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Hassan AA, Huang ML. Stereoselective synthesis of photoactivatable Man(β1,4)GlcNAc-based bioorthogonal probes. Tetrahedron Lett 2023; 122:154521. [PMID: 37274137 PMCID: PMC10237449 DOI: 10.1016/j.tetlet.2023.154521] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We report an operationally facile protocol to prepare photoactivatable probes of the bioactive mammalian disaccharide, Man(β1,4)GlcNAc. Using conformationally restricted mannosyl hemi-acetal donors in a one-pot chlorination, iodination and glycosylation sequence, β-mannosides were generated in excellent diastereoselectivities and yields. Upon accessing the disaccharide, we generated the corresponding photoactivatable probes by appending a diazirine-alkyne equipped linker via a condensation reaction between a diazirine-containing linker and C-1 and C-2 derivatized mannosylamines to furnish the desired C-1 and C-2 modified Man(β1,4)GlcNAc-based probes. This new synthetic protocol greatly simplifies the preparation of this important bioactive disaccharide to enable future work to identify its protein binding partners in cells.
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Affiliation(s)
- Abdullah A. Hassan
- Department of Molecular Medicine and Department of Chemistry, Scripps Research, 10550 N. Torrey Pines Rd., La Jolla, CA 92037
| | - Mia L. Huang
- Department of Molecular Medicine and Department of Chemistry, Scripps Research, 10550 N. Torrey Pines Rd., La Jolla, CA 92037
- Skaggs Graduate School of Chemical and Biological Sciences, Scripps Research, 10550 N. Torrey Pines Rd., La Jolla, CA 92037
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2
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Ackee (Blighia sapida K.D. Koenig) Leaves and Arils Methanolic Extracts Ameliorate CdCl2-Induced Oxidative Stress Biomarkers in Drosophila melanogaster. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2022; 2022:3235031. [DOI: 10.1155/2022/3235031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 09/19/2022] [Accepted: 10/15/2022] [Indexed: 11/15/2022]
Abstract
Different ethnomedical benefits have been documented on different parts of Ackee (Blighia sapida); however, their roles in ameliorating oxidative damages are not well established. CdCl2 inhibitory effects on some oxidative-stress biomarkers and ameliorative potentials of Ackee leaves (AL) and arils (AS) methanolic extracts were studied using Drosophila melanogaster as a model. One to 3-day-old D. melanogaster flies were orally exposed to different concentrations of CdCl2 in their diet for 7 days. The fly’s survival profile and negative geotaxis assays were subsequently analysed. Methanolic extracts of AL and AS treatments showed negative geotaxis behaviour, and extracts were able to ameliorate the effect of Cd2+ on catalase and GST activities and increase total thiol and GSH levels, while it reduced the H2O2 generation (
) when compared to the control. Furthermore, Cd2+ exhibited noncompetitive and uncompetitive enzyme inhibition on catalase and GST activities, respectively, which may have resulted in the formation of Enzyme-substrate-Cd2+ transition complexes, thus inhibiting the conversion of substrate to product. This study, thus, suggests that the Cd2+ mechanism of toxicity was associated with oxidative damage, as evidenced by the alteration in the oxidative stress-antioxidant imbalance, and that the AL and AS extracts possess essential phytochemicals that could alleviate possibly deleterious oxidative damage effects of environmental pollutants such as CdCl2. Thus, Ackee plant parts possess essential phytonutrients which could serve as valuable resources in heavy metal toxicity management.
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Moffi Biang AE, Messi LM, Le Doux Kamto E, Simo LM, Lavedan P, Vedrenne M, Mbing JN, Pegnyemb DE, Haddad M, Noté OP. Triterpenoid saponins and others glycosides from the stem barks of Pancovia turbinata Radlk. Carbohydr Res 2021; 508:108393. [PMID: 34273843 DOI: 10.1016/j.carres.2021.108393] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2021] [Revised: 06/20/2021] [Accepted: 06/30/2021] [Indexed: 10/20/2022]
Abstract
In our continuing search of saponins from the plant of Sapindaceae family, phytochemical investigation of the stem barks of Pancovia turbinata Radlk., led to the isolation and structural characterization of two new triterpenoid saponins, named turbinatosides A-B (1-2), one new farnesyl glycoside, named turbinoside A (3), one new coumarin glucoside, named panturboside A (4), together with a known saponin (5). The structures of the new compounds were established, using extensive analysis of NMR techniques, mainly 1D NMR (1H, 13C, and DEPT) and 2D NMR (COSY, NOESY, HSQC, HSQC-TOCSY and HMBC) experiments, HRESIMS and by comparison with the literature data, as 3-O-β-d-xylopyranosyl-(1 → 3)-α-l-arabinopyranosyl-(1 → 4)-β-d-glucopyranosyl-(1 → 3)-α-l-rhamnopyranosyl-(1 → 2)-α-l-arabinopyranosylhederagenin 28-O-β-d-glucopyranosyl ester (1), 3-O-α-l-arabinopyranosyl-(1 → 4)-β-d-glucopyranosyl-(1 → 3)-α-l-rhamnopyranosyl-(1 → 2)-α-l-arabinopyranosylhederagenin 28-O-β-d-xylopyranosyl-(1 → 4)-β-d-glucopyranosyl ester (2), 1-O-{β-d-glucopyranosyl-(1 → 3)-α-l-rhamnopyranosyl-(1 → 2)-[α-l-rhamnopyranosyl-(1 → 6)]-β-d-glucopyranosyl}-(2E,6E)-farnes-1,12-diol (3), and 5-O-β-d-glucopyranosyl-5,6,7-trihydroxy-8-methoxycoumarin (4), respectively. Our findings highlight the presence of -3Rha-2Ara-3hederagenin oligosaccharidic sequence usually described in saponins from Sapindoideae subfamily of Sapindaceae family, as well as farnesol glycosides, and represent therefore a valuable contribution to the chemotaxonomy of the Sapindoideae subfamily.
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Affiliation(s)
- Armand Emmanuel Moffi Biang
- Laboratoire de Pharmacochimie des Substances Naturelles, Département de Chimie Organique, Faculté de Sciences, Université de Yaoundé I, BP 812, Yaoundé, Cameroon; Institut de Recherches Médicales et D'études des Plantes Médicinales Du Cameroun (IMPM), B.P. 13033, Yaoundé, Cameroon
| | - Lin Marcellin Messi
- Laboratoire de Pharmacochimie des Substances Naturelles, Département de Chimie Organique, Faculté de Sciences, Université de Yaoundé I, BP 812, Yaoundé, Cameroon; Institut de Recherche Agricole pour le Développement (IRAD), BP 2067, Yaoundé, Cameroon; UMR 152 Pharma Dev, Université de Toulouse, IRD, UPS, France.
| | - Eutrophe Le Doux Kamto
- Laboratoire de Pharmacochimie des Substances Naturelles, Département de Chimie Organique, Faculté de Sciences, Université de Yaoundé I, BP 812, Yaoundé, Cameroon
| | - Line Made Simo
- Laboratoire de Pharmacochimie des Substances Naturelles, Département de Chimie Organique, Faculté de Sciences, Université de Yaoundé I, BP 812, Yaoundé, Cameroon
| | | | | | - Josephine Ngo Mbing
- Laboratoire de Pharmacochimie des Substances Naturelles, Département de Chimie Organique, Faculté de Sciences, Université de Yaoundé I, BP 812, Yaoundé, Cameroon
| | - Dieudonné Emmanuel Pegnyemb
- Laboratoire de Pharmacochimie des Substances Naturelles, Département de Chimie Organique, Faculté de Sciences, Université de Yaoundé I, BP 812, Yaoundé, Cameroon
| | - Mohamed Haddad
- UMR 152 Pharma Dev, Université de Toulouse, IRD, UPS, France
| | - Olivier Placide Noté
- Laboratoire de Pharmacochimie des Substances Naturelles, Département de Chimie Organique, Faculté de Sciences, Université de Yaoundé I, BP 812, Yaoundé, Cameroon; UMR 152 Pharma Dev, Université de Toulouse, IRD, UPS, France.
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Petit B, Mitaine-Offer AC, Fischer J, Schüffler A, Delaude C, Miyamoto T, Tanaka C, Thines E, Lacaille-Dubois MA. Anti-phytopathogen terpenoid glycosides from the root bark of Chytranthus macrobotrys and Radlkofera calodendron. PHYTOCHEMISTRY 2021; 188:112797. [PMID: 34023719 DOI: 10.1016/j.phytochem.2021.112797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 04/23/2021] [Accepted: 04/26/2021] [Indexed: 06/12/2023]
Abstract
Chytranthus macrobotrys and Radlkofera calodendron are two Sapindaceae characterized by a lack of phytochemical data. Both root barks from the two Sapindaceae species were processed by ethanol extraction followed by the isolation of their primary constituents by liquid chromatography. This process yielded four previously undescribed terpenoid glycosides together with eight known analogues. Extracts and isolated compounds from C. macrobotrys and R. calodendron were then screened for antimicrobial activity against fifteen phytopathogens. The biological screening also involved extracts and pure compounds from Blighia unijugata and Blighia welwitschii, two Sapindaceae previously studied by our group. Phytopathogens were chosen based on their economic impact on agriculture worldwide. The selection was composed primarily of fungal species including; Pyricularia oryzae, Gaeumannomyces graminis var. tritici, Zymoseptoria tritici, Fusarium oxysporum, Botrytis cinerea, Pythium spp., Trichoderma spp. and Rhizoctonia solani. Furthermore, pure terpenoid glycosides were tested for the first time against wood-inhabiting phytopathogens such as; Phaeomoniella chlamydospora, Phaeoacremonium minimum, Fomitiporia mediterranea, Eutype lata and Xylella fastidiosa. Raw extracts exhibited different levels of activity dependent on the organism. Some pure compounds, including 3-O-α-L-arabinopyranosyl-(1 → 4)-β-D-xylopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosylhederagenin, 3-O-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosylhederagenin (α-hederin), 3-O-β-D-glucopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosylhederagenin (macranthoside A) and 3-O-α-L-arabinopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosylhederagenin (clemontanoside C), exhibited significant growth inhibitions on Pyricularia oryzae, Gaeumannomyces graminis var. tritici, Fomitiporia mediterranea and Zymoseptoria tritici. Monodesmoside triterpene saponins, in particular, exhibited MIC (IC100) values as low as 25 μg/ml and IC50 values as low as 10 μg/ml against these phytopathogens. Structure-activity relationships, as well as plant-microbe interactions, were discussed.
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Affiliation(s)
- Bastien Petit
- PEPITE EA 4267, Laboratoire de Pharmacognosie, UFR des Sciences de Santé, Université de Bourgogne Franche-Comté, BP 87900, 21079, Dijon, Cedex, France
| | - Anne-Claire Mitaine-Offer
- PEPITE EA 4267, Laboratoire de Pharmacognosie, UFR des Sciences de Santé, Université de Bourgogne Franche-Comté, BP 87900, 21079, Dijon, Cedex, France.
| | - Jochen Fischer
- Institut für Biotechnologie und Wirkstoff-Forschung GmbH (IBWF), Kaiserslautern, Germany
| | - Anja Schüffler
- Institut für Biotechnologie und Wirkstoff-Forschung GmbH (IBWF), Kaiserslautern, Germany
| | - Clément Delaude
- Centre de Recherche Phytochimique, Université de Liège, Institut de Chimie-B6, Sart Tilman, 4000, Liège I, Belgium
| | - Tomofumi Miyamoto
- Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, 812-8582, Japan
| | - Chiaki Tanaka
- Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, 812-8582, Japan
| | - Eckhard Thines
- Institut für Biotechnologie und Wirkstoff-Forschung GmbH (IBWF), Kaiserslautern, Germany
| | - Marie-Aleth Lacaille-Dubois
- PEPITE EA 4267, Laboratoire de Pharmacognosie, UFR des Sciences de Santé, Université de Bourgogne Franche-Comté, BP 87900, 21079, Dijon, Cedex, France
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Novakovic M, Battistel MD, Azurmendi HF, Concilio MG, Freedberg DI, Frydman L. The Incorporation of Labile Protons into Multidimensional NMR Analyses: Glycan Structures Revisited. J Am Chem Soc 2021; 143:8935-8948. [PMID: 34085814 PMCID: PMC8297728 DOI: 10.1021/jacs.1c04512] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
![]()
Glycan structures
are often stabilized by a repertoire of hydrogen-bonded
donor/acceptor groups, revealing longer-lived structures that could
represent biologically relevant conformations. NMR provides unique
data on these hydrogen-bonded networks from multidimensional experiments
detecting cross-peaks resulting from through-bond (TOCSY) or through-space
(NOESY) interactions. However, fast OH/H2O exchange, and
the spectral proximity among these NMR resonances, hamper the use
of glycans’ labile protons in such analyses; consequently,
studies are often restricted to aprotic solvents or supercooled aqueous
solutions. These nonphysiological conditions may lead to unrepresentative
structures or to probing a small subset of accessible conformations
that may miss “active” glycan conformations. Looped,
projected spectroscopy (L-PROSY) has been recently shown to substantially
enhance protein NOESY and TOCSY cross-peaks, for 1Hs that
undergo fast exchange with water. This study shows that even larger
enhancements can be obtained for rapidly exchanging OHs in saccharides,
leading to the retrieval of previously undetectable 2D TOCSY/NOESY
cross-peaks with nonlabile protons. After demonstrating ≥300%
signal enhancements on model monosaccharides, these experiments were
applied at 1 GHz to elucidate the structural network adopted by a
sialic acid homotetramer, used as a model for α,2–8 linked
polysaccharides. High-field L-PROSY NMR enabled these studies at higher
temperatures and provided insight previously unavailable from lower-field
NMR investigations on supercooled samples, involving mostly nonlabile
nuclei. Using L-PROSY’s NOEs and other restraints, a revised
structural model for the homotetramer was obtained combining rigid
motifs and flexible segments, that is well represented by conformations
derived from 40 μs molecular dynamics simulations.
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Affiliation(s)
- Mihajlo Novakovic
- Department of Chemical and Biological Physics, Weizmann Institute of Science, 76100 Rehovot, Israel
| | - Marcos D Battistel
- Laboratory of Bacterial Polysaccharides, Center for Biologics Evaluation and Research, Food and Drug Administration, 10903 New Hampshire Avenue, Silver Spring, Maryland 20993, United States
| | - Hugo F Azurmendi
- Laboratory of Bacterial Polysaccharides, Center for Biologics Evaluation and Research, Food and Drug Administration, 10903 New Hampshire Avenue, Silver Spring, Maryland 20993, United States
| | - Maria-Grazia Concilio
- Department of Chemical and Biological Physics, Weizmann Institute of Science, 76100 Rehovot, Israel
| | - Darón I Freedberg
- Laboratory of Bacterial Polysaccharides, Center for Biologics Evaluation and Research, Food and Drug Administration, 10903 New Hampshire Avenue, Silver Spring, Maryland 20993, United States
| | - Lucio Frydman
- Department of Chemical and Biological Physics, Weizmann Institute of Science, 76100 Rehovot, Israel
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Olayinka JN, Ozolua RI, Akhigbemen AM. Phytochemical screening of aqueous leaf extract of Blighia sapida K.D. Koenig (Sapindaceae) and its analgesic property in mice. JOURNAL OF ETHNOPHARMACOLOGY 2021; 273:113977. [PMID: 33652110 DOI: 10.1016/j.jep.2021.113977] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 02/16/2021] [Accepted: 02/23/2021] [Indexed: 06/12/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Blighia sapida is traditionally used in treating intercostal pain, psychosis, stomach ache, back pain, and skin diseases. However, there is limited information on the scientific basis for its use traditionally in the treatment of pain. AIM OF STUDY To identify the major constituents in the aqueous leaf extract of Blighia sapida (AEBS) and to assess its analgesic properties in mice. MATERIALS AND METHODS Bioactive compounds were identified and quantified in AEBS by High Performance Liquid Chromatography/Photodiode Array Detector (HPLC/DAD). Analgesic activity of AEBS was assessed at doses of 125, 250, and 500 mg/kg p.o., using animal models. RESULTS Chlorogenic acid, saponins, tannins, caffeic acid, quercetin, gallic acid, pyrogallol, quinine, caffeine, and nicotine were identified. At doses 250 mg/kg (p < 0.05) and 500 mg/kg (p < 0.01), AEBS significantly inhibited acetic acid induced writhing in comparison with the control. It also significantly inhibited pain in the inflammatory phase of the formalin induced paw licking test at 250 mg/kg (p < 0.01) and 500 mg/kg (p < 0.05) doses, in comparison with the control. It did not inhibit pain in the neurogenic phase of the formalin paw licking and in the hot plate tests. CONCLUSION Blighia sapida leaf extract possesses analgesic activity that is mediated by peripheral mechanisms but not through central mechanisms.
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Affiliation(s)
- Juliet Nnenda Olayinka
- Department of Pharmacology and Therapeutics, College of Medicine and Health Sciences, Afe Babalola University, Ado Ekiti, Ekiti State, Nigeria; Department of Pharmacology and Toxicology, Faculty of Pharmacy, University of Benin, Benin City, 300001, Nigeria.
| | - Raymond Iduojemu Ozolua
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, University of Benin, Benin City, 300001, Nigeria
| | - Abigail Mebu Akhigbemen
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, University of Benin, Benin City, 300001, Nigeria
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Li W, Battistel MD, Reeves H, Oh L, Yu H, Chen X, Wang LP, Freedberg DI. A combined NMR, MD and DFT conformational analysis of 9-O-acetyl sialic acid-containing GM3 ganglioside glycan and its 9-N-acetyl mimic. Glycobiology 2020; 30:787-801. [PMID: 32350512 PMCID: PMC8179627 DOI: 10.1093/glycob/cwaa040] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 04/22/2020] [Accepted: 04/22/2020] [Indexed: 01/30/2023] Open
Abstract
O-Acetylation of carbohydrates such as sialic acids is common in nature, but its role is not clearly understood due to the lability of O-acetyl groups. We demonstrated previously that 9-acetamido-9-deoxy-N-acetylneuraminic acid (Neu5Ac9NAc) is a chemically and biologically stable mimic of the 9-O-acetyl-N-acetylneuraminic acid (Neu5,9Ac2) of the corresponding sialoglycans. Here, a systematic nuclear magnetic resonance (NMR) spectroscopic and molecular dynamics (MD) simulation study was undertaken for Neu5,9Ac2-containing GM3 ganglioside glycan (GM3-glycan) and its Neu5Ac9NAc analog. GM3-glycan with Neu5Ac as the non-O-acetyl form of Neu5,9Ac2 was used as a control. Complete 1H and 13C NMR chemical shift assignments, three-bond 1H-13C trans-glycosidic coupling constants (3JCH), accurate 1H-1H coupling constants (3JHH), nuclear Overhauser effects and hydrogen bonding detection were carried out. Results show that structural modification (O- or N-acetylation) on the C-9 of Neu5Ac in GM3 glycan does not cause significant conformational changes on either its glycosidic dihedral angles or its secondary structure. All structural differences are confined to the Neu5Ac glycerol chain, and minor temperature-dependent changes are seen in the aglycone portion. We also used Density Functional Theory (DFT) quantum mechanical calculations to improve currently used 3JHH Karplus relations. Furthermore, OH chemical shifts were assigned at -10°C and no evidence of an intramolecular hydrogen bond was observed. The results provide additional evidence regarding structural similarities between sialosides containing 9-N-acetylated and 9-O-acetylated Neu5Ac and support the opportunity of using 9-N-acetylated Neu5Ac as a stable mimic to study the biochemical role of 9-O-acetylated Neu5Ac.
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Affiliation(s)
- Wanqing Li
- Department of Chemistry, University of California-Davis, One Shields Avenue, Davis, California 95616, USA
| | - Marcos D Battistel
- Laboratory of Bacterial Polysaccharides, Food and Drug Administration (FDA), Silver Spring, MD 20993, USA
| | - Hannah Reeves
- Department of Chemistry, University of California-Davis, One Shields Avenue, Davis, California 95616, USA
| | - Lisa Oh
- Department of Chemistry, University of California-Davis, One Shields Avenue, Davis, California 95616, USA
| | - Hai Yu
- Department of Chemistry, University of California-Davis, One Shields Avenue, Davis, California 95616, USA
| | - Xi Chen
- Department of Chemistry, University of California-Davis, One Shields Avenue, Davis, California 95616, USA
| | - Lee-Ping Wang
- Department of Chemistry, University of California-Davis, One Shields Avenue, Davis, California 95616, USA
| | - Darón I Freedberg
- Laboratory of Bacterial Polysaccharides, Food and Drug Administration (FDA), Silver Spring, MD 20993, USA
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Petit B, Mitaine-Offer AC, Fernández FR, Papini AM, Delaude C, Miyamoto T, Tanaka C, Rovero P, Lacaille-Dubois MA. Triterpene glycosides from Blighia welwitschii and evaluation of their antibody recognition capacity in multiple sclerosis. PHYTOCHEMISTRY 2020; 176:112392. [PMID: 32512361 DOI: 10.1016/j.phytochem.2020.112392] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Revised: 04/11/2020] [Accepted: 04/15/2020] [Indexed: 06/11/2023]
Abstract
Multiple sclerosis (MS) in a multifactorial autoimmune disease in which reliable biomarkers are needed for therapeutic monitoring and diagnosis. Autoantibodies (autoAbs) are known biomarker candidates although their detection in biological fluids requires a thorough characterization of their associated antigens. Over the past twenty years, a reverse chemical-based approach aiming to screen putative autoantigens has underlined the role of glycans, in particular glucose, in MS. Despite the progress achieved, a lack of consensus regarding the nature of innate antigens as well as difficulties proposing new synthetic glucose-based structures have proved to be obstacles. Here is proposed a strategy to extend the current methodology to the field of natural glycosides, in order to dramatically increase the diversity of glycans that could be tested. Triterpene saponins from the Sapindaceace family represent an optimal starting material as their abundant description in the literature has revealed a prevalence of glucose-based oligosaccharides. Blighia welwitschii (Sapindaceae) was thus selected as a case study and twelve triterpene saponins were isolated and characterized. Their structures were elucidated on the basis of 1D and 2D NMR as well as mass spectrometry, revealing seven undescribed compounds. A selection of natural glycosides exhibiting various oligosaccharide moieties were then tested as antigens in enzyme-linked immunosorbent assay (ELISA) to recognize IgM antibodies (Abs) in MS patients' sera. Immunoassay results indicated a correlation between the glycan structures and their antibody recognition capacity, allowing the determination of structure-activity relationships that were coherent with previous studies. This approach might help to identify sugar epitopes putatively involved in MS pathogenesis, which remains poorly understood.
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Affiliation(s)
- Bastien Petit
- PEPITE EA 4267, Laboratoire de Pharmacognosie, UFR des Sciences de Santé, Université de Bourgogne Franche-Comté, BP 87900, 21079, Dijon, Cedex, France
| | - Anne-Claire Mitaine-Offer
- PEPITE EA 4267, Laboratoire de Pharmacognosie, UFR des Sciences de Santé, Université de Bourgogne Franche-Comté, BP 87900, 21079, Dijon, Cedex, France.
| | - Feliciana Real Fernández
- Interdepartmental Laboratory of Peptide and Protein Chemistry and Biology, University of Florence, 50019, Sesto Fiorentino, Italy; Department of Neurosciences, Psychology, Drug Research and Child Health, NeuroFarBa Section of Pharmaceutical Sciences and Nutraceutics, University of Florence, 50019, Sesto Fiorentino, Italy
| | - Anna Maria Papini
- Interdepartmental Laboratory of Peptide and Protein Chemistry and Biology, University of Florence, 50019, Sesto Fiorentino, Italy; Department of Chemistry "Ugo Schiff", University of Florence, 50019, Sesto Fiorentino, Italy; Laboratory of Chemical Biology, EA 4505 PeptLab@UCP, University of Cergy Pontoise, 95031, Cergy, Pontoise Cedex, France
| | - Clément Delaude
- Centre de Recherche Phytochimique, Université de Liège, Institut de Chimie-B6, Sart Tilman, B-4000, Liège I, Belgium
| | - Tomofumi Miyamoto
- Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, 812-8582, Japan
| | - Chiaki Tanaka
- Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, 812-8582, Japan
| | - Paolo Rovero
- Interdepartmental Laboratory of Peptide and Protein Chemistry and Biology, University of Florence, 50019, Sesto Fiorentino, Italy; Department of Neurosciences, Psychology, Drug Research and Child Health, NeuroFarBa Section of Pharmaceutical Sciences and Nutraceutics, University of Florence, 50019, Sesto Fiorentino, Italy
| | - Marie-Aleth Lacaille-Dubois
- PEPITE EA 4267, Laboratoire de Pharmacognosie, UFR des Sciences de Santé, Université de Bourgogne Franche-Comté, BP 87900, 21079, Dijon, Cedex, France
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9
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Plant terpenoid metabolism co-opts a component of the cell wall biosynthesis machinery. Nat Chem Biol 2020; 16:740-748. [PMID: 32424305 DOI: 10.1038/s41589-020-0541-x] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Accepted: 04/03/2020] [Indexed: 01/06/2023]
Abstract
Glycosylation is one of the most prevalent molecular modifications in nature. Single or multiple sugars can decorate a wide range of acceptors from proteins to lipids, cell wall glycans and small molecules, dramatically affecting their activity. Here, we discovered that by 'hijacking' an enzyme of the cellulose synthesis machinery involved in cell wall assembly, plants evolved cellulose synthase-like enzymes (Csls) and acquired the capacity to glucuronidate specialized metabolites, that is, triterpenoid saponins. Apparently, endoplasmic reticulum-membrane localization of Csls and of other pathway proteins was part of evolving a new glycosyltransferase function, as plant metabolite glycosyltransferases typically act in the cytosol. Discovery of glucuronic acid transferases across several plant orders uncovered the long-pursued enzymatic reaction in the production of a low-calorie sweetener from licorice roots. Our work opens the way for engineering potent saponins through microbial fermentation and plant-based systems.
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Paul TJ, Taylor TA, Rajendra Santosh AB. The potential of saponin from Jamaica’s Blighia sapida (ackee) as a substitute for sodium lauryl sulphate in toothpaste. Med Hypotheses 2020; 137:109555. [DOI: 10.1016/j.mehy.2020.109555] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 12/19/2019] [Accepted: 01/05/2020] [Indexed: 11/26/2022]
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Sychrovský V, Šaman D, Fiala R, Humpa O, Sýkora J, Kessler P, Blechta V, Dobrev P, Schraml J. Ascorbigen A-NMR identification. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2019; 57:1084-1096. [PMID: 31257662 DOI: 10.1002/mrc.4890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 05/03/2019] [Accepted: 05/06/2019] [Indexed: 06/09/2023]
Abstract
The connectivities of all atoms in ascorbigen A, an important metabolite, were determined unambiguously for the first time. The connectivity between carbon atoms was established by 2D INADEQUATE, and one-bond 13 C-13 C coupling constants were determined for all pairs of directly connected carbon atoms except for two strongly coupled carbon pairs. The 13 C-13 C coupling in one of the pairs was proved by a modification of standard INADEQUATE; however, the signals from the other pair were too weak to be observed. The connectivity within the two strongly coupled C-C pairs was confirmed by a combination of COSY and gHSQC; the latter experiment also identified all C-H bonds. The proton nuclear magnetic resonance (1 H NMR) spectra in dry dimethyl sulfoxide allowed identification and assignment of the signals due to NH and OH protons. The derived structure, 3-((1H-indol-3-yl)methyl)-3,3a,6-trihydroxytetrahydrofuro[3,2-b]furan-2(5H)-one, agrees with the structure suggested for ascorbigen A in 1966. The density functional theory (DFT) calculations showed that among 16 possible stereoisomers, only two complied with the almost zero value of the measured 3 J(H6-H6a). Of the two stereoisomers, 3S,3aS,6S,6aR and 3R,3aR,6R,6aS, the latter was excluded on synthetic grounds. The nuclear Overhauser effect measurements unveiled close proximity between H2' proton of the indole and the H6a proton of the tetrahydrofuro[3,2-b]furan part. Detailed structural interpretation of the measured NMR parameters by means of DFT NMR was hampered by rotational flexibility of the indole and tetrahydrofuro[3,2-b]furan parts and inadequacy of Polarizable Continuum Model (PCM) solvent model.
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Affiliation(s)
- Vladimír Sychrovský
- Institute of Organic Chemistry and Biochemistry of the CAS, Prague 6, Czech Republic
| | - David Šaman
- Institute of Organic Chemistry and Biochemistry of the CAS, Prague 6, Czech Republic
| | | | | | - Jan Sýkora
- Institute of Chemical Process Fundamentals of the CAS, Prague 6, Czech Republic
| | | | - Vratislav Blechta
- Institute of Chemical Process Fundamentals of the CAS, Prague 6, Czech Republic
| | - Petre Dobrev
- Institute of Experimental Botany of the CAS, Prague 6, Czech Republic
| | - Jan Schraml
- Institute of Chemical Process Fundamentals of the CAS, Prague 6, Czech Republic
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Petit B, Mitaine-Offer AC, Delaude C, Miyamoto T, Tanaka C, Lacaille-Dubois MA. Hederagenin glycosides from the fruits of Blighia unijugata. PHYTOCHEMISTRY 2019; 162:260-269. [PMID: 31031211 DOI: 10.1016/j.phytochem.2019.03.020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Revised: 03/20/2019] [Accepted: 03/22/2019] [Indexed: 06/09/2023]
Abstract
A phytochemical investigation of Blighia unijugata led to the isolation of eleven hederagenin glycosides. Among these compounds, six are previously undescribed, two are described in their native forms for the first time and three are known whereas firstly isolated from Blighia unijugata. The structure of the undescribed compounds was elucidated on the basis of 2D NMR and mass spectrometry analyses as 3-O-β-D-xylopyranosyl-(1 → 3)-α-L-arabinopyranosyl-(1 → 4)-β-D-glucopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosylhederagenin, 3-O-β-D-xylopyranosyl-(1 → 3)-α-L-arabinopyranosyl-(1 → 4)-3-O-acetyl-β-D-glucopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosylhederagenin, 3-O-β-D-glucopyranosyl-(1 → 3)-α-L-arabinopyranosyl-(1 → 4)-β-D-glucopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosylhederagenin, 3-O-β-D-xylopyranosyl-(1 → 3)-β-D-xylopyranosyl-(1 → 4)-β-D-glucopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosylhederagenin, 3-O-β-D-xylopyranosyl-(1 → 3)-β-D-xylopyranosyl-(1 → 4)-3-O-acetyl-β-D-glucopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosylhederagenin, 3-O-α-L-arabinopyranosyl-(1 → 4)-β-D-glucopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosylhederagenin 28-O-β-D-glucopyranosyl-(1 → 6)-β-D-glucopyranosyl ester, 3-O-α-L-arabinopyranosyl-(1 → 4)-β-D-glucopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosylhederagenin 28-O-β-D-glucopyranosyl ester and 3-O-β-D-xylopyranosyl-(1 → 4)-β-D-glucopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosylhederagenin 28-O-β-D-glucopyranosyl ester. These results revealed the existence of several conserved structural features that could be used as chemotaxonomic markers for the Blighia genus such as the glycosidic sequence 3-O-α-L-arabinopyranosyl-(1 → 4)-β-D-glucopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosyl, the occurrence of 3-O-acetylated β-D-glucopyranosyl units and the systematic presence of hederagenin as aglycone.
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Affiliation(s)
- Bastien Petit
- PEPITE EA 4267, Laboratoire de Pharmacognosie, UFR des Sciences de Santé, Université de Bourgogne Franche-Comté, BP 87900, 21079, Dijon Cedex, France
| | - Anne-Claire Mitaine-Offer
- PEPITE EA 4267, Laboratoire de Pharmacognosie, UFR des Sciences de Santé, Université de Bourgogne Franche-Comté, BP 87900, 21079, Dijon Cedex, France
| | - Clément Delaude
- Centre de Recherche Phytochimique, Université de Liège, Institut de Chimie-B6, Sart Tilman, B-4000, Liège I, Belgium
| | - Tomofumi Miyamoto
- Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, 812-8582, Japan
| | - Chiaki Tanaka
- Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, 812-8582, Japan
| | - Marie-Aleth Lacaille-Dubois
- PEPITE EA 4267, Laboratoire de Pharmacognosie, UFR des Sciences de Santé, Université de Bourgogne Franche-Comté, BP 87900, 21079, Dijon Cedex, France.
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Sinmisola A, Oluwasesan BM, Chukwuemeka AP. Blighia sapida K.D. Koenig: A review on its phytochemistry, pharmacological and nutritional properties. JOURNAL OF ETHNOPHARMACOLOGY 2019; 235:446-459. [PMID: 30685434 DOI: 10.1016/j.jep.2019.01.017] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Revised: 01/23/2019] [Accepted: 01/23/2019] [Indexed: 06/09/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Ackee plant (Blighia sapida K. D. Koenig) (Sapindaceae) is used in Sub-Saharan Africa (where it has its origin) and in different parts of the world (The Caribbean, North and South America, Europe). Traditionally it is used to manage numerous ailments like backache, constipation, cancer, fever in young children, gonorrhea, dysentery, psychosis, hernia, stomach ache, malaria, rheumatism, typhoid etc. It is also used as a cosmetic and food source. The fruit aril is the main constituent of the Jamaican National Dish. This review summarizes its phytochemistry, nutritional properties, ethnobotany and pharmacology. The need to gather up to date information on this plant, to facilitate in vivo and in vitro investigations for verification of some of the local claims necessitated this review. MATERIALS AND METHODS A literature search was performed on Ackee using ethno botanical text books and scientific databases such as PubMed, Scopus, EBSCO, Science-direct, Google, Google Scholar and other web sources like records from PROTA, PROSEA, JSTOR and Botanical Dermatology Database. RESULTS AND DISCUSSION This review highlights the traditional uses of parts of the Ackee plant: the bark, the leaves, capsules, roots and seeds. They are used in the management of diverse disease conditions such as diarrhoea, conjunctivitis, fever, internal hemorrhage, dysentery, cutaneous skin infections, and bacterial infections amongst others. Only nineteen compounds have been reportedly isolated from the parts of B. sapida; Alkaloids, quinines, polyphenols, and steroids, their glycosides, sesquiterpenes and triterpenes. Some of the plant extracts and its isolated compounds showed anticancer, antimicrobial, antidiarrheal, antioxidant and hypoglycemic activities both in vitro and in vivo. The seed/leaves have also been used as insect repellants and the leaves have been reported to have lethal effects on larvae of various mosquitoes' species. The oil contains a lot of nutrients and may be considered for edible consumption after safety has been confirmed. Hypoglycin A and the less malignant hypoglycin B are found in the unripe aril of Ackee and consumption results in hypoglycemia, vomiting, gluconeogenesis disruption which can result in coma and death. The untapped economic potential of its fruits is glaring in West Africa countries. CONCLUSION Though B.sapida has been put to enormous traditional use, the pharmacological studies conducted are not sufficient, most studies are either in-vivo or in-vitro. More work is required (well-designed pharmacological tests, randomized clinical trials) to evaluate these medicinal claims. This review provides a basis for future research. The isolation of more compounds,detailed pharmacological investigations, exploration of food use and detoxification techniques are key areas to investigate.
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Affiliation(s)
- Aloko Sinmisola
- Dept of Pharmaceutics & Pharmaceutical Technology, Faculty of Pharmacy, University of Lagos, Nigeria.
| | - Bello M Oluwasesan
- Dept. of Applied Chemistry, Federal University Dutsin-Ma, Katsina State, Nigeria; National Center for Natural Products Research, School of Pharmacy, The University of Mississippi, University, MS 38677, USA
| | - Azubuike P Chukwuemeka
- Dept of Pharmaceutics & Pharmaceutical Technology, Faculty of Pharmacy, University of Lagos, Nigeria
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Hotchkiss AT, Nuñez A, Strahan GD, Chau HK, White AK, Marais JPJ, Hom K, Vakkalanka MS, Di R, Yam KL, Khoo C. Cranberry Xyloglucan Structure and Inhibition of Escherichia coli Adhesion to Epithelial Cells. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2015; 63:5622-5633. [PMID: 25973733 DOI: 10.1021/acs.jafc.5b00730] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Cranberry juice has been recognized as a treatment for urinary tract infections on the basis of scientific reports of proanthocyanidin anti-adhesion activity against Escherichia coli as well as from folklore. Xyloglucan oligosaccharides were detected in cranberry juice and the residue remaining following commercial juice extraction that included pectinase maceration of the pulp. A novel xyloglucan was detected through tandem mass spectrometry analysis of an ion at m/z 1055 that was determined to be a branched, three hexose, four pentose oligosaccharide consistent with an arabino-xyloglucan structure. Two-dimensional nuclear magnetic resonance spectroscopy analysis provided through-bond correlations for the α-L-Araf (1→2) α-D-Xylp (1→6) β-D-Glcp sequence, proving the S-type cranberry xyloglucan structure. Cranberry xyloglucan-rich fractions inhibited the adhesion of E. coli CFT073 and UTI89 strains to T24 human bladder epithelial cells and that of E. coli O157:H7 to HT29 human colonic epithelial cells. SSGG xyloglucan oligosaccharides represent a new cranberry bioactive component with E. coli anti-adhesion activity and high affinity for type 1 fimbriae.
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Affiliation(s)
- Arland T Hotchkiss
- †Eastern Regional Research Center, Agricultural Research Service, U.S. Department of Agriculture, 600 East Mermaid Lane, Wyndmoor, Pennsylvania 19038, United States
| | - Alberto Nuñez
- †Eastern Regional Research Center, Agricultural Research Service, U.S. Department of Agriculture, 600 East Mermaid Lane, Wyndmoor, Pennsylvania 19038, United States
| | - Gary D Strahan
- †Eastern Regional Research Center, Agricultural Research Service, U.S. Department of Agriculture, 600 East Mermaid Lane, Wyndmoor, Pennsylvania 19038, United States
| | - Hoa K Chau
- †Eastern Regional Research Center, Agricultural Research Service, U.S. Department of Agriculture, 600 East Mermaid Lane, Wyndmoor, Pennsylvania 19038, United States
| | - André K White
- †Eastern Regional Research Center, Agricultural Research Service, U.S. Department of Agriculture, 600 East Mermaid Lane, Wyndmoor, Pennsylvania 19038, United States
| | - Jannie P J Marais
- ‡Ocean Spray Cranberries, Inc., One Ocean Spray Drive, Lakeville-Middleboro, Massachusetts 02349, United States
| | - Kellie Hom
- §Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, 20 North Pine Street, Baltimore, Maryland 21201, United States
| | - Malathi S Vakkalanka
- #Department of Food Science, Rutgers University, 65 Dudley Road, New Brunswick, New Jersey 08901, United States
| | - Rong Di
- ⊥Department of Plant Biology and Pathology, Rutgers University, 59 Dudley Road, New Brunswick, New Jersey 08901, United States
| | - Kit L Yam
- #Department of Food Science, Rutgers University, 65 Dudley Road, New Brunswick, New Jersey 08901, United States
| | - Christina Khoo
- ‡Ocean Spray Cranberries, Inc., One Ocean Spray Drive, Lakeville-Middleboro, Massachusetts 02349, United States
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Reynolds WF, Mazzola EP. Nuclear magnetic resonance in the structural elucidation of natural products. PROGRESS IN THE CHEMISTRY OF ORGANIC NATURAL PRODUCTS 2015; 100:223-309. [PMID: 25632562 DOI: 10.1007/978-3-319-05275-5_3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
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Trigo-Mouriño P, de la Fuente MC, Gil RR, Sánchez-Pedregal VM, Navarro-Vázquez A. Conformational Analysis of the Anti-obesity Drug Lorcaserin in Water: How To Take Advantage of Long-Range Residual Dipolar Couplings. Chemistry 2013; 19:14989-97. [DOI: 10.1002/chem.201202509] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2012] [Revised: 06/28/2013] [Indexed: 11/07/2022]
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Abstract
This review covers the isolation and structure determination of triterpenoids including squalene derivatives, lanostanes, holostanes, cycloartanes, cucurbitanes, dammaranes, euphanes, tirucallanes, tetranortriterpenoids, quassinoids, lupanes, oleananes, friedelanes, ursanes, hopanes, onoceranes and saponins; 308 references are cited.
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Affiliation(s)
- Robert A Hill
- School of Chemistry, Glasgow University, Glasgow G12 8QQ, UK.
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Abstract
Over the past 28 years there have been several thousand publications describing the use of 2D NMR to identify and characterize natural products. During this time period, the amount of sample needed for this purpose has decreased from the 20-50 mg range to under 1 mg. This has been due to both improvements in NMR hardware and methodology. This review will focus on mainly methodology improvements, particularly in pulse sequences, acquisition and processing methods which are particularly relevant to natural product research, with lesser discussion of hardware improvements.
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Powder-George Y, Frank J, Ramsewak RS, Reynolds WF. The use of coupled HSQC spectra to aid in stereochemical assignments of molecules with severe proton spectral overlap. PHYTOCHEMICAL ANALYSIS : PCA 2012; 23:274-277. [PMID: 21898630 DOI: 10.1002/pca.1354] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2011] [Revised: 07/11/2011] [Accepted: 07/12/2011] [Indexed: 05/31/2023]
Abstract
INTRODUCTION A simple glycoside with only 13 carbons exhibited extensive overlapping of four of the glycosidic protons, causing extreme difficulty in the determination of the stereochemistry of the pyranose unit. However, acquisition of a high-resolution coupled heteronuclear single-quantum coherence (HSQC) spectrum overcame this problem. This spectrum provides a useful method for determining vicinal proton coupling constants between strongly coupled protons. OBJECTIVE To show the potential of high-resolution coupled HSQC spectra in overcoming spectral overlap. METHODOLOGY The sample was obtained by methanol extraction, followed by fractionation and column chromatography of the dried leaves of Montrichardia arborescens (Araceae). NMR spectra were obtained on 1.5 mg of sample dissolved in 120 μL of CD₃OD containing 0.1% trimethylsilyl (TMS) as internal standard. A gradient-selected HSQC spectrum was obtained using standard Varian library pulse sequences in phase sensitive mode. The high-resolution coupled HSQC spectrum focused on the saccharide region with a 1025 Hz ¹H spectral window, a 6300 Hz ¹³C spectral window, 1024 data points, a 0.3 Hz relaxation delay, 384 time increments (linear predicted to 4096), and 80 scans per time increment. RESULTS The use of a high-resolution coupled HSQC spectrum allowed determination of the coupling patterns of the various pyranose protons with sufficient accuracy. This enabled completion of the assignments and identification of the pyranose unit as glucose. CONCLUSION The study has shown the effectiveness of the use of a high-resolution coupled HSQC spectrum in the assignment of molecules with severe spectral overlap.
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Affiliation(s)
- Yomica Powder-George
- Department of Chemistry, The University of the West Indies, St. Augustine, Trinidad and Tobago
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