The Experts below are selected from a list of 237 Experts worldwide ranked by ideXlab platform
Indra Prakash - One of the best experts on this subject based on the ideXlab platform.
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Complete Structure Elucidation of New Steviol Glycosides Possessing 9 Glucose Units Isolated from Stevia rebaudiana
Natural Product Communications, 2020Co-Authors: Indra Prakash, Cynthia Bunders, Romila D Charan, Catherine Ramirez, Sangphyo Hong, Gil Ma, Krishna Prasad Devkota, Tara M SnyderAbstract:In our continued effort to discover new Diterpene Glycoside sweeteners from Stevia rebaudiana Bertoni with a better taste profile than that of rebaudioside M, we have isolated three novel steviol g...
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a novel Diterpene Glycoside with nine glucose units from stevia rebaudiana bertoni
Biomolecules, 2017Co-Authors: Indra Prakash, Cynthia Bunders, Romila D Charan, Catherine Ramirez, Krishna P Devkota, Tara M SnyderAbstract:Following our interest in new Diterpene Glycosides with better taste profiles than that of Rebaudioside M, we have recently isolated and characterized Rebaudioside IX—a novel steviol Glycoside—from a commercially‐supplied extract of Stevia rebaudiana Bertoni. This molecule contains a hexasaccharide group attached at C‐13 of the central Diterpene core, and contains three additional glucose units when compared with Rebaudioside M. Here we report the complete structure elucidation—based on extensive Nuclear Magnetic Resonance (NMR) analysis (1H, 13C, Correlation Spectroscopy (COSY), Heteronuclear Single Quantum Coherence‐Distortionless Enhancement Polarization Transfer (HSQC‐DEPT), Heteronuclear Multiple Bond Correlation (HMBC), 1D Total Correlation Spectroscopy (TOCSY), Nuclear Overhauser Effect Spectroscopy (NOESY)) and mass spectral data—of this novel Diterpene Glycoside with nine sugar moieties and containing a relatively rare 16 α‐linked Glycoside. A steviol Glycoside bearing nine glucose units is unprecedented in the literature, and could have an impact on the natural sweetener catalog.
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a new Diterpene Glycoside 15α hydroxy rebaudioside m isolated from stevia rebaudiana
Natural Product Communications, 2015Co-Authors: Indra Prakash, Cynthia Bunders, Romila D Charan, Catherine Ramirez, Tara M Snyder, Krishna Prasad Devkota, Christopher PriedemannAbstract:: In a continued search for novel diterpenoid Glycosides, we recently isolated and characterized a Rebaudioside M derivative with a hydroxyl group at position 15 in the central Diterpene core from an extract of Stevia rebaudiana Bertoni. Here we report the complete structure elucidation of 15α-hydroxy-Rebaudioside M (2) on the basis of NMR (1H, 13C, COSY, HSQC-DEPT, HMBC, 1D TOCSY, NOESY) and mass spectral data. Steviol Glycoside with a hydroxyl group at C-15 in the central Diterpene core has not been previously reported.
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structural characterization of the degradation products of a minor natural sweet Diterpene Glycoside rebaudioside m under acidic conditions
International Journal of Molecular Sciences, 2014Co-Authors: Indra Prakash, Venkata Sai Prakash Chaturvedula, Avetik MarkosyanAbstract:Degradation of rebaudioside M, a minor sweet component of Stevia rebaudiana Bertoni, under conditions that simulated extreme pH and temperature conditions has been studied. Thus, rebaudioside M was treated with 0.1 M phosphoric acid solution (pH 2.0) and 80 °C temperature for 24 h. Experimental results indicated that rebaudioside M under low pH and higher temperature yielded three minor degradation compounds, whose structural characterization was performed on the basis of 1D (1H-, 13C-) & 2D (COSY, HSQC, HMBC) NMR, HRMS, MS/MS spectral data as well as enzymatic and acid hydrolysis studies.
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a new Diterpene Glycoside from stevia rebaudiana
Molecules, 2011Co-Authors: Venkata Sai Prakash Chaturvedula, Indra PrakashAbstract:From the commercial extract of the leaves of Stevia rebaudiana, a new Diterpene Glycoside was isolated besides the known steviol Glycosides including stevioside, rebaudiosides A-F, rubusoside and dulcoside A. The new compound was identified as 13-[(2-O-β-D-glucopyranosyl-3-O-β-D-glucopyranosyl-β-D-glucopyranosyl)oxy] ent-kaur-16-en-19-oic acid-(2-O-α-L-rhamnopyranosyl-β-D-glucopyranosyl) ester (1) on the basis of extensive spectroscopic (NMR and MS) and chemical studies.
Venkata Sai Prakash Chaturvedula - One of the best experts on this subject based on the ideXlab platform.
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isolation and structure elucidation of a new Diterpene Glycoside from stevia rebaudiana bertoni
Journal of Field Robotics, 2018Co-Authors: Venkata Sai Prakash Chaturvedula, Srinivasa Rao MeneniAbstract:A new minor Diterpene Glycoside has been isolated from a commercial extract of the leaves of Stevia rebaudiana and its structure was identified as 13-[(2- O -β-D-glucopyranosyl-β-D-glucopyranosyl)oxy] ent -kaur-16-en-19-oic acid-[2- O -(2- O -β-D-glucopyranosyl)-β-D-glucopyranosyl-3- O -b-D-glucopyranosyl-β-D-glucopyranosyl] ester ( 1 ) based on extensive NMR (1D and 2D) and mass spectroscopic data, and hydrolysis studies.
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isolation and structural characterization of a new minor Diterpene Glycoside from stevia rebaudiana
Natural Product Communications, 2014Co-Authors: Venkata Sai Prakash Chaturvedula, Julian ZamoraAbstract:: From the commercial extract of the leaves of the sweet plant Stevia rebaudiana Bertoni obtained from Sinochem Qingdao Co. Ltd., a new Diterpene Glycoside having three β-D-glucopyranosyl units of which two of them were connected in a relatively rare linkage of 3-β-D-glucobiosyl substitution at C-19 position of the aglycone steviol. The structure of the new compound has been characterized as 13-β-D-glucopyranosyloxy ent-kaur-16-en-19-oic acid-[(3-O-β-D- glucopyranosyl-β-D-glucopyranosyl) ester (1) on the basis of extensive 1D (1H and 13C) and 2D NMR (TOCSY, HMQC, and HMBC), and High Resolution mass spectroscopic data as well as hydrolysis studies.
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structural characterization of the degradation products of a minor natural sweet Diterpene Glycoside rebaudioside m under acidic conditions
International Journal of Molecular Sciences, 2014Co-Authors: Indra Prakash, Venkata Sai Prakash Chaturvedula, Avetik MarkosyanAbstract:Degradation of rebaudioside M, a minor sweet component of Stevia rebaudiana Bertoni, under conditions that simulated extreme pH and temperature conditions has been studied. Thus, rebaudioside M was treated with 0.1 M phosphoric acid solution (pH 2.0) and 80 °C temperature for 24 h. Experimental results indicated that rebaudioside M under low pH and higher temperature yielded three minor degradation compounds, whose structural characterization was performed on the basis of 1D (1H-, 13C-) & 2D (COSY, HSQC, HMBC) NMR, HRMS, MS/MS spectral data as well as enzymatic and acid hydrolysis studies.
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isolation nmr spectral analysis and hydrolysis studies of a hepta pyranosyl Diterpene Glycoside from stevia rebaudiana bertoni
Biomolecules, 2013Co-Authors: Venkata Sai Prakash Chaturvedula, Steven Chen, Oliver YuAbstract:From the commercial extract of the leaves of Stevia rebaudiana Bertoni, a minor steviol Glycoside, 13-[(2-O-β-d-glucopyranosyl-3-O-β-d-glucopyranosyl-β-d-glucopyranosyl)oxy] ent-kaur-16-en-19-oic acid-[(2-O-(3-O-β-d-glucopyranosyl-α-l-rhamnopyranosyl)-3-O-β-d-glucopyranosyl-β-d-glucopyranosyl) ester] (1); also known as rebaudioside O having seven sugar units has been isolated. Its structural characterization has been achieved by the extensive 1D (1H and 13C), and 2D NMR (COSY, HMQC, HMBC) as well as mass spectral data. Further, hydrolysis studies were performed on rebaudioside O using acid and enzymatic methods to identify aglycone and sugar residues in its structure as well as their configurations.
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a new Diterpene Glycoside from stevia rebaudiana
Molecules, 2011Co-Authors: Venkata Sai Prakash Chaturvedula, Indra PrakashAbstract:From the commercial extract of the leaves of Stevia rebaudiana, a new Diterpene Glycoside was isolated besides the known steviol Glycosides including stevioside, rebaudiosides A-F, rubusoside and dulcoside A. The new compound was identified as 13-[(2-O-β-D-glucopyranosyl-3-O-β-D-glucopyranosyl-β-D-glucopyranosyl)oxy] ent-kaur-16-en-19-oic acid-(2-O-α-L-rhamnopyranosyl-β-D-glucopyranosyl) ester (1) on the basis of extensive spectroscopic (NMR and MS) and chemical studies.
Tara M Snyder - One of the best experts on this subject based on the ideXlab platform.
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Complete Structure Elucidation of New Steviol Glycosides Possessing 9 Glucose Units Isolated from Stevia rebaudiana
Natural Product Communications, 2020Co-Authors: Indra Prakash, Cynthia Bunders, Romila D Charan, Catherine Ramirez, Sangphyo Hong, Gil Ma, Krishna Prasad Devkota, Tara M SnyderAbstract:In our continued effort to discover new Diterpene Glycoside sweeteners from Stevia rebaudiana Bertoni with a better taste profile than that of rebaudioside M, we have isolated three novel steviol g...
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a novel Diterpene Glycoside with nine glucose units from stevia rebaudiana bertoni
Biomolecules, 2017Co-Authors: Indra Prakash, Cynthia Bunders, Romila D Charan, Catherine Ramirez, Krishna P Devkota, Tara M SnyderAbstract:Following our interest in new Diterpene Glycosides with better taste profiles than that of Rebaudioside M, we have recently isolated and characterized Rebaudioside IX—a novel steviol Glycoside—from a commercially‐supplied extract of Stevia rebaudiana Bertoni. This molecule contains a hexasaccharide group attached at C‐13 of the central Diterpene core, and contains three additional glucose units when compared with Rebaudioside M. Here we report the complete structure elucidation—based on extensive Nuclear Magnetic Resonance (NMR) analysis (1H, 13C, Correlation Spectroscopy (COSY), Heteronuclear Single Quantum Coherence‐Distortionless Enhancement Polarization Transfer (HSQC‐DEPT), Heteronuclear Multiple Bond Correlation (HMBC), 1D Total Correlation Spectroscopy (TOCSY), Nuclear Overhauser Effect Spectroscopy (NOESY)) and mass spectral data—of this novel Diterpene Glycoside with nine sugar moieties and containing a relatively rare 16 α‐linked Glycoside. A steviol Glycoside bearing nine glucose units is unprecedented in the literature, and could have an impact on the natural sweetener catalog.
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a new Diterpene Glycoside 15α hydroxy rebaudioside m isolated from stevia rebaudiana
Natural Product Communications, 2015Co-Authors: Indra Prakash, Cynthia Bunders, Romila D Charan, Catherine Ramirez, Tara M Snyder, Krishna Prasad Devkota, Christopher PriedemannAbstract:: In a continued search for novel diterpenoid Glycosides, we recently isolated and characterized a Rebaudioside M derivative with a hydroxyl group at position 15 in the central Diterpene core from an extract of Stevia rebaudiana Bertoni. Here we report the complete structure elucidation of 15α-hydroxy-Rebaudioside M (2) on the basis of NMR (1H, 13C, COSY, HSQC-DEPT, HMBC, 1D TOCSY, NOESY) and mass spectral data. Steviol Glycoside with a hydroxyl group at C-15 in the central Diterpene core has not been previously reported.
Douglas A Kinghorn - One of the best experts on this subject based on the ideXlab platform.
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cordifolide a a sulfur containing clerodane Diterpene Glycoside from tinospora cordifolia
Organic Letters, 2012Co-Authors: Cesar Terrazas, Claudio M Lezamadavila, Nirmala Rege, Judith C Gallucci, Abhay R Satoskar, Douglas A KinghornAbstract:Cordifolide A (1), a novel unprecedented sulfur-containing clerodane Diterpene Glycoside, together with other two new Diterpene Glycosides, cordifolides B (2) and C (3), and four known analogues, was isolated from a methanol-soluble extract of the stems of Tinospora cordifolia. The structures of the new compounds were determined on the basis of spectroscopic data interpretation, with that of cordifolide A (1) confirmed by a single-crystal X-ray crystallographic analysis. All isolates were evaluated for their in vitro immunomodulatory activity using mouse bone marrow-derived dentritic cells (BMDCs).
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gaudichaudiosides a e five novel Diterpene Glycoside constituents from the sweet tasting plant baccharis gaudichaudiana
Tetrahedron, 1991Co-Authors: Fekadu Fullas, Raouf A Hussain, Eugenia Bordas, John M Pezzuto, Djaja D Soejarto, Douglas A KinghornAbstract:A new potently sweet labdane Diterpene arabinoside, gaudichaudioside A (1), was isolated from the aerial parts of Baccharis gaudichaudiana DC. (Compositae). Also isolated were four other novel labdane arabinosides, gaudichaudiosides B–E (2–5), which although closely related to 1 structurally, were not found to be highly sweet.
Yoel Kashman - One of the best experts on this subject based on the ideXlab platform.
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lemnaflavoside a new Diterpene Glycoside from the soft coral lemnalia flava
Journal of Natural Products, 2002Co-Authors: Amira Rudi, Sharon Levi, Yehuda Benayahu, Yoel KashmanAbstract:Lemnaflavoside (1) and three monoacetates (2-4) have been isolated from the Indo-Pacific soft coral Lemnalia flava, collected off Mombasa, Kenya. The structure of the new Glycoside was elucidated by interpretation of MS and 2D NMR data. The sugar of the Diterpene Glycoside was found to be D-xylose.