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Inclusion Complexes (inclusion + complex)
Kinds of Inclusion Complexes Selected AbstractsCatalytic Polymerizations of Hydrophobic, Substituted, Acetylene Monomers in an Aqueous Medium by Using a Monomer/Hydroxypropyl- , -cyclodextrin Inclusion ComplexMACROMOLECULAR RAPID COMMUNICATIONS, Issue 2 2009Lei Ding Abstract Ten hydrophobic, substituted, acetylene monomers were examined as to their abilities to form an inclusion complex with hydroxypropyl- , -cyclodextrin (HPCD). Only the monomers with suitable substitutents were found to form the monomer/HPCD complex, which was identified by NMR, FTIR, and UV-vis spectroscopy. Polymerizations of the monomers were successfully carried out in aqueous solution by using the prepared monomer/HPCD inclusion complex and by using a water-soluble Rh-based catalyst, [Rh(cod)2BF4] or [Rh(nbd)(H2O)OTs]. Such polymerizations provided high-yield (>90%) polymers with a cis content of approximately 100%. The as-prepared polymers could take an ordered helical conformation, just like their counterparts obtained in organic solvents. [source] New [4 + 4] Photodimerization of 5-Chloro-2-pyridone to the meso-cis-syn Dimer as an Inclusion Complex with 1,2,4,5-Benzenetetracarboxylic Acid.CHEMINFORM, Issue 22 2005Shinya Hirano Abstract For Abstract see ChemInform Abstract in Full Text. [source] Asymmetric Reduction of Acetophenone and Propiophenone by NaAl(IPTOLate)H2 Combined with Enantiomeric Enrichment of the Reaction Product as an Inclusion Complex with IPTOL.CHEMINFORM, Issue 10 2004M. G. Vinogradov Abstract For Abstract see ChemInform Abstract in Full Text. [source] Crystal Structure of , -Cyclodextrin-Felbinac Inclusion ComplexCHINESE JOURNAL OF CHEMISTRY, Issue 10 2009Enju Wang Abstract The crystal structure of the inclusion complex of , -cyclodextrin (, -CD) synthesized with felbinac (4-biphenylacetic acid) was determined by single crystal X-ray diffraction at 150 K. The complex contains two , -CDs, two felbinac molecules, twenty-two water molecules in the asymmetric unit, and could be formulated as (C42H70O35)2·(C14H12O2)2·22(H2O). In the crystal lattice, the two , -CD moieties form a head-to-head dimer jointed through hydrogen bonds, and the felbinacs that interact by face-to-face ,-, stacking are included in the , -CD dimer cavity with their carboxyl groups protruding out from cavity opening. In crystals the dimer units of , -CD are stacked in an intermediate type (IM) that consists of closely packed , -CD dimer layers. [source] Synthesis and Structure of Inclusion Complex of Cyclomaltoheptaose (,-Cyclodextrin) with m - AminophenolCHINESE JOURNAL OF CHEMISTRY, Issue 4 2002Jin-Ling Wang Abstract The supramolecular compound, ,-CD/m -aminophenol [(C42H70O35)·(C6H7ON)·(H2O)7.5·CH3OH], was synthesized and characterized by X-ray diffraction analysis. It crystallizes in monoclinic system, P21 space group, with a = 1.5122(4) nm, b=1.0335(4) nm, c=2.0915(3) nm, ,=109.58(2)°, V = 3.0798(3) nm3 and final R = 0.0598. The system belongs to "shallow inclusion" which is rarely found. In this supramolecule, the guest is located over the narrow rim of the host There are so many hydrogen bonds that they build a dense hydrogen bond net. The hydrogen-bond interactions are the main force to form the whole system and keep the stability. [source] Inclusion Complexes for Use in Room-Temperature Gas-Sensor DesignEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 33 2007Liwei Mi Abstract The inclusion complex [{Co(bpy)(H2O)4}·(fcds)]n (1), which has been constructed using the guest molecule ferrocene-1,1,-disulfonate (fcds), the bridging ligand 4,4,-bipyridine (bpy) and d7 Co2+, contains an infinite zigzag chain formed by the central CoII ion and the bridging bpy ligand. Guest fcds molecules lie between two adjacent zigzag chains. The highly conjugated structure of complex 1 means that it can be used as a metal-organic semiconductor, and it also shows a high response to liquefied petroleum gas (LPG) and ethanol/petroleum ether (EP) at room temperature. The inclusion complexes [{Co(bpp)2(H2O)2}·(fcds)·4H2O]n [2; bpp = 1,3-bis(4-pyridyl)propane] and [{Zn(bpy)(H2O)4}·(fcds)]n (3), on the other hand, cannot be employed as room-temperature gas sensors because they are insulators. The electrical resistivity of inclusion complex [{Ni(bpy)(H2O)4}·(fcds)]n (4) is 621 M,, whereas that of [{Co(bpy)(H2O)4}SO4·(4-abaH)2·3H2O]n (5) (4-abaH = 4-aminobenzoic acid) is only 137 M,. This means that the semi-conducting properties of such inclusion complexes depend on both the conjugated structure and the central metal ions. Furthermore, conjugated inclusion complexes with an odd number of electrons could be useful for the design of highly selective room-temperature gas sensors.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Comparison of Cyclodextrin-Dipeptide Inclusion Complexes in the Absence and Presence of Urea by Means of Capillary Electrophoresis, Nuclear Magnetic Resonance and Molecular ModelingEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 18 2007Benjamin Waibel Abstract The use of capillary electrophoresis (CE) modified with cyclodextrin (CD) for the separation of stereoisomers of peptides is well established. To increase the solubility of ,-CD, urea is often added to the buffer which may influence the complexation of a CD with a guest molecule. The aim of the present study was to investigate the influence of urea on the complexation between dipeptides and ,-CD using Ala-Phe and Ala-Tyr as model compounds. For this purpose three different analytical methods were employed: capillary electrophoresis (CE), 1H-NMR spectroscopy and molecular dynamics simulations (MD). Electropherograms of the peptide enantiomers were different in the presence and absence of urea. For example, at pH,2.5 in the absence of urea the enantiomers of Ala-Tyr are not separated in contrast to the use of buffers containing urea. Applying "complexation-induced chemical shift (CICS)" in NMR spectroscopy and rotating frame Overhauser enhancement spectroscopy (ROESY) revealed differences in the complexation of the peptide enantiomers by ,-CD in the absence and presence of urea suggesting the stabilization of the complex through the phenolic hydroxyl group of tyrosine. MD simulations for different complexes were carried out with consideration of both water and urea molecules in solution. Simulations were performed for 1 ns. In conclusion, NMR spectroscopy and MD methods help to understand the structure of peptide-CD complexes and the separation and migration behavior in CE. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Preparation of Highly Transparent and Thermally Stable Films of , -Cyclodextrin/Polymer Inclusion ComplexesMACROMOLECULAR RAPID COMMUNICATIONS, Issue 21 2007Takafumi Mori Abstract Films of an , -cyclodextrin/poly(, -caprolactone) inclusion complex have been successfully prepared and show high transparency and heat resistance in comparison to the pure polymer film. The physical properties, such as transparency, mechanical properties, and thermal stability, of the , -CD-PCL-IC films are found to depend on the , -cyclodextrin-to-polymer stoichiometry. [source] Observation of Photochromic ,-Cyclodextrin Host,Guest Inclusion Complexes.CHEMINFORM, Issue 43 2002Suman Iyengar Abstract For Abstract see ChemInform Abstract in Full Text. [source] Site-Selective Formation of Optically Active Inclusion Complexes of Alkoxo-Subphthalocyanines with ,-Cyclodextrin at the Toluene/Water InterfaceCHEMISTRY - A EUROPEAN JOURNAL, Issue 16 2006Kenta Adachi Abstract Several subphthalocyanine derivatives that contain an alkoxo substituent as an axial ligand (RO-Subpc, R = 9-anthracenemethyl, benzyl, phenyl, 3,5-dimethylbenzyl, 3,5-dimethylphenyl, 4-methylbenzyl, and 4-methylphenyl) were synthesized. The formation of inclusion complexes of RO-Subpc with ,-CD in DMSO and at the toluene/water interface was investigated by UV/Vis absorption spectroscopy, induced circular dichroism (ICD), and nuclear magnetic resonance (NMR) measurements. Interfacial tension measurements suggested that ,-CD adsorbed as a monolayer at the toluene/water interface and probably orientated towards the toluene phase with its primary face. The 1:1 composition of ,-CD,RO-Subpc inclusion complexes was confirmed in DMSO and at the toluene/water interface for BzO-Subpc, PhO-Subpc, MeBzO-Subpc, and MePhO-Subpc. A 2:1 inclusion complex of AnO-Subpc formed in DMSO. The observed ICD spectra of ,-CD,RO-Subpc inclusion complexes are discussed with respect to molecular modeling and the simulation based on Tinoco,Kirkwood theory. Interestingly, the ICD spectra of ,-CD,BzO-Subpc and ,-CD,MeBzO-Subpc inclusion complexes exhibited a negative sign in DMSO and a positive sign at the toluene/water interface. This reversal of the ICD sign strongly suggests a difference in the structure of the inclusion complexes: ,-CD at the interface formed the inclusion complex with its primary face, whereas the secondary face of ,-CD bound favorably to RO-Subpc in DMSO. [source] Preparation and Characterization of Inclusion Complexes of ,-Cyclodextrin with Ionic LiquidCHEMISTRY - A EUROPEAN JOURNAL, Issue 20 2005Yan-An Gao Abstract The solubilities of ,-cyclodextrin (,-CD), ionic liquid (IL) 1-butyl-3-methylimidazolium hexafluorophosphate (bmimPF6), and their mixture in water were determined, and the conductivity of these aqueous solutions was measured. It was demonstrated that ,-CD and bmimPF6 could enhance the solubility of each other, and the solubility curves of each were linear with gradients of about 1. The conductivity decreased remarkably with increasing , - CD concentration, and a discernible break in the conductivity curve could be observed when ,-CD and bmimPF6 were equimolar in the solution. The solubility and conductivity results indicated that inclusion complexes (ICs) of 1:1 stoichiometry were formed. The inclusion compounds were further characterized by using powder X-ray diffraction (XRD) analysis, 13C CP/MAS (cross-polarization magic-angle spinning) NMR and 1H NMR spectroscopy, and thermogravimetric analysis (TGA). The results showed that the ICs were a fine crystalline powder. The host,guest system exhibited a channel-type structure and each glucose unit of ,-CD was in a similar environment. The decomposition temperature of the ICs was lower than that of bmimPF6 and ,-CD individually. [source] Transformation of a zinc inclusion complex to wurtzite ZnS microflowers under solvothermal conditionsCRYSTAL RESEARCH AND TECHNOLOGY, Issue 9 2010Liwei Mi Abstract Wurtzite zinc sulfide (ZnS) microflowers were synthesized successfully by a convenient solvothermal route in ethylene glycol (EG) and ethylenediamine (EN) using thiourea and zinc inclusion complex as starting materials. The inclusion complex {[Zn(bipy)2(H2O)2](4-Cl-3-NH2 -C6H3SO3)2(bipy) (H2O)2}n was achieved by the reaction of zinc oxide (ZnO) and 4-Cl-3-NH2 -C6H3SO3 with the bridging ligand bipy under moderate conditions, in which bipy is 4,4,-bipyridine and 4-Cl-3-NH2C6H3SO3NH is 4-Chloro-3-aminobenzene sulfonic acid. The phase purity of bulk products was confirmed by powder X-ray diffraction and element analysis. The factors that might affect the purity of the ZnS product during the synthesis were discussed in detail. It was found that the products were significantly affected by the mixed solvents and the starting materials. X-ray single crystal diffraction, scanning electron microscopy (SEM), energy-dispersive X-ray spectrometry (EDS), and X-ray diffraction (XRD) were used to characterize the products. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Inclusion Complexes for Use in Room-Temperature Gas-Sensor DesignEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 33 2007Liwei Mi Abstract The inclusion complex [{Co(bpy)(H2O)4}·(fcds)]n (1), which has been constructed using the guest molecule ferrocene-1,1,-disulfonate (fcds), the bridging ligand 4,4,-bipyridine (bpy) and d7 Co2+, contains an infinite zigzag chain formed by the central CoII ion and the bridging bpy ligand. Guest fcds molecules lie between two adjacent zigzag chains. The highly conjugated structure of complex 1 means that it can be used as a metal-organic semiconductor, and it also shows a high response to liquefied petroleum gas (LPG) and ethanol/petroleum ether (EP) at room temperature. The inclusion complexes [{Co(bpp)2(H2O)2}·(fcds)·4H2O]n [2; bpp = 1,3-bis(4-pyridyl)propane] and [{Zn(bpy)(H2O)4}·(fcds)]n (3), on the other hand, cannot be employed as room-temperature gas sensors because they are insulators. The electrical resistivity of inclusion complex [{Ni(bpy)(H2O)4}·(fcds)]n (4) is 621 M,, whereas that of [{Co(bpy)(H2O)4}SO4·(4-abaH)2·3H2O]n (5) (4-abaH = 4-aminobenzoic acid) is only 137 M,. This means that the semi-conducting properties of such inclusion complexes depend on both the conjugated structure and the central metal ions. Furthermore, conjugated inclusion complexes with an odd number of electrons could be useful for the design of highly selective room-temperature gas sensors.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Evaluation of gastric toxicity of indomethacin acid, salt form and complexed forms with hydroxypropyl-,-cyclodextrin on Wistar rats: histopathologic analysisFUNDAMENTAL & CLINICAL PHARMACOLOGY, Issue 6 2009A.C. Ribeiro-Rama Abstract Indomethacin (IM) is a non-steroidal anti-inflammatory drug which inhibits prostaglandin biosynthesis. It is practically insoluble in water and has the capacity to induce gastric injury. Hydroxypropyl-,-cyclodextrin (HP-,-CD) is an alkylated derivative of ,-CD with the capacity to form inclusion complexes with suitable molecules. IM is considered to form partial inclusion complexes with HP-,-CD by enclosure of the p -chlorobenzoic part of the molecule in the cyclodextrin channel, reducing the adverse effects. The aim of this paper is to evaluate the gastric damage induced by the IM inclusion complex prepared by freeze-drying and spray-drying. A total of 135 Wistar rats weighing 224.4 ± 62.5 g were put into 10 groups. They were allowed free access to water but were maintained fasted for 18 h before the first administration until the end of the experiment. IM acid-form, IM trihydrated-sodium-salt and IM-HP-,-CD spray and freeze-dried, at normal and toxic doses, were administered through gastric cannula once/day for 3 days. Seventy-two hours after the first administration, the animals were sacrificed and the stomachs collected and prepared for morphological study by using the haematoxylin-eosin technique. Lesion indexes (rated 0/4) were developed and the type of injury was scored according to the severity of damage and the incidence of microscopic evidence of harm. Microscopic assessment demonstrated levels of injury with index one on 10,25%. The type of complexation method had different incidence but the same degree. The results show that IM inclusion complexation protects against gastric injury, reducing the incidence and the maximum degree of severity from 4 to 1, with a better performance of the spray-dried complex. [source] , -Cyclodextrin as Inhibitor of the Precipitation Reaction between Berberine and Glycyrrhizin in Decoctions of Natural Medicines: Interaction Studies of Cyclodextrins with Glycyrrhizin and Glycyrrhetic Acid by 1H-NMR Spectroscopy and Molecular-Dynamics CalculationHELVETICA CHIMICA ACTA, Issue 9 2008Miyoko Kamigauchi Abstract To prevent the precipitation reaction between glycyrrhizin (1) and berberine (3) in the decoctions of Glycyrrhiza/Coptis rhizome or Glycyrrhiza/Phellodendron bark, the presence of cyclodextrin (CD) in the mixture was proven to be effective. The preventing effect decreased in the order , -CD>, -CD, and no effect was observed for , -CD. On the other hand, the extraction degree of 1 from the natural medicine Glycyrrhia was considerably increased in the presence of , -CD, , -CD being much more effective than , - or , -CD. Thus, the blocking effect of CD on the precipitate formation between 1 and 3 is suggested to be primarily dependent on the stability of the inclusion complex of the CD with 1. To establish the structure of such a preferred inclusion complex, the interactions of 1 with , - and , -CDs were investigated by 1H-NMR spectroscopy and molecular-dynamics (MD) calculations. The 1H-NMR measurements showed that the increase in solubility of 1 in H2O is dependent on the degree of its inclusion into the CD, which depends on the molecular size of the CD. The MD calculations suggested that the H-bond interactions are sufficiently strong to form a stable [1/, -CD] complex, in which the lipophilic rings C, D, and E of 1 are fully inserted into the molecular cavity of , -CD, thus forming a kind of structure covered by a hydrophilic molecular capsule, while such an interaction mode is impossible for , - or , -CD. [source] Using hydroxypropyl-,-cyclodextrin for the preparation of hydrophobic poly(ketoethyl methacrylate) in aqueous mediumJOURNAL OF APPLIED POLYMER SCIENCE, Issue 5 2010Lei Ding Abstract This work was committed to the polymerization of hydrophobic ketoethyl methacrylate monomer in aqueous medium in the presence of cyclodextrin, instead of polymerizing the monomer in toxic and volatile organic solvents. For this purpose, a new ketoethyl methacrylate monomer, p -methylphenacylmethacrylate (MPMA), was synthesized from the reaction of p -methylphenacylbromide with sodium methacrylate in the presence of triethylbenzylammonium chloride. The monomer was identified with FTIR, 1H and 13C-NMR spectroscopies. Hydroxypropyl-,-cyclodextrin (HPCD) was used to form a water-soluble host/guest inclusion complex (MPMA/HPCD) with the hydrophobic monomer. The complex was identified with FTIR and NMR techniques and polymerized in aqueous medium using potassium persulfate as initiator. During polymerization the resulting hydrophobic methacrylate polymer precipitated out with a majority of HPCD left in solution and a minority of HPCD bonded on the resulting polymer. The thus-prepared polymer exhibited little difference from the counterparts obtained in organic solvent in number average molecular weight (Mn), polydispersity (Mw/Mn) and yield. The investigation provides a novel strategy for preparing hydrophobic ketoethyl methacrylate polymer in aqueous medium by using a monomer/HPCD inclusion complex. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 [source] Alkaline hydrolysis of cinnamaldehyde to benzaldehyde in the presence of ,-cyclodextrinAICHE JOURNAL, Issue 2 2010Hongyan Chen Abstract A facile, novel, and cost-effective alkaline hydrolysis process of cinnamaldehyde to benzaldehyde under rather mild conditions has been investigated systematically in the presence of ,-cyclodextrin (,-CD), with water as the only solvent. ,-CD could form inclusion complex with cinnamaldehyde in water, with molar ratio of 1:1, so as to promote the reaction selectivity. The complex has been investigated experimentally and with computational methods. 1H-NMR, ROESY, UV,Vis, and FTIR have been utilized to analyze the inclusion complex. It shows that the equilibrium constant for inclusion (Ka) is 363 M,1, and the standard Gibbs function for the reaction, ,,G (298 K), is ,14.6 kJ mol,1. In addition, the structures of the proposed inclusion compounds were optimized with hybrid ONIOM theory. Benzaldehyde could be obtained at an yield of 42% under optimum conditions [50°C, 18 h, 2% NaOH (w/v), cinnamaldehyde:,-CD (molar ratio) = 1:1]. To explain the experimental data, NMR, FTIR, and elemental analysis results were used to determine the main reaction by-product 1-naphthalenemethanol. A feasible reaction mechanism including the retro-Aldol condensation of cinnamaldehyde and the Aldol condensation of acetaldehyde and cinnamaldehyde in basic aqueous ,-CD solution has been proposed. The calculated activation energy for the reaction was 45.27 kJ mol,1 by initial concentrations method. © 2009 American Institute of Chemical Engineers AIChE J, 2010 [source] Piroxicam/2-hydroxypropyl-,-cyclodextrin inclusion complex prepared by a new fluid-bed coating techniqueJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 2 2009Xingwang Zhang Abstract This work was aimed at investigating the feasibility of fluid-bed coating as a new method to prepare cyclodextrin inclusion complex. The inclusion complex of the model drug piroxicam (PIX) and 2-hydroxypropyl-,-cyclodextrin (HPCD) in aqueous ethanol solution was sprayed and deposited onto the surface of the pellet substrate upon removal of the solvent. The coating process was fluent with high coating efficiency. Scanning electron microscopy revealed a coarse pellet surface, and a loosely packed coating structure. Significantly enhanced dissolution, over 90% at 5 min, was observed at stoichiometric PIX/HPCD molar ratio (1/1) and at a ratio with excessive HPCD (1/2). Differential scanning calorimetry and powder X-ray diffractometry confirmed absence of crystallinity of PIX at PIX/HPCD molar ratio of 1/1 and 1/2. Fourier transform-infrared spectrometry and Raman spectrometry revealed interaction between PIX and HPCD adding evidence on inclusion of PIX moieties into HPCD cavities. Solid-state 13C NMR spectrometry indicated possible inclusion of PIX through the pyridine ring. It is concluded that fluid-bed coating has potential to be used as a new technique to prepare cyclodextrin inclusion complex. © 2008 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 98:665,675, 2009 [source] Characterisation of an inclusion complex between cladribine and 2-hydroxypropyl-,-cyclodextrin,JOURNAL OF PHARMACEUTICAL SCIENCES, Issue 9 2008Valeria Van Axel Castelli Abstract Parenterally administered cladribine (2-chloro-2,-deoxyadenosine) has demonstrated promising efficacy and safety in clinical trials in patients with multiple sclerosis (MS). An oral formulation of this small molecule would be an attractive option for patients. Here, we describe the chemical characterisation of the inclusion complex between cladribine and the drug carrier molecule 2-hydroxypropyl-,-cyclodextrin (2-HP-,-CD). Several techniques were used to analyse the complex both in solution and in the solid state. These analyses provided evidence that the inclusion complex cannot be simply reduced to the sum of the two species, as it shows behaviour different from that of the physical mixture of the two components. Furthermore, solution nuclear magnetic resonance spectroscopy demonstrated the existence of an inclusion complex between cladribine and 2-HP-,-CD. Importantly, analysis of a tablet formulation demonstrated that the chemical characteristics of the inclusion complex are not affected by the manufacturing process, and that the complex is stable during storage. This tablet formulation is currently under investigation for the treatment of patients with MS. © 2008 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 97:3897,3906, 2008 [source] Inhibitory effect of sulfobutyl ether ,-cyclodextrin on DY-9760e-induced cellular damage: In vitro and in vivo studiesJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 12 2003Yukihiko Nagase Abstract The effects of water-soluble ,-cyclodextrin derivatives (,-CyDs), such as 2-hydroxypropyl-,-cyclodextrin (HP-,-CyD) and sulfobutyl ether ,-cyclodextrin (SBE7-,-CyD) on cytotoxicity of DY-9760e (3-[2-[4-(3-chloro-2-methylphenyl)-1-piperazinyl]ethyl]-5,6-dimethoxy-1-(4-imidazolylmethyl)-1H -indazole dihydrochloride 3.5 hydrate) toward human umbilical vein endothelial cells (HUVECs) in vitro and vascular damage of the auricular vein of rabbits by DY-9760e in vivo were investigated. The spectroscopic study revealed that of the four ,-CyDs SBE7-,-CyD forms the most stable inclusion complex in phosphate-buffered saline, probably because of a synergetic effect of hydrophobic and electrostatic interactions. ,-CyDs inhibited DY-9760e-induced cell death toward HUVECs in an order of G2 -,-CyD,<,,-CyD,<,HP-,-CyD,<,SBE7-,-CyD, which was consistent with the order of the magnitude of stability constants. When the DY-9760e solution was infused into the auricular vein of rabbits for 24 h, SBE7-,-CyD suppressed a DY-9760e-induced irritation such as thrombus, desquamation of the endothelium vasculitis, and perivasculitis. The present data indicated that SBE7-,-CyD formed an inclusion complex with DY-9760e in a buffer solution and possessed the protective effect on DY-9760e-induced cytotoxicity toward HUVECs and vascular damage in rabbits. These results suggested potential use of SBE7-,-CyD as a parenteral carrier for DY-9760e. © 2003 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 92:2466,2474, 2003 [source] Enhanced solubility and dissolution rate of lamotrigine by inclusion complexation and solid dispersion techniqueJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 9 2008Vikram R. Shinde ABSTRACT The solid-state properties and dissolution behaviour of lamotrigine in its inclusion complex with ,-cyclodextrin (,CD) and solid dispersions with polyvinylpyrrolidone K30 (PVP K30) and polyethyl-eneglycol 6000 were investigated. The phase solubility profile of lamotrigine with ,CD was classified as AL -type, indicating formation of a 1:1 stoichiometry inclusion complex, with a stability constant of 369.96 ± 2.26 M,1. Solvent evaporation and kneading methods were used to prepare solid dispersions and inclusion complexes, respectively. The interaction of lamotrigine with these hydrophilic carriers was evaluated by powder X-ray diffractometry, Fourier transform infrared spectroscopy and differential scanning calorimetry. These studies revealed that the drug was no longer present in crystalline state but was converted to an amorphous form. Among the binary systems tested, PVP K30 (1:5) showed greatest enhancement of the solubility and dissolution of lamotrigine. [source] The role of specific interactions in crystalline complex formation.JOURNAL OF PHYSICAL ORGANIC CHEMISTRY, Issue 5 200210-bis(4-bromophenyl)-, 10-dihydroanthracene with dimethyl sulfoxide, 10-dihydroxy-, Structural, thermochemical analysis of inclusion compounds of cis -, trans - Abstract Referring to a crucial problem in crystal engineering and co-crystallization of host,guest complexes, whether the non-covalent supramolecular interactions existing in a pre-crystalline solution state may determine the subsequent crystal structure, the particular inclusion properties of host compounds 1, cis - and 2, trans -9,10-bis(4-bromophenyl)-9,10-dihydroxy-9,10-dihydroanthracene, with dimethyl sulfoxide (DMSO) were studied by using x-ray structure analysis and calorimetric methods. Both hosts form crystalline inclusion complexes with DMSO showing 2:3 (1·DMSO) and 1:4 (2·DMSO) host:guest composition. The crystal structure of 1·DMSO (2:3) is dominated by a strong bifurcated acceptor-type H bond interaction involving 1 and one of the DMSO molecules. Titration calorimetric investigations in solution also confirm the formation of a stable 1·DMSO (1:1) complex unit, suggesting that for crystal nuclei of 1·DMSO (2:3) the pre-formed 1:1 host,guest complex is the relevant building block while the additional molecules of DMSO fill lattice voids. In contrast, compound 2 with a trans configuration of the two hydroxy groups gives much weaker complexation with DMSO in solution, which is in agreement with single H-bond interaction, also realized in the crystal structure of the respective inclusion complex. Thermal decomposition (TG,DSC) measurements of the crystalline complexes supply supporting data for these findings. Copyright © 2002 John Wiley & Sons, Ltd. [source] Photoreactive nanomatrix structure formed by graft-copolymerization of 1,9-nonandiol dimethacrylate onto natural rubberJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 11 2010Yoshimasa Yamamoto Abstract Formation of photoreactive nanomatrix structure was investigated by graft-copolymerization of an inclusion complex of 1,9-nonandiol dimethacrylate (NDMA) with ,-cyclodextrin (,-CD) onto natural rubber particle using potassium persulfate (KPS), tert -butyl hydroperoxide/tetraethylenepentamine (TBHPO/TEPA), cumene hydroperoxide/tetraethylenepentamine (CHPO/TEPA), and benzoyl peroxide (BPO) as an initiator. The graft copolymer was characterized by 1H NMR and FTIR after coagulation. The conversion of NDMA and the amount of residual methacryloyl group were found to be 58.5 w/w % and 1.81 w/w %, respectively, under the suitable condition of the graft-copolymerization. The morphology of the film specimen, prepared from the graft copolymer, was observed by transmission electron microscopy (TEM) after staining the film with OsO4. Natural rubber particle of about 1.0 ,m in diameter was dispersed in poly(NDMA) matrix of about 10 nm in thickness. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 2418,2424, 2010 [source] Polyrotaxanes based on polyethers and ,-cyclodextrinJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 17 2009Saloua Chelli Abstract A polyrotaxane in which ,-cyclodextrins (,-CDs) are threaded onto a polyether chain was prepared by polycondensation of a ,-CD/bisphenol A (BPA) inclusion complex with aromatic dihalides. Two dihalides, with and without a side chain, were used. This polycondensation results in a polyrotaxane (or pseudopolyrotaxane for polymers without stoppers) with a 1:1 threading ratio when the side chain is present and 2:3 when there is none. The long side chain prevents dethreading of the macrocycles. The best yield and a good threading ratio were obtained when the polycondensation was performed by liquid,solid phase transfer catalysis without solvent (L/S PTC) using 2,5-bi(iodomethyl)-4-methoxy-(1-octyloxy)benzene as dihalide. The 1H NMR and FTIR spectra show that the products consist of ,-CD and polyether. The 2D NOESY NMR spectrum shows that the polyether chains are included in the ,-CD cavity. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4391,4399, 2009 [source] Using glycidyl methacrylate as cross-linking agent to prepare thermosensitive hydrogels by a novel one-step methodJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 6 2008Jianping Deng Abstract A novel one-step approach is reported to prepare thermosensitive hydrogels simply by using hydroxypropyl-,-cyclodextrin (HP-,-CD)/glycidyl methacrylate (GMA)/N -isopropylacrylamide (NIPAM) system. From GMA and HP-,-CD, HP-,-CD/GMA inclusion complex was prepared and identified with NMR, FTIR, and UV-vis spectroscopies. GMA in the form of HP-,-CD/GMA complex was copolymerized with NIPAM in water with K2S2O8 as initiator, yielding hydrogels designated as poly(NIPAM-CD-GMA). The inclusion of CD in the hydrogels was confirmed by FTIR spectroscopy. The contents of CD and GMA placed considerable influence on the swelling ratio and temperature-sensitivity of the produced hydrogels. The hydrogels bearing CD moieties showed higher swelling ratio and temperature-sensitivity when compared with that without CD. The porous structure of the hydrogels containing CD was observed in the SEM images. Relevant mechanism of the ring-opening reaction of epoxide groups in GMA, the subsequent crosslinking reactions and the formation of hydrogels containing CD moieties were proposed. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 2193,2201, 2008 [source] Application of functional group modified substrate in room-temperature phosphorescence, I,, -cyclodextrin modified paper substrate for enrichment and determination of fluorene and acenaphtheneLUMINESCENCE: THE JOURNAL OF BIOLOGICAL AND CHEMICAL LUMINESCENCE, Issue 4-5 2005Ruohua Zhu Abstract A novel method for the determination of fluorene and acenaphthene on solid phase extraction,room-temperature phosphorescence (SPE,RTP) was studied. , -cyclodextrin (, -CD) was chemically bonded onto chromatography paper by reaction with epichorohydrin in an ultrasonic bath. The RTP signal of fluorene and acenaphthene included on the , -CD-modified paper was increased more than 10 times compared with non-modified filter paper, indicating the formation of the inclusion complex. The conditions for the of RTP of compounds were studied in detail. The linear ranges of fluorene and acenaphthene concentrations to the RTP intensity were over two orders of magnitude (8.0 × 10,7,4.0 × 10,5 mol/L for fluorene) with a correlation coefficient of 0.999. The concentration limits of detection for fluorene and acenaphthene were 1.11 × 10,8 mol/L and 3.8 × 10,7 mo/L, respectively. When the sampling volume was 10 µL, the absolute LODs for fluorene and acenaphthene were 18.4 pg/spot and 0.58 ng/spot, respectively. The modified filter paper was used for solid phase extraction (SPE) and the retention behaviour of fluorene and acenaphthene was examined. The enrichment efficiency of the analytes was higher than 100-fold. The SPE,RTP coupling technique was applied directly to the determination of fluorene and acenaphthnene in environmental water samples. Copyright © 2005 John Wiley & Sons, Ltd. [source] Cyclodextrins in Polymer Synthesis: Enzymatic Polymerization of a 2,6-Dimethyl- , -Cyclodextrin/2,4-Dihydroxyphenyl-4,-Hydroxybenzylketone Host-Guest Complex Catalyzed by Horseradish Peroxidase (HRP)MACROMOLECULAR BIOSCIENCE, Issue 8 2003Lorenzo Mejias Abstract This paper reports the enzymatic polymerization of the inclusion complex 2,4-dihydroxyphenyl-4,-hydroxybenzylketone/2,6-dimethyl- , -cyclodextrin by horseradish peroxidase (HRP) in aqueous media. The structure of the complex was determined by means of NOESY-NMR and crystallographic analysis (indicating an orthorhombic structure). The enzymatic polymerization of the uncomplexed 2,4-dihydroxyphenyl-4,-hydroxybenzylketone yields oligomers with molecular weights up to in organic-aqueous media, but because of its poor solubility in aqueous systems, no polymerization is observed if water is used as solvent. An increase of the availability of the ketone in solution is achieved by complexing it with random-methylated , -cyclodextrin in water. We found that the use of methylated , -cyclodextrin in equimolar concentration to the monomer increases the polymerization yield and the average molecular weight. The polymers formed were analyzed by GPC and ATR-FTIR techniques. Representation from X-ray diffraction analysis of the 2,6-dimethyl- , -cyclodextrin/2,4-dihydroxyphenyl-4,-hydroxybenzylketone host-guest complex (3). [source] Catalytic Polymerizations of Hydrophobic, Substituted, Acetylene Monomers in an Aqueous Medium by Using a Monomer/Hydroxypropyl- , -cyclodextrin Inclusion ComplexMACROMOLECULAR RAPID COMMUNICATIONS, Issue 2 2009Lei Ding Abstract Ten hydrophobic, substituted, acetylene monomers were examined as to their abilities to form an inclusion complex with hydroxypropyl- , -cyclodextrin (HPCD). Only the monomers with suitable substitutents were found to form the monomer/HPCD complex, which was identified by NMR, FTIR, and UV-vis spectroscopy. Polymerizations of the monomers were successfully carried out in aqueous solution by using the prepared monomer/HPCD inclusion complex and by using a water-soluble Rh-based catalyst, [Rh(cod)2BF4] or [Rh(nbd)(H2O)OTs]. Such polymerizations provided high-yield (>90%) polymers with a cis content of approximately 100%. The as-prepared polymers could take an ordered helical conformation, just like their counterparts obtained in organic solvents. [source] Preparation of Highly Transparent and Thermally Stable Films of , -Cyclodextrin/Polymer Inclusion ComplexesMACROMOLECULAR RAPID COMMUNICATIONS, Issue 21 2007Takafumi Mori Abstract Films of an , -cyclodextrin/poly(, -caprolactone) inclusion complex have been successfully prepared and show high transparency and heat resistance in comparison to the pure polymer film. The physical properties, such as transparency, mechanical properties, and thermal stability, of the , -CD-PCL-IC films are found to depend on the , -cyclodextrin-to-polymer stoichiometry. [source] NMR spectroscopic characterization of inclusion complexes comprising cyclodextrins and gallated catechins in aqueous solution: cavity size dependencyMAGNETIC RESONANCE IN CHEMISTRY, Issue 4 2009Takashi Ishizu Abstract The structure of inclusion complexes of ,-cyclodextrin (,-CD), (,)-gallocatechin gallate (GCg), and (,)-epigallocatechin gallate (EGCg) in D2O was investigated using several NMR techniques. GCg formed a 1:1 inclusion complex with ,-CD in which the A and C rings of GCg were inserted deep at the head of the A ring into the ,-CD cavity from the wide secondary hydroxyl group side. In the 1:1 inclusion complex with GCg and ,-CD, the GCg moiety maintained a conformation in which the B and B, rings of GCg took both pseudoequatorial positions with respect to the C ring. The structure of the inclusion complex of GCg and ,-CD obtained from NMR experiments supported well that determined from PM6 semiempirical SCF MO calculations. However, 1H NMR experiments suggested that EGCg did not form any inclusion complex with ,-CD in D2O. The marked difference between GCg and EGCg in inclusion behavior toward ,-CD may be explained in terms of the stabilization energy calculated with the PM6 method. Copyright © 2008 John Wiley & Sons, Ltd. [source] | ||||||||||||||||||||||||||||||||||||||||