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Françoise Guéritte - One of the best experts on this subject based on the ideXlab platform.
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ugandenial a a new Drimane type sesquiterpenoid from warburgia ugandensis
Molecules, 2009Co-Authors: Min Xu, Bernard Turyagenda Kiremire, John M Kasenene, Sabrina Krief, Marietherese Martin, Vincent Dumontet, Marc Litaudon, Françoise GuéritteAbstract:One new Drimane-type sesquiterpenoid, named ugandenial A ( 1), was isolated from the ethyl acetate extract of the bark of Warburgia ugandensis (Canellaceae) together with eight known Drimane-type sesquiterpenoids: 11 alpha-hydroxycinnamosmolide ( 2), warburganal ( 3), polygodial ( 4), mukaadial ( 5), dendocarbin A ( 6), 9 alpha-hydroxycinnamolide ( 7), dendocarbin L ( 8) and dendocarbin M ( 9). Their structures were established by detailed spectroscopic analysis. In addition a keto-enol equilibrium was demonstrated for compound 1 through a detailed NMR analysis run in CD(2)Cl(2) at 190 K. Cytotoxicity of the isolated compounds against KB cells was evaluated.
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Cytotoxic sesquiterpenoids from Winteraceae of Caledonian rainforest.
Phytochemistry, 2009Co-Authors: Noureddine Allouche, Marietherese Martin, Vincent Dumontet, Françoise Guéritte, Cécile Apel, Marc LitaudonAbstract:One secobutanolide, two butanolides and six Drimane sesquiterpenoids were isolated from the bark and leaves of Zygogynum pancheri and Zygogynum acsmithii (Winteraceae) along with six known Drimanes, isodrimanial, 1beta-O-p-methoxy-E-cinnamoyl-bemadienolide, 7-ketoisodrimenin, drimenin, polygodial and 1beta-E-cinnamoyl-6alpha-hydroxypolygodial. Their structures were elucidated through analysis of spectroscopic data. Drimane sesquiterpenoids with a dialdehyde function exhibited significant inhibitory activities in the in vitro cytotoxic assays against KB, HL60 and HCT116 cancer cell lines.
Franz Hadacek - One of the best experts on this subject based on the ideXlab platform.
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antimicrobial Drimane sesquiterpenes contribute to balanced antagonism but do not structure bacterial and fungal endophytes in the african pepper bark tree warburgia ugandensis
Frontiers in Ecology and Evolution, 2017Co-Authors: Sigrid Drage, Doris Engelmeier, Markus Gorfer, Alice Muchugi, Vladimir Chobot, Angela Sessitsch, Birgit Mitter, Ramni Jamnadass, Franz HadacekAbstract:The African pepper bark tree, Warburgia ugandensis, accumulates antimicrobial Drimane sesquiterpenes in all of its organs. One hypothesis states that plant defense compounds determine endophyte community structure. Another hypothesis suggests that they just facilitate the endophytic lifestyle by exerting a balanced antagonism. To explore this, a representative selection of endophytic bacterial and fungal isolates from this tree species was assayed together with six non-endophytic strains to determine their tolerance and susceptibility to the root and leaf extract fraction containing high and low Drimane sesquiterpene amounts respectively. Inhibitory effects were explored by assessing both growth and growth efficiency, the latter of which relates respiratory activity to growth. The susceptibility of the tested strains showed considerable variation and the obtained patterns did not allow a clear distinction between root and leaf endophytes as well as endophytes and non-endophytes. In addition, all strains were also assayed against juglone, an antimicrobial and redox-active aromatic naphthoquinone. A comparison of differential pulse voltammograms and efficacy in variants of the deoxyribose degradation assay revealed that Drimane sesquiterpenes possess anti- and pro-oxidant activities that compare to those of juglone. Leaf endophytes showed higher resistance to oxidative stress than root endophytes, quite contrary to the actual exposure. The obtained results support the notion that structural diverse plant defense compounds can contribute to a balanced antagonism against but not to structuring of endophyte communities. Oxidative stress seems to be involved in generating this effect albeit it cannot explain it alone.
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antimicrobial Drimane sesquiterpenes and their effect on endophyte communities in the medical tree warburgia ugandensis
Frontiers in Microbiology, 2014Co-Authors: Sigrid Drage, Alice Muchugi, Angela Sessitsch, Birgit Mitter, Ramni Jamnadass, Franz HadacekAbstract:Metabolite profiles (GC–MS), Drimane sesquiterpenes, sugars and sugar alcohols, were compared with bacterial and fungal endophyte communities (T-RFLP, DNA clones, qPCR) in leaves and roots of the pepper bark tree, Warburgia ugandensis (Canellaceae). Ten individuals each were assessed from two locations east and west of the Great Rift Valley, Kenya, Africa, which differed in humidity and vegetation, closed forest versus open savannah. Despite organ- and partially site-specific variation of Drimane sesquiterpenes, no clear effects on bacterial and fungal endophyte communities could be detected. The former were dominated by gram-negative Gammaproteobacteria, Pseudomonadaceae and Enterobacteriaceae, as well as gram-positive Firmicutes; the fungal endophyte communities were more diverse but no specific groups dominated. Despite initial expectations, the endophyte community of the pepper bark tree did not differ from other trees that much.
Marc Litaudon - One of the best experts on this subject based on the ideXlab platform.
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Drimane derivatives as the first examples of covalent BH3-mimetics that target MCL-1.
ChemMedChem, 2021Co-Authors: Florian Daressy, Vincent Dumontet, Marc Litaudon, Cécile Apel, Florian Malard, Line Seguy, Vincent Guérineau, Aude Robert, Anne-claire Groo, Jérôme BignonAbstract:Drimane sesquiterpenoid dialdehydes are natural compounds with antiproliferative properties. Nevertheless, their mode of action has not yet been discovered. In this publication, we have demonstrated that various Drimanes are potent inhibitors of MCL-1 and BCL-xL, two proteins of the BCL-2 family that are overexpressed in various cancers, including lymphoid malignancies. Subtle changes in their structure significantly modified their activity on the target proteins. The two most active compounds are MCL-1 selective and bind in the BH3 binding groove of the protein. Complementary studies, by NMR and mass spectrometry analyses but also synthesis showed that they are covalent inhibitors of MCL-1, via the formation of a pyrrole adduct. In addition, cytotoxic assays revealed that these two compounds show a cytotoxic selectivity for BL2, a MCL-1/BCL-xL dependent cell line and induce apoptosis.
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ugandenial a a new Drimane type sesquiterpenoid from warburgia ugandensis
Molecules, 2009Co-Authors: Min Xu, Bernard Turyagenda Kiremire, John M Kasenene, Sabrina Krief, Marietherese Martin, Vincent Dumontet, Marc Litaudon, Françoise GuéritteAbstract:One new Drimane-type sesquiterpenoid, named ugandenial A ( 1), was isolated from the ethyl acetate extract of the bark of Warburgia ugandensis (Canellaceae) together with eight known Drimane-type sesquiterpenoids: 11 alpha-hydroxycinnamosmolide ( 2), warburganal ( 3), polygodial ( 4), mukaadial ( 5), dendocarbin A ( 6), 9 alpha-hydroxycinnamolide ( 7), dendocarbin L ( 8) and dendocarbin M ( 9). Their structures were established by detailed spectroscopic analysis. In addition a keto-enol equilibrium was demonstrated for compound 1 through a detailed NMR analysis run in CD(2)Cl(2) at 190 K. Cytotoxicity of the isolated compounds against KB cells was evaluated.
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Cytotoxic sesquiterpenoids from Winteraceae of Caledonian rainforest.
Phytochemistry, 2009Co-Authors: Noureddine Allouche, Marietherese Martin, Vincent Dumontet, Françoise Guéritte, Cécile Apel, Marc LitaudonAbstract:One secobutanolide, two butanolides and six Drimane sesquiterpenoids were isolated from the bark and leaves of Zygogynum pancheri and Zygogynum acsmithii (Winteraceae) along with six known Drimanes, isodrimanial, 1beta-O-p-methoxy-E-cinnamoyl-bemadienolide, 7-ketoisodrimenin, drimenin, polygodial and 1beta-E-cinnamoyl-6alpha-hydroxypolygodial. Their structures were elucidated through analysis of spectroscopic data. Drimane sesquiterpenoids with a dialdehyde function exhibited significant inhibitory activities in the in vitro cytotoxic assays against KB, HL60 and HCT116 cancer cell lines.
Tsutomu Hoshino - One of the best experts on this subject based on the ideXlab platform.
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chemo enzymatic syntheses of Drimane type sesquiterpenes and the fundamental core of hongoquercin meroterpenoid by recombinant squalene hopene cyclase
Organic and Biomolecular Chemistry, 2012Co-Authors: Yukie Yonemura, Takuro Ohyama, Tsutomu HoshinoAbstract:Squalene–hopene cyclase (SHC) converts squalene (C30) into pentacyclic triterpenes of hopene and hopanol. A linear sesquiterpene, (6E,10E)-2,6,10-trimethyldodeca-2,6,10-triene, underwent cyclization catalyzed by SHC, affording the following six bicyclic sesquiterpenes (Drimane skeleton) in relatively high yield (68%): drim-7(8)-ene, drim-8(12)-ene, drim-8(9)-ene, driman-8α-ol, driman-8β-ol, and the novel sesquiterpene, named quasiclerodane, the skeleton of which is analogous to that of clerodane diterpene. To extend the scope of the enzymatic syntheses, acyclic sesquiterpenes to which a phenol moiety was appended were subjected to the enzymatic reaction catalyzed by SHC. The cyclic meroterpene core present in hongoquercins A and B was successfully prepared. The formation mechanisms of Drimane-type sesquiterpenes and the cyclic meroterpene core of hongoquercins A and B are discussed.
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Chemo-enzymatic syntheses of Drimane-type sesquiterpenes and the fundamental core of hongoquercin meroterpenoid by recombinant squalene–hopene cyclase
Organic & biomolecular chemistry, 2011Co-Authors: Yukie Yonemura, Takuro Ohyama, Tsutomu HoshinoAbstract:Squalene–hopene cyclase (SHC) converts squalene (C30) into pentacyclic triterpenes of hopene and hopanol. A linear sesquiterpene, (6E,10E)-2,6,10-trimethyldodeca-2,6,10-triene, underwent cyclization catalyzed by SHC, affording the following six bicyclic sesquiterpenes (Drimane skeleton) in relatively high yield (68%): drim-7(8)-ene, drim-8(12)-ene, drim-8(9)-ene, driman-8α-ol, driman-8β-ol, and the novel sesquiterpene, named quasiclerodane, the skeleton of which is analogous to that of clerodane diterpene. To extend the scope of the enzymatic syntheses, acyclic sesquiterpenes to which a phenol moiety was appended were subjected to the enzymatic reaction catalyzed by SHC. The cyclic meroterpene core present in hongoquercins A and B was successfully prepared. The formation mechanisms of Drimane-type sesquiterpenes and the cyclic meroterpene core of hongoquercins A and B are discussed.
Vincent Dumontet - One of the best experts on this subject based on the ideXlab platform.
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Drimane derivatives as the first examples of covalent BH3-mimetics that target MCL-1.
ChemMedChem, 2021Co-Authors: Florian Daressy, Vincent Dumontet, Marc Litaudon, Cécile Apel, Florian Malard, Line Seguy, Vincent Guérineau, Aude Robert, Anne-claire Groo, Jérôme BignonAbstract:Drimane sesquiterpenoid dialdehydes are natural compounds with antiproliferative properties. Nevertheless, their mode of action has not yet been discovered. In this publication, we have demonstrated that various Drimanes are potent inhibitors of MCL-1 and BCL-xL, two proteins of the BCL-2 family that are overexpressed in various cancers, including lymphoid malignancies. Subtle changes in their structure significantly modified their activity on the target proteins. The two most active compounds are MCL-1 selective and bind in the BH3 binding groove of the protein. Complementary studies, by NMR and mass spectrometry analyses but also synthesis showed that they are covalent inhibitors of MCL-1, via the formation of a pyrrole adduct. In addition, cytotoxic assays revealed that these two compounds show a cytotoxic selectivity for BL2, a MCL-1/BCL-xL dependent cell line and induce apoptosis.
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ugandenial a a new Drimane type sesquiterpenoid from warburgia ugandensis
Molecules, 2009Co-Authors: Min Xu, Bernard Turyagenda Kiremire, John M Kasenene, Sabrina Krief, Marietherese Martin, Vincent Dumontet, Marc Litaudon, Françoise GuéritteAbstract:One new Drimane-type sesquiterpenoid, named ugandenial A ( 1), was isolated from the ethyl acetate extract of the bark of Warburgia ugandensis (Canellaceae) together with eight known Drimane-type sesquiterpenoids: 11 alpha-hydroxycinnamosmolide ( 2), warburganal ( 3), polygodial ( 4), mukaadial ( 5), dendocarbin A ( 6), 9 alpha-hydroxycinnamolide ( 7), dendocarbin L ( 8) and dendocarbin M ( 9). Their structures were established by detailed spectroscopic analysis. In addition a keto-enol equilibrium was demonstrated for compound 1 through a detailed NMR analysis run in CD(2)Cl(2) at 190 K. Cytotoxicity of the isolated compounds against KB cells was evaluated.
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Cytotoxic sesquiterpenoids from Winteraceae of Caledonian rainforest.
Phytochemistry, 2009Co-Authors: Noureddine Allouche, Marietherese Martin, Vincent Dumontet, Françoise Guéritte, Cécile Apel, Marc LitaudonAbstract:One secobutanolide, two butanolides and six Drimane sesquiterpenoids were isolated from the bark and leaves of Zygogynum pancheri and Zygogynum acsmithii (Winteraceae) along with six known Drimanes, isodrimanial, 1beta-O-p-methoxy-E-cinnamoyl-bemadienolide, 7-ketoisodrimenin, drimenin, polygodial and 1beta-E-cinnamoyl-6alpha-hydroxypolygodial. Their structures were elucidated through analysis of spectroscopic data. Drimane sesquiterpenoids with a dialdehyde function exhibited significant inhibitory activities in the in vitro cytotoxic assays against KB, HL60 and HCT116 cancer cell lines.
