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Wolfgang Barz - One of the best experts on this subject based on the ideXlab platform.
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Constitutive and elicitation induced metabolism of isoflavones and Pterocarpans in chickpea (Cicer arietinum) cell suspension cultures
Plant Cell Tissue and Organ Culture, 1994Co-Authors: Wolfgang Barz, Ulrike MackenbrockAbstract:Constitutive phenolics of chickpea cell suspension cultures are the isoflavones formononetin and biochanin A, the isoflavanones homoferreirin and cicerin and the Pterocarpans medicarpin and maackiain. They accumulate as vacuolar malonylglucosides. The biosynthetic pathways to isoflavones, Pterocarpans and malonylglucoside conjugates together with their enzymes are explained. Elicitation of cell cultures leads to pronounced increases in the activities of biosynthetic enzymes with differential effects on the enzymes involved in conjugate metabolism. Low elicitor doses favour Pterocarpan conjugate formation whereas high doses lead to Pterocarpan aglycone accumulation accompanied by vacuolar efflux of formononetin and Pterocarpan malonylglucosides. Elicitor-induced changes in enzyme activities and vacuolar efflux of conjugates are prevented by application of 10-3M concentrations of cinnamic acid. Cinnamate is alternatively metabolized to a glucose ester, a S-glutathionyl conjugate and to cell wall bounds forms; these reactions are intensified by elicitation. Isoflavone and Pterocarpan biosynthesis and conjugate metabolism as regulated by elicitation and cinnamate is depicted in a metabolic grid to explain the complex regulatory pattern of phenolic accumulation in chickpea cell cultures.
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elicitor induced formation of Pterocarpan phytoalexins in chickpea cicer arietinum l cell suspension cultures from constitutive isoflavone conjugates upon inhibition of phenylalanine ammonia lyase
Zeitschrift für Naturforschung C, 1991Co-Authors: Ulrike Mackenbrock, Wolfgang BarzAbstract:Regulatory pattern of constitutive isoflowone conjugate turnover and elicitor-caused Pterocarpan biosynthesis in chikpea cell suspension cultures. Using a specific PAL inhibitor in combination with feeding experiments we tried to demonstrate whether the formation of Pterocarpans will always proceed de novo or whether the demand for isoflavane intermediate may not be covered from the constitutive pool of the formononetin malonylglucoside
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elicitor induction of cytochrome p 450 monooxygenases in cell suspension cultures of chickpea cicer arietinum l and their involvement in Pterocarpan phytoalexin biosynthesis
Zeitschrift für Naturforschung C, 1991Co-Authors: W Gunia, Walter Hinderer, Uta Wittkampf, Wolfgang BarzAbstract:A yeast glucan elicitor causes the accumulation of the Pterocarpan phytoalexins medicarpin and maackiain in chickpea (Cicer arietinum) cell suspension cultures established from seeds. A cell culture line from a chickpea cultivar resistant against its main fungal pathogen Ascochyta rabiei accumulates large amounts (944 nm ol/g fr. wt.) whereas a cell culture line from a susceptible cultivar accumulates only low amounts (38 nm ol/g fr. wt.) of the phytoalexins. This is consistent with differential accumulation of Pterocarpan phytoalexins in intact plants [1], The first reactions in the Pterocarpan-specific branch of biosynthesis are hydroxylation of the isoflavone intermediate form ononetin in position 2′ or 3′, catalyzed by microsomal cytochrome P-450 monooxygenases. Upon elicitation form ononetin 2′-hydroxylase undergoes a strong transient induction in the cell suspension culture of the resistant cultivar, whereas in the cell culture from the susceptible cultivar it is only slightly induced. In both cell suspension cultures the induction of cinnamic acid 4-hydroxylase and of form ononetin 3′-hydroxylase does not show a clear correlation with phytoalexin accumulation. Experiments with different elicitor concentrations confirm that formononetin 2′-hydroxylase is much more induced in cell cultures from the resistant cultivar than from the susceptible one. It is concluded that the massive difference in phytoalexin accumulation between cell suspension cultures from the resistant and susceptible cultivar is determined mainly by the differential induction of form ononetin 2′-hydroxylase activity.
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elicitor induced metabolic changes in cell cultures of chickpea cicer arietinum l cultivars resistant and susceptible to ascochyta rabiei i investigations of enzyme activities involved in isoflavone and Pterocarpan phytoalexin biosynthesis
Planta, 1990Co-Authors: Susanne Daniel, Karin Tiemann, Uta Wittkampf, Wolfang Bless, Walter Hinderer, Wolfgang BarzAbstract:Cell-suspension cultures of Ascochyta rabiei-resistant (ILC 3279) and -susceptible (ILC 1929) chickpea (Cicer arietinum L.) cultivars were compared with regard to their elicitor-induced accumulation of Pterocarpan phytoalexins and increases in the activities of biosynthetic enzymes. The growth performances and protein patterns of the two cell-culture lines were essentially identical. Treatment of cell cultures with a polysaccharide elicitor from A. rabiei induced fivefold-higher amounts of the phytoalexins medicarpin and maackiain in the cells of the resistant than in the susceptible cultivar. Glucose 6-phosphate dehydrogenase and eight enzymes representing the general phenylpropanoid pathway, the flavonoid-forming steps and the Pterocarpanspecific branch of phytoalexin biosynthesis were found to be elicitor-induced. Phenylalanine ammonia-lyase and chalcone synthase reached sharp, transient optima some 8 h after elicitor application in the cells of both cultivars. The activities of isoflavone 2′- and 3′-hydroxylases were only induced in cells of the resistant cultivar with a maximum after 8 h. Cinnamic acid 4-hydroxylase, chalcone isomerase, 2′-hydroxyisoflavone reductase and Pterocarpan synthase showed a later or no sharp optimum. The isoflavone-specific 7-O-glucosyltransferase was not induced in either cell-culture line. Cells of the susceptible cultivar failed to induce significant activities of isoflavone 2′-hydroxylase and these cells produced only very low amounts of phytoalexins. Isoflavone 2′-hydroxylase is postulated to be the main limiting enzyme for Pterocarpan biosynthesis in cells of the susceptible cultivar. The Pterocarpan biosynthetic pathway in chickpea cells represents a suitable model for investigations of differential gene activation in connection with the expression of antimicrobial defence reactions.
Shital K Chattopadhyay - One of the best experts on this subject based on the ideXlab platform.
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the coumarin Pterocarpan conjugate a natural product inspired hybrid molecular probe for dna recognition
Organic and Biomolecular Chemistry, 2014Co-Authors: Shital K Chattopadhyay, Indranil Kundu, Ratnava MaitraAbstract:Thermally induced cascade sigmatropic rearrangement of a butynyloxycoumarin derivative has led to a quick access to the coumarin–Pterocarpan hybrid molecule. Biophysical studies together with molecular modeling show that this nature-inspired hybrid molecule is capable of binding to the minor groove of DNA as a non-conventional entity.
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acridone Pterocarpan conjugate a hybrid molecular probe for recognition of nucleic acids
ChemInform, 2014Co-Authors: Shital K Chattopadhyay, Ratnava Maitra, Indranil Kundu, Manoranjan Jana, Sushil Kumar Mandal, Anisur Rahman KhudabukhshAbstract:Molecules containing acridone and Pterocarpan structural subunits are synthesized and their capability of binding duplex DNA is demonstrated.
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Acridone—Pterocarpan Conjugate: A Hybrid Molecular Probe for Recognition of Nucleic Acids.
ChemInform, 2014Co-Authors: Shital K Chattopadhyay, Ratnava Maitra, Indranil Kundu, Manoranjan Jana, Sushil Kumar Mandal, Anisur Rahman Khuda-bukhshAbstract:Molecules containing acridone and Pterocarpan structural subunits are synthesized and their capability of binding duplex DNA is demonstrated.
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regio and stereoselective synthesis of Pterocarpan derivatives on a carbazole scaffold by cascade sigmatropic rearrangements
Synlett, 2006Co-Authors: Shital K Chattopadhyay, Debalina Ghosh, Titas BiswasAbstract:Thermal rearrangement of 1 -aryloxy-4-carbazolyloxy-but-2-ynes, regio- and stereoselectively led to the formation ofbenzofuropyranocarbazoles in a single step in good yields. An investigation into the mechanism of the formation of these heteroannulated Pterocarpan derivatives led to the serendipitous formation of isomeric benzofurofurocarbazole ring system.
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Regio- and Stereoselective Synthesis of Pterocarpan Derivatives on a Carbazole Scaffold by Cascade Sigmatropic Rearrangements
Synlett, 2006Co-Authors: Shital K Chattopadhyay, Debalina Ghosh, Titas BiswasAbstract:Thermal rearrangement of 1 -aryloxy-4-carbazolyloxy-but-2-ynes, regio- and stereoselectively led to the formation ofbenzofuropyranocarbazoles in a single step in good yields. An investigation into the mechanism of the formation of these heteroannulated Pterocarpan derivatives led to the serendipitous formation of isomeric benzofurofurocarbazole ring system.
Daneel Ferreira - One of the best experts on this subject based on the ideXlab platform.
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synthesis of isoflavonoids enantiopure cis and trans 6a hydroxyPterocarpans and a racemic trans Pterocarpan
Tetrahedron, 2001Co-Authors: Theunis G Van Aardt, Hendrik Van Rensburg, Daneel FerreiraAbstract:Abstract Aldol condensation between phenylacetates and benzaldehydes affords 2,3-diaryl-3-hydroxypropanoates which serve as common precursors to both the first racemic trans-Pterocarpan and enantiopure cis- and trans-6a-hydroxyPterocarpans.
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The first direct synthesis of Pterocarpans via aldol condensation of phenylacetates with benzaldehydes
Tetrahedron, 1998Co-Authors: Theunis G Van Aardt, Hendrik Van Rensburg, Daneel FerreiraAbstract:Abstract Aldol condensation between phenylacetates and benzaldehydes affords 2,3-diaryl-3-hydroxy-propanoates which are converted into Pterocarpans in moderate to high yields.
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Oligomeric isoflavonoids. Part 3. Daljanelins A–D, the first Pterocarpan- and isoflavanoid-neoflavonoid analogues
Journal of The Chemical Society-perkin Transactions 1, 1995Co-Authors: J. Albert Ferreira, Barend C B Bezuidenhoudt, E. Vincent Brandt, Daneel FerreiraAbstract:The structures of daljanelins A–C 1, 3 and 5, the first Pterocarpan-neoflavonoid oligomers, and of daljanelin D 6 a related isoflavonoid-neoflavonoid analogue from Dalbergia nitidula were established by spectroscopic methods. The structure and stereochemistry of daljanelin C 5 were unambiguously confirmed by synthesis via introduction of an electrophilic C-1 fragment to a Pterocarpan nucleus followed by anionic coupling of a C6·C2 precursor and the late introduction of the final C6 fragment by a Grignard reaction.
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oligomeric isoflavonoids part 3 daljanelins a d the first Pterocarpan and isoflavanoid neoflavonoid analogues
Journal of The Chemical Society-perkin Transactions 1, 1995Co-Authors: Albert J Ferreira, Vincent E Brandt, Barend C B Bezuidenhoudt, Daneel FerreiraAbstract:The structures of daljanelins A–C 1, 3 and 5, the first Pterocarpan-neoflavonoid oligomers, and of daljanelin D 6 a related isoflavonoid-neoflavonoid analogue from Dalbergia nitidula were established by spectroscopic methods. The structure and stereochemistry of daljanelin C 5 were unambiguously confirmed by synthesis via introduction of an electrophilic C-1 fragment to a Pterocarpan nucleus followed by anionic coupling of a C6·C2 precursor and the late introduction of the final C6 fragment by a Grignard reaction.
Jeong An Park - One of the best experts on this subject based on the ideXlab platform.
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A new Pterocarpan, (-)-maackiain sulfate, from the roots ofSophora subprostrata
Archives of Pharmacal Research, 2003Co-Authors: Jeong An ParkAbstract:A new Pterocarpan, (-)-maackiain 3-sulfate ( 1 ) was isolated from the methanol extract of roots of Sophora subprostarata together with (-)-maackiain ( 2 ), trifolirhizin ( 3 ), lupeol ( 4 ), ononin ( 5 ), 7,4′-dihydroxyflavone ( 6 ), and (+)-syringaresinol ( 7 ). The structure of 1 was determined by analyses of 2D NMR and HRFABMS. Compounds 5–7 were isolated from this plant for the first time.
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a new Pterocarpan maackiain sulfate from the roots of sophora subprostrata
Archives of Pharmacal Research, 2003Co-Authors: Jeong An ParkAbstract:A new Pterocarpan, (-)-maackiain 3-sulfate (1) was isolated from the methanol extract of roots of Sophora subprostarata together with (-)-maackiain (2), trifolirhizin (3), lupeol (4), ononin (5), 7,4′-dihydroxyflavone (6), and (+)-syringaresinol (7). The structure of1 was determined by analyses of 2D NMR and HRFABMS. Compounds5–7 were isolated from this plant for the first time.
Ignacio Rodríguez-garcía - One of the best experts on this subject based on the ideXlab platform.
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Synthesis of Pterocarpans.
Natural Product Communications, 2020Co-Authors: Leticia Jiménez-gonzález, Miriam Álvarez-corral, Manuel Muñoz-dorado, Carmen Hernández-cervantes, Ignacio Rodríguez-garcíaAbstract:The total synthesis of natural Pterocarpans and analogs is reviewed.
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Pterocarpans: interesting natural products with antifungal activity and other biological properties
Phytochemistry Reviews, 2008Co-Authors: Leticia Jiménez-gonzález, Miriam Álvarez-corral, Manuel Muñoz-dorado, Ignacio Rodríguez-garcíaAbstract:Among the phytoalexins with the highest antifungal activity is the isoflavonoid based group of Pterocarpans. Here, we present a comprehensive inventory of the structures and sources of Pterocarpans, and summarize some of their most interesting biological activities.
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A concise and diastereoselective total synthesis of cis and trans-Pterocarpans
Chemical Communications, 2005Co-Authors: Leticia Jiménez-gonzález, Miriam Álvarez-corral, Manuel Muñoz-dorado, Ignacio Rodríguez-garcíaAbstract:A new strategy for the diastereoselective and convergent synthesis of Pterocarpans which is able to control the relative stereochemistry of the molecule through allylation of aromatic aldehydes with cyclic allylsiloxanes is described.
