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Rutenberg R, Leitus G, Fallik E, Poverenov E. Discovery of a non classic host guest complexation mode in a β-cyclodextrin/propionic acid model. Chem Commun (Camb) 2016; 52:2565-8. [PMID: 26744749 DOI: 10.1039/c5cc09676f] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A non-classic complexation mode was discovered upon spectroscopic, thermodynamic, crystallographic and computational studies of a β-cyclodextrin/propionic acid complex. A "fully immersed" complexation phenomenon, where both the guest's hydrophobic and polar moieties are located inside the host and are stabilized by it, was found and calculated as the most favorable configuration.
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Affiliation(s)
- R Rutenberg
- Institute of Biochemistry, Food Sciences and Nutrition, Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot 76100, Israel
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2
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Attoui-Yahia O, Khatmi D, Kraim K, Ferkous F. Hydrogen bonding investigation in Pyridoxine/β-cyclodextrin complex based on QTAIM and NBO approaches. J Taiwan Inst Chem Eng 2015. [DOI: 10.1016/j.jtice.2014.09.028] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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3
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Aggregation property of glycyrrhizic acid and its interaction with cyclodextrins analyzed by dynamic light scattering, isothermal titration calorimetry, and NMR. Carbohydr Res 2014; 392:25-30. [DOI: 10.1016/j.carres.2014.04.017] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Revised: 04/21/2014] [Accepted: 04/22/2014] [Indexed: 11/18/2022]
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4
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Pacioni NL, Pierini AB, Veglia AV. Structural characterization of N-methylcarbamate: β-cyclodextrin complexes by experimental methods and molecular dynamics simulations. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2013; 103:319-324. [PMID: 23261629 DOI: 10.1016/j.saa.2012.11.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2012] [Revised: 10/24/2012] [Accepted: 11/04/2012] [Indexed: 06/01/2023]
Abstract
Detailed insights regarding the inclusion process between β-cyclodextrin and the N-methylcarbamates insecticides like Bendiocarb, Carbaryl, Carbofuran and Promecarb, are proposed in bases of experimental and computational methods. The results from Fourier transform infrared spectroscopy, differential scanning calorimetry, induced circular dichroism and molecular dynamics indicate that only in the case of Promecarb the interaction with the macrocycle is produced by the alkyl rest of the molecule. In all other cases the aromatic moiety is the part of the insecticide that is partially included in the cavity of β-cyclodextrin.
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Affiliation(s)
- Natalia L Pacioni
- Instituto de Investigaciones en Físico Química de Córdoba, Departamento de Química Orgánica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, 5000 Córdoba, Argentina
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5
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Theoretical investigation study based on PM3MM and ONIOM2 calculations of β-Cyclodextrin complexes with diphenylamine. J INCL PHENOM MACRO 2012. [DOI: 10.1007/s10847-012-0266-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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6
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Fatiha M, Leila L, Eddine KD, Leila N. Computational investigation of enol/keto chloramphenicol with β-cyclodextrin. J INCL PHENOM MACRO 2012. [DOI: 10.1007/s10847-012-0262-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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7
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Bensouilah N, Abdaoui M. Inclusion complex of N-nitroso, N-(2-chloroethyl), N′, N′-dibenzylsulfamid with β-Cyclodextrin: Fluorescence and molecular modeling. CR CHIM 2012. [DOI: 10.1016/j.crci.2012.09.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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8
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Fatiha M, Leila L, Leila N, Eddine KD. Theoretical study of the inclusion processes of ethyl p-hydroxybenzoate with β-cyclodextrin: PM3MM and ONIOM2 calculations. J Taiwan Inst Chem Eng 2012. [DOI: 10.1016/j.jtice.2012.07.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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9
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Fatiha M, Leila L, Leila N, Eddine KD. Computational study on the encapsulation of ethylparaben into β-cyclodextrin. J INCL PHENOM MACRO 2012. [DOI: 10.1007/s10847-012-0209-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Ali SM, Khan S, Crowyn G. Structure determination of fexofenadine-α-cyclodextrin complex by quantitative 2D ROESY analysis and molecular mechanics studies. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2012; 50:299-304. [PMID: 22416034 DOI: 10.1002/mrc.3807] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2011] [Revised: 02/05/2012] [Accepted: 02/08/2012] [Indexed: 05/31/2023]
Abstract
Complexation of fexofenadine with α-cyclodextrin in aqueous medium was studied. The stoichiometry of the resulting inclusion complex was determined by (1) H NMR titration data. 2D ROESY data provided the evidence of formation of the complex by entry of the phenyl ring into the α-cyclodextrin cavity probably from wider opening. Determination of relative peak intensities of intermolecular cross-peaks for the most stable complexes obtained by molecular mechanics (MM2) studies and from 2D ROESY spectral data confirmed the presence of only one complex in solution that has been fully characterized.
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Affiliation(s)
- Syed Mashhood Ali
- Department of Chemistry, Aligarh Muslim University, Aligarh, 202002, Uttar Pradesh, India.
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Fielding L, McKellar SC, Florence AJ. Precision studies in supramolecular chemistry: a 1H NMR study of hydroxymethoxyacetophenone/β-cyclodextrin complexes. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2011; 49:405-412. [PMID: 21547943 DOI: 10.1002/mrc.2762] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2011] [Revised: 03/11/2011] [Accepted: 03/14/2011] [Indexed: 05/30/2023]
Abstract
The association constants for the interactions of 2-hydroxy-4-methoxyacetophenone, 2-hydroxy-5-methoxyacetophenone, 2-hydroxy-6-methoxyacetophenone, 3-hydroxy-4-methoxyacetophenone and 4-hydroxy-3-methoxyacetophenone with β-cyclodextrin in water were measured by (1)H NMR and by isothermal titration calorimetry. Very good agreement was obtained between the different methods. The errors associated with the NMR method for measuring mM binding affinities were estimated to be 10-30%, and by isothermal titration calorimetry, 10-20%. Rotating frame nuclear Overhauser effect spectroscopy studies show that the solution phase host-guest complexes formed by β-cyclodextrin with these hydroxymethoxyacetophenone derivatives are not structurally well defined but that the hydroxymethoxyacetophenone derivatives are mostly associated with the narrow primary hydroxyl rim.
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Affiliation(s)
- Lee Fielding
- Department of Medicinal Chemistry, MSD, Newhouse ML1 5SH, UK.
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Leila N, Sakina H, Bouhadiba A, Fatiha M, Leila L. Molecular modeling investigation of para-nitrobenzoic acid interaction in β-cyclodextrin. J Mol Liq 2011. [DOI: 10.1016/j.molliq.2011.02.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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13
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Fatiha M, Khatmi D, Largate L. Theoretical approach in the study of the inclusion processes of sulconazole with β-cyclodextrin. J Mol Liq 2010. [DOI: 10.1016/j.molliq.2010.03.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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14
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Madi F, Khatmi D, Dhaoui N, Bouzitouna A, Abdaoui M, Boucekkine A. Molecular model of CENS piperidine β-CD inclusion complex: DFT study. CR CHIM 2009. [DOI: 10.1016/j.crci.2009.06.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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15
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Association mechanism of S-dinitrophenyl glutathione with two glutathione peroxidase mimics: 2, 2 cent-ditelluro- and 2, 2 cent-diseleno-bridged b-cyclodextrins. Molecules 2009; 14:904-16. [PMID: 19255549 PMCID: PMC6253948 DOI: 10.3390/molecules14030904] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2008] [Revised: 12/17/2008] [Accepted: 12/23/2008] [Indexed: 11/23/2022] Open
Abstract
Complex formation of the glutathione peroxidase mimics 2,2′-ditelluro-bridged β-cyclodextrin (1) and 2,2′-diseleno-bridged β-cyclodextrin (2), with S-substituted dinitrophenyl glutathione (3) were determined by ultraviolet-visible (UV-Vis) absorption spectroscopy in phosphate buffer (pH 7.4) and 1H-NMR spectroscopy. Molecular mechanics (MM2) modeling calculations were used to deduce a three-dimensional model for each complex. The dinitrophenyl (DNP) group of 3 appears to penetrate the cavity of β-cyclodextrin (β-CD) or 1, but it is located between the two secondary rims of 2. The complexes’ stability constants (Ks) from 19 to 37 °C, Gibbs free energy changes (ΔG°), ΔH° and TΔS° for 1:1 complexes of β-CD, 1 and 2 with ligand 3 as obtained from UV-Vis spectra were compared. The binding of 3 by the three cyclodextrin hosts generally decreased in the order of 1>2>β-CD. The binding ability of 3 by β-CD, 1 and 2 was discussed with regard to the size/shape-fit concept, the induced-fit interaction, and the cooperative interaction of the dual hydrophobic cavities. The binding ability of 1>2 indicated that the length of linkage between two cyclodextrin units plays a crucial role in the interaction with 3.
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Cruz JR, Becker BA, Morris KF, Larive CK. NMR characterization of the host-guest inclusion complex between beta-cyclodextrin and doxepin. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2008; 46:838-845. [PMID: 18615634 DOI: 10.1002/mrc.2267] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The interaction between doxepin, a member of the tricyclic antidepressant (TCA) class of drugs, with beta-cyclodextrin (beta-CD) was investigated using NMR. Several TCAs have been reported to form a complex with beta-CD having 1:1 stoichiometry. Previous results from UV-visible spectroscopy, fluorescence measurements, and molecular modeling indicated that for imipramine, desipramine, and amitriptyline, the TCA aliphatic tail is included in the cyclodextrin cavity with apparently no interaction of the tricyclic ring. An alternative view of the doxepin-beta-CD complex is presented in this work using analysis of complexation-induced chemical shifts (CICSs), the method of continuous variation (Job's analysis), and analysis of ROESY spectra. The Job's plot derived from the NMR spectral data confirms that the complex formed has 1:1 stoichiometry. The largest changes in the CICS data were observed for the aromatic protons of one of the doxepin rings, with much smaller chemical shift changes observed for the protons of the other aromatic ring and the doxepin tail. Perhaps the most significant evidence for inclusion of the doxepin tricyclic ring is the strong ROESY cross peaks between the doxepin aromatic resonances and the protons located inside the beta-CD cavity. Changes in the doxepin (1)H NMR spectrum and the behavior of ROESY exchange cross peaks suggest that inclusion complex formation decreases the rate of internal motions of doxepin.
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Affiliation(s)
- Jennifer R Cruz
- Department of Chemistry, University of California, Riverside, CA 92521, USA
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17
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Takenaka Y, Nakashima H, Yoshida N. Fluorescent amino-β-cyclodextrin derivative as a receptor for various types of alcohols having cyclic and macrocyclic rings. J Mol Struct 2007. [DOI: 10.1016/j.molstruc.2007.02.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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18
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NMR spectroscopic study of the inclusion complex of desloratadine with β-cyclodextrin in solution. J INCL PHENOM MACRO 2007. [DOI: 10.1007/s10847-007-9335-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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19
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Mashhood Ali S, Maheshwari A, Inder Fozdar B. 1H NMR spectroscopic study of complexation of citalopram with beta-cyclodextrin in aqueous solution. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2007; 45:253-6. [PMID: 17290386 DOI: 10.1002/mrc.1958] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
(1)H NMR spectroscopic study of citalopram (CT) in the absence as well as in the presence of beta-cyclodextrin (beta-CD) in aqueous solution revealed the formation of four 1:1 beta-CD-CT inclusion complexes. The stoichiometry of the complexes was determined by the continuous variation (Job) method, which was further confirmed by Scott's method. The binding constants (K(R) and K(R, S)) were calculated using Scott's method. The structures of all the complexes have been proposed as shown in the diagrams. All the CT proton resonances showed splitting in the presence of beta-CD, owing to chiral discrimination by the beta-CD, between the two enantiomers. The chiral discrimination appears to be due to different modes of binding of the R- and S-CT in the complexes involving a CN-containing aromatic ring.
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Affiliation(s)
- Syed Mashhood Ali
- Department of Chemistry, Aligarh Muslim University, Aligarh 202002 (UP), India.
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20
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Ali SM, Upadhyay SK, Maheshwari A, Koketsu M. Complexation of Fluvastatin Sodium with β-Cyclodextrin: NMR Spectroscopic Study in Solution. J INCL PHENOM MACRO 2006. [DOI: 10.1007/s10847-006-9099-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Hromadová M, Pospísil L, Fanelli N, Giannarelli S. Models of pesticides inside cavities of molecular dimensions. A role of the guest inclusion in the dechlorination process. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2005; 21:1923-1930. [PMID: 15723490 DOI: 10.1021/la048021k] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The reduction mechanism of the pesticide vinclozoline (3-(3,5-dichlorophenyl)-5-methyl-5-vinyl-1,3-oxazolidine-2,4-dione) was studied in nonaqueous solvents in the confined environment of a cyclodextrin (CD) cavity. The effect of the cavity dimensions on the mechanism of the redox process was evaluated using glucose as a reference and using three cyclodextrin molecules of different cavity sizes, namely, alphaCD, betaCD, and gammaCD. In the absence of CD the main reduction product of vinclozoline in the first reduction step is dichloroaniline. An addition of glucose leads to a quantitative change of mechanism with 10 products in total. Addition of CD, however, leads exclusively to dechlorination of the phenyl ring. The degree of dechlorination depends strongly on the choice of cyclodextrin molecule. The importance of the complex formation equilibria in the change of the mechanism is supported by a series of semiempirical AM1 quantum-mechanical calculations. Very good correlation (correlation coefficient 0.995) was obtained between the complex stabilization energy of the inclusion complex and the degree of pesticide dechlorination. Additionally, we were able to show that the complexes are stabilized by the formation of intermolecular hydrogen bonds between the host and guest species. CD molecules do not simply act as proton donors in a nonaqueous environment, but also protect parts of the molecule included within the cavity and steer the degradation process toward fewer products.
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Affiliation(s)
- Magdaléna Hromadová
- J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, Dolejskova 3, 18223 Prague, Czech Republic
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Perdomo-López I, Rodríguez-Pérez AI, Yzquierdo-Peiró JM, White A, Estrada EG, Villa TG, Torres-Labandeira JJ. Effect of cyclodextrins on the solubility and antimycotic activity of sertaconazole: experimental and computational studies. J Pharm Sci 2002; 91:2408-15. [PMID: 12379926 DOI: 10.1002/jps.10237] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
This study investigated the effects of the complexation of sertaconazole nitrate with different cyclodextrin (CD) derivatives (alpha-CD, beta-CD, gamma-CD, hydroxypropyl-beta-CD, and hydroxypropyl-gamma-CD) on the aqueous solubility and antimycotic activity of the drug. Phase solubility studies indicated that the solubility of sertaconazole in enzyme-free simulated gastric- and enzyme-free simulated enteric fluids was significantly increased in the presence of cyclodextrins. The observed order of solubility increasing effect was: gamma-CD > HPgamma-CD > HPbeta-CD > beta-CD > alpha-CD. Solid-state sertaconazole-cyclodextrin complexes were prepared by freeze drying, and characterized by X-ray powder difractometry, differential scanning calorimetry (DSC), and infrared spectroscopy (FTIR). Freeze-dried complexes showed markedly higher solubility than both physical mixtures and sertaconazole alone. The antimycotic activities of sertaconazole-cyclodextrin complexes in solution were evaluated by inhibition zone assays with Candida albicans. The activity ranking agrees with the solubility ranking observed for these complexes, with the gamma-CD-sertaconazole complex showing the strongest antimycotic activity. Finally, molecular modeling studies were carried out using the MM2 force field method, for complexes in vacuum and in water. This enable indentification of the preferred orientation of sertaconazole in the gamma-CD cavity and of the main structural features responsible for the enhancement of its solubility and antimycotic activity.
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Affiliation(s)
- I Perdomo-López
- Departamento de Farmacia e Tecnoloxía Farmacéutica, Facultade de Farmacia, Universidade de Santiago de Compostela, Campus Sur, E-15782 Santiago de Compostela, Spain
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25
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α- and β-cyclodextrin complexes with n-alkyl carboxylic acids and n-alkyl p-hydroxy benzoates. A molecular mechanics study of 1:1 and 1:2 associations. ACTA ACUST UNITED AC 2002. [DOI: 10.1016/s0166-1280(02)00393-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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26
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Zborowski K, Zuchowski G. Enantioselective chromatography of alkyl derivatives of 5-ethyl-5-phenyl-2-thiobarbituric acid studied by semiempirical AM1 method. Chirality 2002; 14:632-7. [PMID: 12125032 DOI: 10.1002/chir.10123] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Complexation of alkyl derivatives of 5-ethyl-5-phenyl-2-thiobarbituric acid (2-thiophenobarbital) enantiomers by beta-cyclodextrin was investigated by the AM1 method. The inclusion complexes of beta-cyclodextrin with neutral and anionic forms of these enantiomers have been modeled and energetically optimized. The chiral discrimination of enantiomers was analyzed in terms of differences in the interaction energies. The calculated interaction energies between each enantiomer of the investigated 2-thiobarbiturates and beta-cyclodextrin confirm the ability of beta-cyclodextrin to act as a mobile phase additive in reversed-phase HPLC to separate enantiomers by liquid chromatography and rationalize their order of elution.
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Echezarreta-López MM, Perdomo-López I, Estrada E, Vila-Jato JL, Torres-Labandeira JJ. Utility of nuclear magnetic resonance spectroscopy to characterize the structure of dexamethasone sodium phosphate inclusion complexes with cyclodextrins in solution and to analyze potential competitive effects. J Pharm Sci 2002; 91:1536-47. [PMID: 12115852 DOI: 10.1002/jps.10145] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The interaction between dexamethasone sodium phosphate (DSP) and four cyclodextrin (CyD) derivatives [2,6-di-O-beta-cyclodextrin (DIMEB), gamma-cyclodextrin (gamma-CyD), and hydroxypropyl-beta-cyclodextrin with either 2.7 or 4.6 degrees of substitution (HPbetaCyD 2.7 and HPbetaCyD 4.6, respectively)] was investigated by proton nuclear magnetic resonance spectroscopy (1H NMR). The data suggested the formation of inclusion complexes in solution in which B and C rings of the molecule are located inside the cavity. Nevertheless, the structure, in terms of depth within CyD, depends on the derivative considered. Molecular mechanics calculations of DSP complexes with DIMEB and gamma-CyD support the NMR results. The potential displacement of DSP from the CyD cavity by usual ophthalmic drugs (e.g., polymyxin B, trimethoprim, and benzalkonium chloride) was determined by NMR. The technique has been found useful to analyze this problem in pharmaceutical preparations.
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Affiliation(s)
- M M Echezarreta-López
- Departamento de Farmacia e Tecnoloxía Farmacéutica, Facultade de Farmacia, Universidade de Santiago de Compostela, Campus Universitario Sur, E-15782 Santiago de Compostela, Spain
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Carofiglio T, Fornasier R, Jicsinszky L, Saielli G, Tonellato U, Vetta R. Capillary Electrophoresis, ROESY NMR and Molecular Modelling Study of the Inclusion Complex β-Cyclodextrin/Lipoic Acid. European J Org Chem 2002. [DOI: 10.1002/1099-0690(200204)2002:7<1191::aid-ejoc1191>3.0.co;2-i] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Estrada E, Perdomo-López I, Torres-Labandeira JJ. Combination of 2D-, 3D-connectivity and quantum chemical descriptors in QSPR. Complexation of alpha- and beta-cyclodextrin with benzene derivatives. JOURNAL OF CHEMICAL INFORMATION AND COMPUTER SCIENCES 2001; 41:1561-8. [PMID: 11749583 DOI: 10.1021/ci0100402] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Quantitative models are found to describe the complexation of alpha- and beta-cyclodextrin with mono- and 1,4-disubstituted benzene derivatives by using combinations of 2D-, 3D-connectivity and quantum chemical molecular descriptors. The association constants (K(a)) for the inclusion complexation of cyclodextrins and benzene derivatives are calculated by the models found with a high degree of precision. These models also permit the interpretation of the driving forces of such complexation processes. In the case of the complexation of alpha-cyclodextrin with benzene derivatives these driving forces are mainly the electronic repulsion between frontier orbitals of the host and guest molecules. However, the complexation of beta-cyclodextrin with benzene derivatives is controlled by topological and topographic parameters indicating the relevance of the van der Waals and hydrophobic interactions. We also carried out molecular modeling studies showing that for alpha-cyclodextrin complexes the benzene ring is outside the cavity of the cyclodextrin, while in beta-cyclodextrin they penetrate deeply into the apolar and hydrophobic cavity of the host, which explain the differences in the driving forces for both complexation processes.
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Affiliation(s)
- E Estrada
- Faculty of Pharmacy, Department of Organic Chemistry, University of Santiago de Compostela, 15706 Santiago de Compostela, Spain.
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Pose-Vilarnovo B, Perdomo-López I, Echezarreta-López M, Schroth-Pardo P, Estrada E, Torres-Labandeira JJ. Improvement of water solubility of sulfamethizole through its complexation with beta- and hydroxypropyl-beta-cyclodextrin. Characterization of the interaction in solution and in solid state. Eur J Pharm Sci 2001; 13:325-31. [PMID: 11384856 DOI: 10.1016/s0928-0987(01)00131-2] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The aim of this study was to increase the solubility of sulfamethizole in water by complexing it with beta-cyclodextrin (BCD) and hydroxypropyl-beta-cyclodextrin (HPBCD). The interaction of sulfamethizole with the cyclodextrins was evaluated by the solubility, 1H NMR spectrometry and molecular modelling. The stability constants calculated from the phase solubility method increase in order HPBCD<BCD. From the NMR studies could be concluded that the sulfamethizole:cyclodextrin mole ratio was 1:1 (mol/mol) in the BCD complex and 2:3 (mol/mol) in the HPBCD complex. In both cases the sulfamethizole moiety included in the cyclodextrin was the thiadiazole group. MM2 calculations, either in vacuum or in the presence of a solvent, support this structure. Solid inclusion complexes of sulfamethizole with BCD and HPBCD were obtained by freeze drying 1:1 (mol/mol) solutions in aqueous ammonium hydroxide. Host-guest interactions were studied in the solid state by powder X-ray diffractometry and differential scanning calorimetry. The dissolution rates of sulfamethizole increased by the complexation with BCD or HPBCD.
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Affiliation(s)
- B Pose-Vilarnovo
- Departamento de Farmacia e Tecnoloxía Farmacéutica, Fac. de Farmacia, Univ. de Santiago de Compostela, Campus Sur, E-15782 Santiago de Compostela, Spain
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