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Development and Evaluation of Matrices Composed of β-cyclodextrin and Biodegradable Polyesters in the Controlled Delivery of Pindolol. Pharmaceutics 2020; 12:pharmaceutics12060500. [PMID: 32486203 PMCID: PMC7355766 DOI: 10.3390/pharmaceutics12060500] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 05/20/2020] [Accepted: 05/27/2020] [Indexed: 11/24/2022] Open
Abstract
Polymer-drug conjugates are currently being more widely investigated for the treatment of hypertension. In view of the above, in the first stage of our work, we used nontoxic β-cyclodextrin (β-CD) as effective, simple, inexpensive, and safe for the human body initiator for the synthesis of biocompatible and biodegradable functionalized polymers suitable for the medical and pharmaceutical applications. The obtained polymeric products were synthesized through a ring-opening polymerization (ROP) of ε-caprolactone (CL), d,l-, and l,l-lactide (LA and LLA). The chemical structures of synthesized materials were elucidated based on 1H NMR and solid-state carbon-13 cross-polarization/magic angle spinning nuclear magnetic resonance (13C CP/MAS NMR) analysis, while the incorporation of β-CD molecule into the polymer chain was confirmed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Furthermore, molecular modeling has been applied to investigate the intrachain rigidities and chain architectures for several representative structures. The obtained and thoroughly characterized branched matrices were then used to generate the first β-cyclodextrin/biodegradable polymer/β-blocker conjugate through the successful conjugation of pindolol. The conjugates were fabricated by carbodiimide-mediated coupling reaction. The branched biodegradable materials released the drug in vitro in a sustained manner and without “burst release” and thus have the ability to treat different heart diseases.
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Barbosa JS, Nolasco MM, Ribeiro-Claro P, Almeida Paz FA, Braga SS. Preformulation Studies of the γ-Cyclodextrin and Montelukast Inclusion Compound Prepared by Comilling. J Pharm Sci 2019; 108:1837-1847. [DOI: 10.1016/j.xphs.2018.11.047] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Revised: 11/15/2018] [Accepted: 11/27/2018] [Indexed: 12/17/2022]
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Wałejko P, Bukowicki J, Dobrzycki Ł, Socha P, Paradowska K. Phenyl glycosides – Solid-state NMR, X-ray diffraction and conformational analysis using genetic algorithm. Chem Phys 2019. [DOI: 10.1016/j.chemphys.2018.12.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Supramolecular adducts of native and permethylated β-cyclodextrins with (2,2′-dipyridylamine)chlorido(1,4,7-trithiacyclononane)ruthenium(II) chloride: solid-state and biological activity studies. CHEMICAL PAPERS 2017. [DOI: 10.1007/s11696-016-0117-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Le-Bail P, Lorentz C, Pencreac’h G, Soultani-Vigneron S, Pontoire B, Giraldo LL, Villeneuve P, Hendrickx J, Tran V. Trapping by amylose of the aliphatic chain grafted onto chlorogenic acid: Importance of the graft position. Carbohydr Polym 2015; 117:910-916. [DOI: 10.1016/j.carbpol.2014.10.029] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Revised: 09/16/2014] [Accepted: 10/02/2014] [Indexed: 11/26/2022]
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Fernandes JA, Ramos AI, Ribeiro-Claro P, Almeida Paz FA, Braga SS. Studies on polymorph conversion in a new cyclodextrin inclusion compound. CrystEngComm 2015. [DOI: 10.1039/c4ce02041c] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
4-Phenylpyridine-N-oxide and βCD form a stoichiometric inclusion complex with two polymorphs occurring at different crystallisation times. The irreversible conversion of one polymorph into the other was monitored in real time for the first time.
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Affiliation(s)
- José A. Fernandes
- QOPNA (Research Unit on Organic Chemistry
- Natural and Agroalimentary Products)
- Department of Chemistry
- CICECO
- University of Aveiro
| | - Ana I. Ramos
- QOPNA (Research Unit on Organic Chemistry
- Natural and Agroalimentary Products)
- Department of Chemistry
- CICECO
- University of Aveiro
| | - Paulo Ribeiro-Claro
- QOPNA (Research Unit on Organic Chemistry
- Natural and Agroalimentary Products)
- Department of Chemistry
- CICECO
- University of Aveiro
| | - Filipe A. Almeida Paz
- QOPNA (Research Unit on Organic Chemistry
- Natural and Agroalimentary Products)
- Department of Chemistry
- CICECO
- University of Aveiro
| | - Susana S. Braga
- QOPNA (Research Unit on Organic Chemistry
- Natural and Agroalimentary Products)
- Department of Chemistry
- CICECO
- University of Aveiro
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Larsen FH, Kasprzak MM, Lærke HN, Knudsen KEB, Pedersen S, Jørgensen AS, Blennow A. Hydration properties and phosphorous speciation in native, gelatinized and enzymatically modified potato starch analyzed by solid-state MAS NMR. Carbohydr Polym 2013; 97:502-11. [DOI: 10.1016/j.carbpol.2013.05.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2013] [Accepted: 05/08/2013] [Indexed: 11/28/2022]
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Analysis of the microcrystalline inclusion compounds of triclosan with β-cyclodextrin and its tris-O-methylated derivative. J Pharm Biomed Anal 2013; 80:34-43. [PMID: 23523864 DOI: 10.1016/j.jpba.2013.02.033] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2013] [Revised: 02/18/2013] [Accepted: 02/21/2013] [Indexed: 11/24/2022]
Abstract
Solid 1:1 inclusion compounds of triclosan with native and permethylated β-cyclodextrin (β-CD and TRIMEB) were prepared by co-crystallisation and co-evaporation, respectively, and studied by FT-IR and (13)C{(1)H} CP/MAS NMR spectroscopies, thermogravimetric analysis, X-ray diffraction and theoretical calculations. Results showed that triclosan inclusion into TRIMEB afforded an amorphous solid, whilst β-CD·triclosan is composed of microcrystals belonging to two different phases. In the phase featuring larger crystals, X-ray diffraction was carried out and the β-CD host units, packing head-to-head in infinite channels, were refined; the geometry for the included but highly disordered triclosan molecules was assessed by theoretical calculations. The bacterial growth inhibitory action of the inclusion compounds was studied in comparison to that of pure triclosan on Gram-negative (Salmonella, Escherichia) and Gram-positive strains (Bacillus, Listeria, Enterococcus and Staphylococcus) typically associated with human pathologies, and also on environmental bacteria isolated from different soil and water sources. The antimicrobial activities obtained in the present work showed that, of the two CD hosts, TRIMEB brings the most favourable carrier effect: it reduced the toxicity of triclosan against some of the environmental strains and afforded slightly higher action against virulent strains.
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Ramos AI, Braga TM, Silva P, Fernandes JA, Ribeiro-Claro P, Lopes MDFS, Paz FAA, Braga SS. Chloramphenicol·cyclodextrin inclusion compounds: co-dissolution and mechanochemical preparations and antibacterial action. CrystEngComm 2013. [DOI: 10.1039/c3ce26414a] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Bruno SM, Fernandes JA, Marques J, Neto SC, Ribeiro-Claro PJ, Pillinger M, Paz FAA, Marques MPM, Braga SS, Gonçalves IS. Structural Studies and Cytotoxicity of Trimethyl(ferrocenylmethyl)ammonium Iodide Encapsulated in β-Cyclodextrin. Eur J Inorg Chem 2011. [DOI: 10.1002/ejic.201100657] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Braga SS, GonÇalves IS, Ribeiro-Claro P, Lopes AD, Pillinger M, Teixeira-Dias JJ, Rocha J, Romão CC. Encapsulation of Cyano(cyclopentadienyl) Complexes of Iron with β-cyclodextrin. Supramol Chem 2010. [DOI: 10.1080/10610270290029308] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Affiliation(s)
- Susana S. Braga
- a Department of Chemistry , University of Aveiro , Campus de Santiago, Aveiro , 3810-193 , Portugal
| | - Isabel S. GonÇalves
- a Department of Chemistry , University of Aveiro , Campus de Santiago, Aveiro , 3810-193 , Portugal
| | - Paulo Ribeiro-Claro
- a Department of Chemistry , University of Aveiro , Campus de Santiago, Aveiro , 3810-193 , Portugal
- b Química-Física Molecular, Faculdade de Ciências e Tecnologia , Universidade de Coimbra , Coimbra , 3004-353 , Portugal
| | - André D. Lopes
- a Department of Chemistry , University of Aveiro , Campus de Santiago, Aveiro , 3810-193 , Portugal
| | - Martyn Pillinger
- a Department of Chemistry , University of Aveiro , Campus de Santiago, Aveiro , 3810-193 , Portugal
| | - José J.C. Teixeira-Dias
- a Department of Chemistry , University of Aveiro , Campus de Santiago, Aveiro , 3810-193 , Portugal
| | - João Rocha
- a Department of Chemistry , University of Aveiro , Campus de Santiago, Aveiro , 3810-193 , Portugal
| | - Carlos C. Romão
- c Quinta do Marquês , Instituto de Tecnologia Química e Biológica , EAN Apt 127, Oeiras , 2781-901 , Portugal
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Khatoon S, Sreerama Y, Raghavendra D, Bhattacharya S, Bhat K. Properties of enzyme modified corn, rice and tapioca starches. Food Res Int 2009. [DOI: 10.1016/j.foodres.2009.07.025] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Cyclodextrins improve the antimicrobial activity of the chloride salt of Ruthenium(II) chloro-phenanthroline-trithiacyclononane. Biometals 2009; 22:541-56. [DOI: 10.1007/s10534-009-9211-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2008] [Accepted: 01/19/2009] [Indexed: 10/21/2022]
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Marques J, Santos TM, Marques MP, Braga SS. A glycine ruthenium trithiacyclononane complex and its molecular encapsulation using cyclodextrins. Dalton Trans 2009:9812-9. [PMID: 19885528 DOI: 10.1039/b915839a] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Affiliation(s)
- Joana Marques
- Department of Chemistry, CICECO, University of Aveiro, 3810-193, Aveiro, Portugal
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Marques J, Anjo L, Marques MP, Santos TM, Almeida Paz FA, Braga SS. Structural studies on supramolecular adducts of cyclodextrins with the complex [Ru([9]aneS3)(bpy)Cl]Cl. J Organomet Chem 2008. [DOI: 10.1016/j.jorganchem.2008.06.023] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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TAN N, PAN JH, WANG SY, XU F, TAO YW, SHE ZG, LIN YC. Asymmetric Synthesis of 2-Methoxy-2-methylchroman-7-ol in Solid-stateβ-Cyclodextrin Complexes. CHINESE J CHEM 2008. [DOI: 10.1002/cjoc.200890138] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Petrovski Ž, Norton de Matos MR, Braga SS, Pereira CC, Matos ML, Gonçalves IS, Pillinger M, Alves PM, Romão CC. Synthesis, characterization and antitumor activity of 1,2-disubstituted ferrocenes and cyclodextrin inclusion complexes. J Organomet Chem 2008. [DOI: 10.1016/j.jorganchem.2007.11.053] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Shao L, Yates JR, Titman JJ. Carbon-13 chemical shift tensors of disaccharides: measurement, computation and assignment. J Phys Chem A 2007; 111:13126-32. [PMID: 17999473 DOI: 10.1021/jp075921b] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A recently developed chemical shift anisotropy amplification solid-state nuclear magnetic resonance (NMR) experiment is applied to the measurement of the chemical shift tensors in three disaccharides: sucrose, maltose, and trehalose. The measured tensor principal values are compared with those calculated from first principles using density functional theory within the planewave-pseudopotential approach. In addition, a method of assigning poorly dispersed NMR spectra, based on comparing experimental and calculated shift anisotropies as well as isotropic shifts, is demonstrated.
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Affiliation(s)
- Limin Shao
- School of Chemistry, University of Nottingham, University Park, Nottingham, NG7 2RD, UK
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Host–guest interactions between niobocene dichloride and α-, β-, and γ-cyclodextrins: preparation and characterization. J INCL PHENOM MACRO 2007. [DOI: 10.1007/s10847-007-9374-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Pereira CCL, Nolasco M, Braga SS, Paz FAA, Ribeiro-Claro P, Pillinger M, Gonçalves IS. A Combined Theoretical−Experimental Study of the Inclusion of Niobocene Dichloride in Native and Permethylated β-Cyclodextrins. Organometallics 2007. [DOI: 10.1021/om7003749] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
| | - Mariela Nolasco
- Department of Chemistry, CICECO, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Susana S. Braga
- Department of Chemistry, CICECO, University of Aveiro, 3810-193 Aveiro, Portugal
| | | | - Paulo Ribeiro-Claro
- Department of Chemistry, CICECO, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Martyn Pillinger
- Department of Chemistry, CICECO, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Isabel S. Gonçalves
- Department of Chemistry, CICECO, University of Aveiro, 3810-193 Aveiro, Portugal
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β-Cyclodextrin and permethylated β-cyclodextrin inclusion compounds of a cyclopentadienyl molybdenum tricarbonyl complex and their use as cyclooctene epoxidation catalyst precursors. Inorganica Chim Acta 2006. [DOI: 10.1016/j.ica.2006.03.017] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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23
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Pereira CCL, Braga SS, Paz FAA, Pillinger M, Klinowski J, Gonçalves IS. Structural Studies of [CpMoL2(CO)2]+ (L = NCMe, L2 = 2,2′-biimidazole) Complexes and Their Inclusion Compounds with Cyclodextrins. Eur J Inorg Chem 2006. [DOI: 10.1002/ejic.200600551] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Rondeau-Mouro C, Veronese G, Buleon A. High-Resolution Solid-State NMR of B-Type Amylose. Biomacromolecules 2006; 7:2455-60. [PMID: 16903696 DOI: 10.1021/bm060330x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- C Rondeau-Mouro
- UR BIA-INRA, Laboratoire de RMN, Plate-forme-BIBS, Rue de la Géraudière, BP 71627, 44316 Nantes Cedex 3, France.
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Fernandes JA, Braga SS, Pillinger M, Sá Ferreira RA, Carlos LD, Hazell A, Ribeiro-Claro P, Gonçalves IS. β-Cyclodextrin inclusion of europium(III) tris(β-diketonate)-bipyridine. Polyhedron 2006. [DOI: 10.1016/j.poly.2005.10.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Braga SS, Almeida Paz FA, Pillinger M, Seixas JD, Romão CC, Gonçalves IS. Structural Studies of β-Cyclodextrin and Permethylated β-Cyclodextrin Inclusion Compounds of Cyclopentadienyl Metal Carbonyl Complexes. Eur J Inorg Chem 2006. [DOI: 10.1002/ejic.200501006] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Fernandes JA, Lima S, Braga SS, Pillinger M, Rodríguez-Borges JE, Ribeiro-Claro P, Teixeira-Dias JJC, Gonçalves IS. Experimental and Theoretical Study of the Encapsulation of a Linear Oligo(ferrocenylsilane) Trimer with β-Cyclodextrin. Eur J Inorg Chem 2005. [DOI: 10.1002/ejic.200500551] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Fernandes JA, Lima S, Braga SS, Pillinger M, Ribeiro-Claro P, Rodriguez-Borges JE, Lopes AD, Teixeira-Dias JJC, Gonçalves IS. Inclusion Complexation of Dimeric and Trimeric Oligo(ferrocenyldimethylsilanes) with γ-Cyclodextrin. Organometallics 2005. [DOI: 10.1021/om050654m] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- José A. Fernandes
- Department of Chemistry, CICECO, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal, CIQ, Department of Chemistry, University of Porto, Rua do Campo Alegre, 4169-007 Porto, Portugal, and Department of Chemistry and Biochemistry, Faculty of Science and Technology, University of the Algarve, Campus de Gambelas, 8000-062 Faro, Portugal
| | - Sérgio Lima
- Department of Chemistry, CICECO, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal, CIQ, Department of Chemistry, University of Porto, Rua do Campo Alegre, 4169-007 Porto, Portugal, and Department of Chemistry and Biochemistry, Faculty of Science and Technology, University of the Algarve, Campus de Gambelas, 8000-062 Faro, Portugal
| | - Susana S. Braga
- Department of Chemistry, CICECO, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal, CIQ, Department of Chemistry, University of Porto, Rua do Campo Alegre, 4169-007 Porto, Portugal, and Department of Chemistry and Biochemistry, Faculty of Science and Technology, University of the Algarve, Campus de Gambelas, 8000-062 Faro, Portugal
| | - Martyn Pillinger
- Department of Chemistry, CICECO, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal, CIQ, Department of Chemistry, University of Porto, Rua do Campo Alegre, 4169-007 Porto, Portugal, and Department of Chemistry and Biochemistry, Faculty of Science and Technology, University of the Algarve, Campus de Gambelas, 8000-062 Faro, Portugal
| | - Paulo Ribeiro-Claro
- Department of Chemistry, CICECO, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal, CIQ, Department of Chemistry, University of Porto, Rua do Campo Alegre, 4169-007 Porto, Portugal, and Department of Chemistry and Biochemistry, Faculty of Science and Technology, University of the Algarve, Campus de Gambelas, 8000-062 Faro, Portugal
| | - José E. Rodriguez-Borges
- Department of Chemistry, CICECO, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal, CIQ, Department of Chemistry, University of Porto, Rua do Campo Alegre, 4169-007 Porto, Portugal, and Department of Chemistry and Biochemistry, Faculty of Science and Technology, University of the Algarve, Campus de Gambelas, 8000-062 Faro, Portugal
| | - André D. Lopes
- Department of Chemistry, CICECO, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal, CIQ, Department of Chemistry, University of Porto, Rua do Campo Alegre, 4169-007 Porto, Portugal, and Department of Chemistry and Biochemistry, Faculty of Science and Technology, University of the Algarve, Campus de Gambelas, 8000-062 Faro, Portugal
| | - José J. C. Teixeira-Dias
- Department of Chemistry, CICECO, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal, CIQ, Department of Chemistry, University of Porto, Rua do Campo Alegre, 4169-007 Porto, Portugal, and Department of Chemistry and Biochemistry, Faculty of Science and Technology, University of the Algarve, Campus de Gambelas, 8000-062 Faro, Portugal
| | - Isabel S. Gonçalves
- Department of Chemistry, CICECO, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal, CIQ, Department of Chemistry, University of Porto, Rua do Campo Alegre, 4169-007 Porto, Portugal, and Department of Chemistry and Biochemistry, Faculty of Science and Technology, University of the Algarve, Campus de Gambelas, 8000-062 Faro, Portugal
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Le Bail P, Rondeau C, Buléon A. Structural investigation of amylose complexes with small ligands: helical conformation, crystalline structure and thermostability. Int J Biol Macromol 2005; 35:1-7. [PMID: 15769508 DOI: 10.1016/j.ijbiomac.2004.09.001] [Citation(s) in RCA: 117] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/13/2004] [Indexed: 11/26/2022]
Abstract
Crystalline amylose complexes were prepared with decanal, 1-butanol, menthone and alpha-naphtol. Their crystalline structure and the related helical conformation, determined by wide angle X-ray diffraction (WAXD) and 13C CPMAS solid state NMR, were assigned to V6I, V6II, V6III and V8 types, respectively. It was possible to propose some hypotheses on the possible nature of interactions and especially intra-/inter-helical inclusion. Some shifts in the NMR C1 carbon signals were attributed to the presence of ligand in specific sites inside the structure for a same type of V6 helical conformation. Moreover, the crystallinity and polymorphic changes induced by desorption/rehydration were studied. A general increase of the carbon resonances sharpness upon rehydration has been observed, but also a V6II-V6I transition when decreasing the water content. Differential scanning calorimetry (DSC) experiments were also performed to approach the thermostability of the four types of complex and also the way they form again after melting/cooling sequences.
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Affiliation(s)
- P Le Bail
- Unité de Physicochimie des Macromolécules, Institut National de la Recherche Agronomique, BP 71627, 44316 Nantes, Cedex 03, France.
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Girardeau TE, Zhao T, Leisen J, Beckham HW, Bucknall DG. Solid Inclusion Complexes of α-Cyclodextrin and Perdeuterated Poly(oxyethylene). Macromolecules 2005. [DOI: 10.1021/ma048756w] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Tom E. Girardeau
- School of Polymer, Textile and Fiber Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0295
| | - Tiejun Zhao
- School of Polymer, Textile and Fiber Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0295
| | - Johannes Leisen
- School of Polymer, Textile and Fiber Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0295
| | - Haskell W. Beckham
- School of Polymer, Textile and Fiber Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0295
| | - David G. Bucknall
- Department of Materials, Oxford University, Oxford, Parks Road, Oxford, OX1 3PH, U.K
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Cunha-Silva L, Teixeira-Dias JJC. Solid-state inclusion compounds of small amphiphilic molecules (CnEm) in β-cyclodextrin: a study at defined relative humidities. NEW J CHEM 2005. [DOI: 10.1039/b507215h] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Rondeau-Mouro C, Le Bail P, Buléon A. Structural investigation of amylose complexes with small ligands: inter- or intra-helical associations? Int J Biol Macromol 2004; 34:309-15. [PMID: 15556233 DOI: 10.1016/j.ijbiomac.2004.09.002] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/13/2004] [Indexed: 11/25/2022]
Abstract
Highly crystalline amylose complexes with menthone (1) and linalool (2) were analysed by wide-angle X-ray diffraction and solid-state nuclear magnetic resonance (NMR). The complexes, after partial water desorption in a controlled atmosphere (aw=0.75), displayed a typical V-isopropanol structure, showing the presence of ligand inside or between the helices in the crystalline domains. Sequential washing of the powdered complexes with ethanol before and after desorption permitted probing the intra- and inter-helical inclusions. High resolution magic angle spinning (HRMAS) recordings were used to compare the chemical shifts of free and bound aroma which allowed a proposal that some hydrogen bonding is involved in the amylose complexing. Moreover, it showed that free aroma was completely removed by ethanol washing. Using cross polarization magic angle spinning (CPMAS) and X-ray scattering experiments, it was demonstrated that the V-isopropanol type was retained for linalool whatever the treatment used. On the contrary, the measurement shifts toward the V-6I amylose hydrate (V-h) type for menthone after ethanol washing before the desorption step, reflecting the disappearance of inter-helical associations between menthone and amylose. The stability of the complex prepared with linalool shows that this ligand is more strongly associated to amylose helices. The discrepancies observed in the chemical shifts attributed to carbons C1 and C4 in CPMAS spectra of V-isopropanol and V-h forms could be attributed either to a deformation of the single helix (with possible inclusion of the ligand inside) or to the presence of the ligand between helices (only water molecules are present in the V-h form).
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Affiliation(s)
- C Rondeau-Mouro
- Unité de Physico-Chimie des Macromolécules, Institut National de la Recherche Agronomique, rue de la Géraudière, BP 71627, 44316 Nantes Cedex 03, France.
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34
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Sletmoen M, Maurstad G, Sikorski P, Paulsen BS, Stokke BT. Characterisation of bacterial polysaccharides: steps towards single-molecular studies. Carbohydr Res 2004; 338:2459-75. [PMID: 14670709 DOI: 10.1016/j.carres.2003.07.007] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Techniques used in studies of polysaccharides, including chemical composition, linkage pattern, and higher order structures are in constant development. They provide information necessary for understanding of the polysaccharide properties and functions. Here, recent advancements in studies of the polysaccharides at the single-molecule level are highlighted. Over the last few years, single-molecule techniques such as force spectroscopy have improved in sensitivity and can today be used to detect forces in the pN range. In addition, these techniques can be used to investigate properties of single molecules close to physiological conditions. The challenges in the interpretation of the observations are aided by control experiments using well-characterised polysaccharides and by data provided by complementary methods. This field is expected to have increasing impact on the further advancement of the molecular understanding of the role of polysaccharides in various biological processes such as recognition and cell adhesion.
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Affiliation(s)
- Marit Sletmoen
- Biophysics and Medical Technology, Department of Physics, The Norwegian University of Science and Technology, NTNU, NO-7491 Trondheim, Norway
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35
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36
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Braga SS, Sá Ferreira RA, Gonçalves IS, Pillinger M, Rocha J, Teixeira-Dias JJC, Carlos LD. Synthesis, Characterization, and Luminescence of β-Cyclodextrin Inclusion Compounds Containing Europium(III) and Gadolinium(III) Tris(β-diketonates). J Phys Chem B 2002. [DOI: 10.1021/jp0204004] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Susana S. Braga
- Department of Chemistry and Department of Physics, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal
| | - Rute A. Sá Ferreira
- Department of Chemistry and Department of Physics, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal
| | - Isabel S. Gonçalves
- Department of Chemistry and Department of Physics, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal
| | - Martyn Pillinger
- Department of Chemistry and Department of Physics, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal
| | - João Rocha
- Department of Chemistry and Department of Physics, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal
| | - José J. C. Teixeira-Dias
- Department of Chemistry and Department of Physics, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal
| | - Luís D. Carlos
- Department of Chemistry and Department of Physics, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal
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37
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Synthesis and characterization of the inclusion compound of a methyltrioxorhenium(VII) adduct of 4-ferrocenylpyridine with β-cyclodextrin. J Organomet Chem 2002. [DOI: 10.1016/s0022-328x(02)01635-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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38
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Tang HR, Belton PS. Molecular dynamics of polycrystalline cellobiose studied by solid-state NMR. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2002; 21:117-133. [PMID: 12199355 DOI: 10.1006/snmr.2002.0052] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Molecular motions of polycrystalline cellobiose have been investigated by measuring proton spin-lattice relaxation times, T1 and T1rho, and the second moment, M2, in both protonated and D2O exchanged forms over the temperature range 120-380 K. T1 relaxation is dominated by the motions of hydroxyl groups between 150 and 380 K, characterised by an activation energy of about 8.74 kJ/mol, whereas T1rho relaxation is driven by the motions of the same groups between 120 and 300 K. T1rho results suggest that hydroxyl groups have a distribution of dynamics. Motion of methylene groups was detected in the second-moment experiments at about 350 K, characterised by activation energy of about 40 kJ/mol. Consideration of the calculated and observed rigid-lattice second moments suggests that the reported X-ray data are incorrect for the inter-proton distance on C6'. 13C CPMAS spectra of both protonated and deuterated cellobiose have also been measured. Spectra of the deuterated material showed the existence of a second crystalline form in addition to the normal form.
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Affiliation(s)
- H R Tang
- Institute of Food Research, Norwich Research Park, Colney, UK.
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39
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Experimental and theoretical study of the interaction of molybdenocene dichloride (Cp2MoCl2) with β-cyclodextrin. J Organomet Chem 2001. [DOI: 10.1016/s0022-328x(01)00836-1] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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40
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Lima S, Gonçalves IS, Ribeiro-Claro P, Pillinger M, Lopes AD, Ferreira P, Teixeira-Dias JJC, Rocha J, Romão CC. Interactions of Cationic and Neutral Molybdenum Complexes with β-Cyclodextrin Host Molecules. Organometallics 2001. [DOI: 10.1021/om001088s] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Sérgio Lima
- Department of Chemistry, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal, Química-Física Molecular, Faculdade de Ciências e Tecnologia, Universidade de Coimbra, 3004-353 Coimbra, Portugal, and Instituto de Tecnologia Química e Biológica, Quinta do Marquês, EAN, Apt 127, 2781-901 Oeiras, Portugal
| | - Isabel S. Gonçalves
- Department of Chemistry, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal, Química-Física Molecular, Faculdade de Ciências e Tecnologia, Universidade de Coimbra, 3004-353 Coimbra, Portugal, and Instituto de Tecnologia Química e Biológica, Quinta do Marquês, EAN, Apt 127, 2781-901 Oeiras, Portugal
| | - Paulo Ribeiro-Claro
- Department of Chemistry, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal, Química-Física Molecular, Faculdade de Ciências e Tecnologia, Universidade de Coimbra, 3004-353 Coimbra, Portugal, and Instituto de Tecnologia Química e Biológica, Quinta do Marquês, EAN, Apt 127, 2781-901 Oeiras, Portugal
| | - Martyn Pillinger
- Department of Chemistry, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal, Química-Física Molecular, Faculdade de Ciências e Tecnologia, Universidade de Coimbra, 3004-353 Coimbra, Portugal, and Instituto de Tecnologia Química e Biológica, Quinta do Marquês, EAN, Apt 127, 2781-901 Oeiras, Portugal
| | - André D. Lopes
- Department of Chemistry, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal, Química-Física Molecular, Faculdade de Ciências e Tecnologia, Universidade de Coimbra, 3004-353 Coimbra, Portugal, and Instituto de Tecnologia Química e Biológica, Quinta do Marquês, EAN, Apt 127, 2781-901 Oeiras, Portugal
| | - Paula Ferreira
- Department of Chemistry, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal, Química-Física Molecular, Faculdade de Ciências e Tecnologia, Universidade de Coimbra, 3004-353 Coimbra, Portugal, and Instituto de Tecnologia Química e Biológica, Quinta do Marquês, EAN, Apt 127, 2781-901 Oeiras, Portugal
| | - José J. C. Teixeira-Dias
- Department of Chemistry, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal, Química-Física Molecular, Faculdade de Ciências e Tecnologia, Universidade de Coimbra, 3004-353 Coimbra, Portugal, and Instituto de Tecnologia Química e Biológica, Quinta do Marquês, EAN, Apt 127, 2781-901 Oeiras, Portugal
| | - João Rocha
- Department of Chemistry, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal, Química-Física Molecular, Faculdade de Ciências e Tecnologia, Universidade de Coimbra, 3004-353 Coimbra, Portugal, and Instituto de Tecnologia Química e Biológica, Quinta do Marquês, EAN, Apt 127, 2781-901 Oeiras, Portugal
| | - Carlos C. Romão
- Department of Chemistry, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal, Química-Física Molecular, Faculdade de Ciências e Tecnologia, Universidade de Coimbra, 3004-353 Coimbra, Portugal, and Instituto de Tecnologia Química e Biológica, Quinta do Marquês, EAN, Apt 127, 2781-901 Oeiras, Portugal
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41
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Okada M, Kamachi M, Harada A. Preparation and Characterization of Inclusion Complexes between Methylated Cyclodextrins and Poly(tetrahydrofuran). Macromolecules 1999. [DOI: 10.1021/ma990806n] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Miyuko Okada
- Graduate School of Science, Osaka University,Toyonaka, Osaka 560-0043, Japan
| | - Mikiharu Kamachi
- Graduate School of Science, Osaka University,Toyonaka, Osaka 560-0043, Japan
| | - Akira Harada
- Graduate School of Science, Osaka University,Toyonaka, Osaka 560-0043, Japan
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42
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Separation and NMR structural characterisation of singly branched α-dextrins which differ in the location of the branch point. Carbohydr Res 1998. [DOI: 10.1016/s0008-6215(98)00241-9] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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43
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Zhang P, Klymachyov AN, Brown S, Ellington JG, Grandinetti PJ. Solid-state 13C NMR investigations of the glycosidic linkage in alpha-alpha' trehalose. SOLID STATE NUCLEAR MAGNETIC RESONANCE 1998; 12:221-225. [PMID: 9800267 DOI: 10.1016/s0926-2040(98)00069-1] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The sugar trehalose is known to play a central role in the desiccation tolerance of many organisms. Essential to trehalose's role are its glass forming abilities and ability to directly interact with lipid molecules. Detailed information on the structure and dynamics of glassy trehalose and its interactions with lipids, however, have been elusive. We have used solid-state NMR and ab initio quantum mechanical methods (Gaussian 94) in order to characterize the possible molecular conformations of trehalose. Using a simplified structure (2-(tetrahydropyran-2-yloxy) tetrahydropyran) as a model we have calculated the energy and 13C magnetic shielding parameters as a function of the two glycosidic torsion angles. Combining ab initio derived maps and using the 13C lineshape as constraints we were able to construct the torsion angle distribution map for alpha-alpha' trehalose. We believe measurements of 13C isotropic chemical shift and other solid-state NMR tensor parameter distributions in combination with ab initio methods can prove useful in identifying sources of structural disorder in glassy trehalose. By monitoring these structural distributions new information about the membrane surface associative properties of trehalose and other sugars should be accessible.
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Affiliation(s)
- P Zhang
- Department of Chemistry, Ohio State University, Columbus 43210-1173, USA
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44
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Polysaccharides and biological systems. ACTA ACUST UNITED AC 1998. [DOI: 10.1016/s0167-6881(98)80032-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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45
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Witkowski S, Wałejko P, Wawer I. 13C CP MAS NMR study of 6-O-(beta-D-glucopyranosyl)- and 6-O-(beta-D-mannopyranosyl)-d-alpha-tocopherols. SOLID STATE NUCLEAR MAGNETIC RESONANCE 1998; 10:123-128. [PMID: 9550340 DOI: 10.1016/s0926-2040(97)00084-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
13C NMR CP MAS data for three glycosyl alpha-tocopherol derivatives are reported. The values of delta = delta(solution) - delta(solid state) provided information about rigid and conformationally flexible fragments of alpha-tocopherol molecule and the sugar moieties.
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Affiliation(s)
- S Witkowski
- University of Warsaw Bialystok Branch, Department of Chemistry, Bialystok, Poland
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46
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Hricovíni M, Malkina OL, Bízik F, Nagy LT, Malkin VG. Calculation of NMR Chemical Shifts and Spin−Spin Coupling Constants in the Monosaccharide Methyl-β-d-xylopyranoside Using a Density Functional Theory Approach. J Phys Chem A 1997. [DOI: 10.1021/jp972071z] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- M. Hricovíni
- Institute of Chemistry, Computing Center, Institute of Virology, and Institute of Inorganic Chemistry, Slovak Academy of Sciences, SK-84236 Bratislava, Slovakia
| | - O. L. Malkina
- Institute of Chemistry, Computing Center, Institute of Virology, and Institute of Inorganic Chemistry, Slovak Academy of Sciences, SK-84236 Bratislava, Slovakia
| | - F. Bízik
- Institute of Chemistry, Computing Center, Institute of Virology, and Institute of Inorganic Chemistry, Slovak Academy of Sciences, SK-84236 Bratislava, Slovakia
| | - L. Turi Nagy
- Institute of Chemistry, Computing Center, Institute of Virology, and Institute of Inorganic Chemistry, Slovak Academy of Sciences, SK-84236 Bratislava, Slovakia
| | - V. G. Malkin
- Institute of Chemistry, Computing Center, Institute of Virology, and Institute of Inorganic Chemistry, Slovak Academy of Sciences, SK-84236 Bratislava, Slovakia
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47
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Temeriusz A, Piekarska-Bartoszewicz B, Wawer I. Synthesis and characterization by 13C-CP-MAS- and high resolution 1H-, 13C-NMR of new ureido sugars, derivatives of methyl 2-amino-2-deoxy-β-d-glucopyranose and dipeptides. Carbohydr Res 1997. [DOI: 10.1016/s0008-6215(97)00236-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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48
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Gattuso G, Menzer S, Nepogodiev SA, Stoddart JF, Williams DJ. Kohlenhydrat-Nanoröhren. Angew Chem Int Ed Engl 1997. [DOI: 10.1002/ange.19971091353] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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49
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Bruzik KS, Nyholm PG. NMR study of the conformation of galactocerebroside in bilayers and solution: galactose reorientation during the metastable-stable gel transition. Biochemistry 1997; 36:566-75. [PMID: 9012672 DOI: 10.1021/bi962204r] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Conformations of two types of bovine brain cerebroside containing normal and alpha-hydroxy-fatty acids (NFA-CER and HFA-CER, respectively) in solution and in bilayers were investigated using 1H and 13C NMR in solution and in the solid state. The analysis of vicinal 1H-1H coupling constants and NOE measurements in solution indicated that in both cerebrosides the predominant conformation about the O1-C1, C1-C2, and C2-C3 bonds is ap/-sc/ap, respectively. The remarkable similarity in the 13C NMR chemical shifts in solution and in hydrated liquid-crystalline bilayers indicated that both cerebrosides in bilayers assume conformation essentially identical to those in solution. The obtained 13C NMR spectra in solution were used as a reference for comparison with the variable-temperature 13C CP-MAS NMR spectra in the metastable and stable gel phases. The lack of chemical shift changes of polar carbon atoms upon cooling the HFA-CER bilayers below the Tm strongly suggests that the liquid-crystalline-metastable gel transition is not associated with a conformational change of the head group. The observed line broadening can be interpreted in terms of the hydrocarbon chain crystallization and slow dynamics of the head group in the metastable phase. On the other hand, the relaxation of the metastable gel phase of HFA-CER caused profound changes in the 13C spectra, primarily of the signals of the galactose C1, the ceramide C2, C4, and C5, and the carbonyl group. These changes are interpreted using the known dependence of the chemical shifts of anomeric carbon on the conformation about the O1-C1 bond to suggest that the gel phase relaxation involves a significant reorientation of the galactose moiety caused by a change in the rotation of the O1-C1 bond from the ap to -sc conformer. Similar changes of chemical shifts were observed in the case of NFA-CER during the transition from the liquid-crystalline phase to the stable gel phase.
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Affiliation(s)
- K S Bruzik
- Department of Medicinal Chemistry and Pharmacognosy (m/c 781), University of Illinois at Chicago 60612, USA
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50
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Sfihi H, Legrand A, Doussot J, Guy A. Solid-state 13C NMR study of β-cyclodextrin/substituted aromatic ketone complexes: evidence for two kinds of complexation of the guest molecules. Colloids Surf A Physicochem Eng Asp 1996. [DOI: 10.1016/0927-7757(96)03614-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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