mollissimum bl
Chinese Journal of Chemistry, 2013Co-Authors: Sheng-ping Yang, Jian-min YueAbstract:Six new mexicanolide-type limonoids, Dysoxylumasins A–F (1–6), together with eight known compounds, namely litseagermacrane, 15-methoxyisodauc-3-ene-1β,5α-diol, isodauc-6-ene-10β,14-diol, 4-epi-isodauc-6-ene-10β,14-diol, 2α,3α,4β-trihydroxypregnan-16-one, 1,7-phenanthrenedimethanol, spicatin, and aurantiamide, were isolated from the leaves and twigs of Dysoxylum mollissimum Bl. Their structures were established by the analyses of spectroscopic data.
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Dysoxylumasins A–F: Six New Limonoids from Dysoxylum mollissimum Bl.
Chinese Journal of Chemistry, 2012Co-Authors: Sheng-ping Yang, Jian-min YueAbstract:Six new mexicanolide-type limonoids, Dysoxylumasins A–F (1–6), together with eight known compounds, namely litseagermacrane, 15-methoxyisodauc-3-ene-1β,5α-diol, isodauc-6-ene-10β,14-diol, 4-epi-isodauc-6-ene-10β,14-diol, 2α,3α,4β-trihydroxypregnan-16-one, 1,7-phenanthrenedimethanol, spicatin, and aurantiamide, were isolated from the leaves and twigs of Dysoxylum mollissimum Bl. Their structures were established by the analyses of spectroscopic data.
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Sesquiterpenes from Dysoxylum oliganthum and Dysoxylum excelsum.
Journal of Asian natural products research, 2012Co-Authors: Hong-bing Liu, Chuan-rui Zhang, Shi-hui Dong, Sheng-ping Yang, Qi Sun, Meiyu Geng, Jian-min YueAbstract:Three new sesquiterpenes (1–3), (6R,7S,11R,10S)-15-hydroxy-sesquisabinene hydrate (1), (6R,7R,11S,10S)-15-hydroxy-sesquisabinene hydrate (2), and (6R,7R,10S)-15-hydroxy-zingiberenol (3), along with three known compounds, were isolated from the stems of Dysoxylum oliganthum; and three new isodaucane (salvionane) sesquiterpenes, namely isodauc-6-ene-10β,14-diol (4), 4-epi-isodauc-6-ene-10β,14-diol (5), and 4-epi-6α,10β-dihydroxy-artabotrol (6) together with 15 known compounds were isolated from the twigs and leaves of D. excelsum. Their structures were established on the basis of extensive spectroscopic analysis and chemical shifts. The absolute configuration of C-10 in compounds 1–3 of a rare class was determined by using Snatzke's method.
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Terpenoids from Dysoxylum densiflorum
Phytochemistry, 2008Co-Authors: Bo-jun Xie, Sheng-ping Yang, Jian-min YueAbstract:Three degraded limonoids, dysodensiols A-C (1-3), and three sesquiterpenoids, dysodensiols D-F (4-6), along with 17 known compounds, were isolated from the twigs and leaves of Dysoxylum densiflorum. The structures of compounds 1-6 were established on the basis of extensive spectroscopic analysis.
Vladimir V. Kouznetsov - One of the best experts on this subject based on the ideXlab platform.
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Biomimetic Total Synthesis of Dysoxylum Alkaloids.
The Journal of organic chemistry, 2019Co-Authors: Carlos E. Puerto Galvis, Vladimir V. KouznetsovAbstract:A five-step total synthesis of Dysoxylum alkaloids has been achieved using a biomimetic approach from zanthoxylamide protoalkaloids. The synthesis featured a direct amidation and a Bischler–Napiera...
G. Jayakumar - One of the best experts on this subject based on the ideXlab platform.
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Larvicidal and growth inhibition of the malaria vector Anopheles stephensi by triterpenes from Dysoxylum malabaricum and Dysoxylum beddomei.
Fitoterapia, 2007Co-Authors: Sengottayan Senthil Nathan, A. Hisham, G. JayakumarAbstract:Secondary metabolites from Dysoxylum malabaricum and Dysoxylum beddomei were tested against mature and immature stage of the mosquito vector Anopheles stephensi under laboratory conditions. The triterpenes 3β,24,25-trihydroxycycloartane and beddomeilactone from D. malabaricum and D. beddomei showed strong larvicidal, pupicidal and adulticidal activity. They also affected the reproductive potential of adults by acting as oviposition deterrents. The highest concentration tested (10 ppm) of both compounds evoked more than 90% mortality and oviposition deterrence.
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Beddomeilactone: a new triterpene from Dysoxylum beddomei.
Natural product research, 2004Co-Authors: Abdulkhader Hisham, G. Jayakumar, M.d. Ajitha Bai, Yoshinori FujimotoAbstract:An investigation of the leaves of Dysoxylum beddomei has yielded a novel triterpene, named beddomeilactone, together with six known triterpenoids: 3-oxotirucalla-7,24-dien-23-ol, dipterocarpol, niloticin, melianone, melianodiol and 24-epi-melianodiol. The structure and stereochemistry of the new compound were determined on the basis of mass, 1D and 2D NMR spectroscopies including NOE difference and spin–spin decoupling studies.
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Microwave assisted acetylation and deacetylation studies on the triterpenes isolated from Dysoxylum malabaricum and Dysoxylum beddomei
Indian Journal of Chemistry Section B-organic Chemistry Including Medicinal Chemistry, 2003Co-Authors: G. Jayakumar, M. D. Ajithabai, B. Santhosh, C. S. Veena, Mangalam S. NairAbstract:Phytochemical investigations on the leaves of Dysoxylum malabaricum and Dysoxylum beddomei result in the isolation of a number of triterpenes. Acetylation and deacetylation studies on some of the representative triterpenes show appreciable rate enhancement and increase of yield in the presence of microwave radiation. Details of isolation of triterpenes, acetylation and deacetylation procedures and their results form the subject of the paper. Triterpenes of three skeletal types namely lupane, tirucallane and cycloartane are examined. All the triterpenes examined indicate an increase of cytotoxicity with acetylation.
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Triterpenoids from Dysoxylum malabaricum.
Phytochemistry, 2001Co-Authors: A. Hisham, G. Jayakumar, Mangalam S. Nair, M.d. Ajitha Bai, Yoshinori FujimotoAbstract:Two triterpenes 21R,23R-epoxy-21alpha-ethoxy-24S,25-dihydroxyapotirucall-7-en-3-one and 24R-acetoxy-3beta,25-dihydroxycycloartane were isolated from the leaves of Dysoxylum malabaricum together with eight known compounds lupeone, lupeol. sitosterol, dipterocarpol, cycloart-25-ene-3beta,24-diol, 24R,25-dihydroxycycloartan-3-one, 3beta,24R,25-trihydroxycycloartane and ergosta-5,24(24(1))-diene-3beta,4beta,20S-triol. The complete 1H and 13C NMR spectral assignment of the new apotirucallene triterpenoid has been achieved by 1H-1H COSY, HMQC and HMBC experiments.
C. J. Burrows - One of the best experts on this subject based on the ideXlab platform.
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germination behaviour of seeds of the new zealand woody species beilschmiedia tawa Dysoxylum spectabile griselinia luck a and weinmannia racemosa
New Zealand Journal of Botany, 1999Co-Authors: C. J. BurrowsAbstract:Abstract Germination rates, percentage germination success, and some aspects of germination delay were examined for seeds of four species, taken from freshly collected fruit. In a treatment where seeds were cleaned of pericarp, kept moist, and in maximum available daylight, germination was relatively rapid for all species, during autumn‐winter, with a high degree of success (Weinmannia 85%, the others 96—100%). In the dark, germination rate was slower for Beilschmiedia and Griselinia but the success was similar. Dysoxylum seeds died in the dark, possibly because they were too wet. Germination of nearly all Weinmannia seeds was inhibited in the dark but they germinated well when put into the light. Germination on soil was also relatively slow, but moderately to highly successful for each species except Weinmannia. No seeds of Beilschmiedia, Dysoxylum, or Griselinia germinated in‐fruit, or in a treatment where the cleaned seeds were kept dry for several months before being wetted. Dried Weinmannia seeds ger...
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Germination behaviour of seeds of the New Zealand woody species Beilschmiedia tawa, Dysoxylum spectabile, Griselinia luck/a, and Weinmannia racemosa
New Zealand Journal of Botany, 1999Co-Authors: C. J. BurrowsAbstract:Abstract Germination rates, percentage germination success, and some aspects of germination delay were examined for seeds of four species, taken from freshly collected fruit. In a treatment where seeds were cleaned of pericarp, kept moist, and in maximum available daylight, germination was relatively rapid for all species, during autumn‐winter, with a high degree of success (Weinmannia 85%, the others 96—100%). In the dark, germination rate was slower for Beilschmiedia and Griselinia but the success was similar. Dysoxylum seeds died in the dark, possibly because they were too wet. Germination of nearly all Weinmannia seeds was inhibited in the dark but they germinated well when put into the light. Germination on soil was also relatively slow, but moderately to highly successful for each species except Weinmannia. No seeds of Beilschmiedia, Dysoxylum, or Griselinia germinated in‐fruit, or in a treatment where the cleaned seeds were kept dry for several months before being wetted. Dried Weinmannia seeds ger...
Carlos E. Puerto Galvis - One of the best experts on this subject based on the ideXlab platform.
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Biomimetic Total Synthesis of Dysoxylum Alkaloids.
The Journal of organic chemistry, 2019Co-Authors: Carlos E. Puerto Galvis, Vladimir V. KouznetsovAbstract:A five-step total synthesis of Dysoxylum alkaloids has been achieved using a biomimetic approach from zanthoxylamide protoalkaloids. The synthesis featured a direct amidation and a Bischler–Napiera...