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Search for "inclusion complex" in Full Text gives 102 result(s) in Beilstein Journal of Organic Chemistry.
Thermal and oxidative stability of Atlantic salmon oil (Salmo salar L.) and complexation with β-cyclodextrin
Beilstein J. Org. Chem. 2016, 12, 179–191, doi:10.3762/bjoc.12.20
- support the conclusion of formation of the β-CD/FA glyceride inclusion complex by means of water behavior. Hydration water is easier released from the β-CD/ASO complexes obtained at a 3:1 molar ratio. Both DSC and KFT analyses demonstrate this finding with a lower peak temperature and lower “strongly
A journey in bioinspired supramolecular chemistry: from molecular tweezers to small molecules that target myotonic dystrophy
Beilstein J. Org. Chem. 2016, 12, 125–138, doi:10.3762/bjoc.12.14
- how two units of Kagan’s ether provide the necessary C-shaped geometry [29]. Then, Harmata himself synthesized tweezer 18, reporting its solution binding studies and a beautiful solid-state inclusion complex with trinitrobenzene [30]. This series of molecular tweezers was reviewed in 2004 [31]. A
Supramolecular structures based on regioisomers of cinnamyl-α-cyclodextrins – new media for capillary separation techniques
Beilstein J. Org. Chem. 2016, 12, 97–109, doi:10.3762/bjoc.12.11
- and even polymers [5]. Modification of the parent CD molecule with an apolar substituent, which can form an inclusion complex with the CD’s cavity results in a conjugate with an ability to self-associate into supramolecular assemblies in polar solvents. The formation of these structures is based
Determination of formation constants and structural characterization of cyclodextrin inclusion complexes with two phenolic isomers: carvacrol and thymol
Beilstein J. Org. Chem. 2016, 12, 29–42, doi:10.3762/bjoc.12.5
- with generally observed results for aromatic monoterpenes [17][18][28]. Kf values (Table 1) were calculated based on the absorbance variations using an algorithmic treatment. Only a Kf value of the HP-β-CD/2 inclusion complex, determined by fluorescence spectroscopy, was found in the literature (1400 M
- guest is crucial to allow the formation of a stable inclusion complex. This is mainly controlled by the chemical structure of the encapsulated guest. Kf values generally increase for guests with an isopropyl moiety. Indeed, p-cymene [36] showed higher Kf values than toluene [37]. However, the comparison
- lipophilic cavity. This supported the fact that hydrophobic forces play a leading role in inclusion complex formation. Although ΔE values clearly illustrate the stability of each inclusion complex, it has to be underlined that such theoretical energies cannot be directly compared to Kf values, as the
Physical properties and biological activities of hesperetin and naringenin in complex with methylated β-cyclodextrin
Beilstein J. Org. Chem. 2015, 11, 2763–2773, doi:10.3762/bjoc.11.297
- hesperetin with cyclodextrins (β-CD and DM-β-CD) were theoretically investigated by molecular dynamics simulation. The free energy values obtained suggested a more stable inclusion complex with DM-β-CD. The vdW force is the main guest–host interaction when hesperetin binds with CDs. The phase solubility
- 1). For naringenin/β-CD and naringenin/DM-β-CD, the ∆EvdW values were −25.69 and −29.71 kcal·mol−1 while ∆Eele values were −4.09 and −4.73 kcal·mol−1, respectively [40] (Supporting Information File 1). Thus, the vdW interaction played an important role in forming the inclusion complex. The obtained
- stability was mainly governed by the vdW interaction. DSC analysis To investigate the solid inclusion complex obtained by freeze-drying (Figure 3D and E) and kneading methods (Figure 3F and G), DSC measurements were performed. The thermogram revealed information about the thermal properties of the starting
Synthesis and photophysical characteristics of polyfluorene polyrotaxanes
Beilstein J. Org. Chem. 2015, 11, 2677–2688, doi:10.3762/bjoc.11.288
- conjugated polymers [16][17][18][19][20][26][27][28][29][30][31][32][33][34][35][36][37][38]. The first step in the preparation of conjugated polyrotaxanes is the threading of macrocyclic compounds (hosts) onto linear chains (guests), when a thermodynamically unstable inclusion complex (IC) is obtained. A
- molecules were synthesized according to previously reported procedure [47][48]. Synthesis of 1·TM-βCD: To prepare 1·TM-βCD inclusion complex, 0.572 g (0.4 mmol) of TM-βCD were dissolved in water (5.0 mL) and 0.067 g (0.2 mmol) of 2 were added. The mixture was stirred at room temperature under nitrogen
- atmosphere for 48 h to give a turbid dispersion. The water was removed by lyophilization and the complex, as a white powder was used for the preparation of 1·TM-βCD. The synthesis of the inclusion complex 1·TM-γCD was performed under similar experimental conditions as those used for the preparation of the 1
Inclusion complexes of 2-methoxyestradiol with dimethylated and permethylated β-cyclodextrins: models for cyclodextrin–steroid interaction
Beilstein J. Org. Chem. 2015, 11, 2616–2630, doi:10.3762/bjoc.11.281
- host–guest β-CD inclusion complex, prepared by two methods, yielded very rapid dissolution in water at 37 °C relative to untreated 2ME, attaining complete dissolution within 15 minutes (co-precipitated complex) and 45 minutes (complex from kneading). Keywords: complexation; cyclodextrin; 2
- experimental PXRD trace of the product with that of an isostructural inclusion complex, namely the β-CD complex of 4-tert-butylbenzyl alcohol (CSD refcode KOFJEU [16]), and finding a reasonable match [20]. This procedure also enabled correct prediction of the space group (C2221) of the complex and the
- included 2ME molecule, located within the ‘cage’ provided by the well known hydrogen-bonded β-CD dimeric unit, was severely disordered and no details of its mode of inclusion could be deduced from difference electron-density syntheses. However, despite this deficiency, the inclusion complex was chemically
Size-controlled and redox-responsive supramolecular nanoparticles
Beilstein J. Org. Chem. 2015, 11, 2388–2399, doi:10.3762/bjoc.11.260
- -electron oxidation to the ferrocenium cation. At the same time, in its reduced state, Fc is a good guest for CD, but the affinity for CD is practically completely lost upon oxidation [17]. Thus, the formed CD-Fc inclusion complex disassembles when the Fc moiety is converted to the ferrocenium cation by
Co-solvation effect on the binding mode of the α-mangostin/β-cyclodextrin inclusion complex
Beilstein J. Org. Chem. 2015, 11, 2306–2317, doi:10.3762/bjoc.11.251
- in such studies may result in ternary (host:guest:co-solvent) complex formation. The objective of this work was to investigate the effect of ethanol as a co-solvent on the inclusion complex formation between α-mangostin (α-MGS) and β-CD, using both experimental and theoretical studies. Experimental
- solubility at all β-CD concentrations studied (0–10 mM). From the equilibrium constant calculation, the inclusion complex is still a binary complex (1:1), even in the presence of ethanol. The results from our theoretical study confirm that the binding mode is binary complex and the presence of ethanol as co
- -solvent enhances the solubility of α-MGS with some effects on the binding affinity with β-CD, depending on the concentration employed. Keywords: α-mangostin; β-cyclodextrin; binary complex; inclusion complex; Introduction Solubilization of otherwise poorly soluble drugs under physiological conditions to
Donor–acceptor type co-crystals of arylthio-substituted tetrathiafulvalenes and fullerenes
Beilstein J. Org. Chem. 2015, 11, 1043–1051, doi:10.3762/bjoc.11.117
- form the inclusion complex with fullerenes as well [28][29][30][31][32][33][34][35][36][37]. Very recently, we have disclosed a facile approach toward the arylthio-substituted TTFs (hereafter denoted as Ar-S-TTF) [60][61][62], which bear four aryl groups on the peripheral positions of the TTF core
Synthesis and surface grafting of a β-cyclodextrin dimer facilitating cooperative inclusion of 2,6-ANS
Beilstein J. Org. Chem. 2015, 11, 514–523, doi:10.3762/bjoc.11.58
- accessibility for inclusion-complex formation [13]. The research presented here aims to bring the cooperative effects of β-CD dimers to solid silicon dioxide surfaces. Modification of these surfaces allows the introduction of the extraordinary binding affinity and selectivity of CD dimers to silicon wafer
- negligible. Inclusion complex with free β-CD dimer in solution Host–guest interactions with the fluorescent probe 2,6-ANS were evaluated for the β-CD dimer by steady-state fluorescence spectroscopy and compared to that of the parent β-CD and 2,6-ANS. In water, 2,6-ANS displays only weak fluorescence
- -CD dimer (solid black) and 4 mM parent β-CD (dotted black). As previously mentioned, the emission spectra are affected by the polarity of the environment surrounding the 2,6-ANS, whereby a comparison of the spectra allows for evaluation of the β-CD dimer/2,6-ANS inclusion complex. From Figure 4 it is
Electrochemical oxidation of cholesterol
Beilstein J. Org. Chem. 2015, 11, 392–402, doi:10.3762/bjoc.11.45
- inclusion complex with β-cyclodextrin functionalized graphene and emerged as a cholesterol sensing matrix. Methylene blue was then replaced by the cholesterol molecule and moved out in the buffer solution, where it was detected electrochemically by using the differential pulse voltammetric technique [71
Properties of cationic monosubstituted tetraalkylammonium cyclodextrin derivatives – their stability, complexation ability in solution or when deposited on solid anionic surface
Beilstein J. Org. Chem. 2015, 11, 192–199, doi:10.3762/bjoc.11.20
- with PEMPDA-β-CD was conducted. A simple method of quantification of the extent of inclusion was developed using UV–vis spectroscopic measurements of the MeOH washes. The best results were obtained for SAL, where 34.5% of the available cavities of the PEMPDA-β-CD were in the inclusion complex form. The
- included guests in the cavities of CD anchored to the surface. For the sake of clarity we defined a new unit of measure, which describes the extent of inclusion of the guest in Nafion®-bound PEMPDA-β-CD. ROC (ratio of occupied cavities) is defined as a molar percentage of the cavities forming inclusion
- complex (Equation 1). In other words, the final number describes the percentage of the cavities saturated by the guest molecule. Here n(extr. guest) is the number of moles of guest extracted by MeOH from the Nafion®-bound PEMPDA-β-CD, n(extr. guest blank) is the number of moles of guest extracted by MeOH
Inclusion of trans-resveratrol in methylated cyclodextrins: synthesis and solid-state structures
Beilstein J. Org. Chem. 2014, 10, 3136–3151, doi:10.3762/bjoc.10.331
- of the interaction between α-CD and RSV, for example, the disappearance of the melting endotherm for RSV in the differential scanning calorimetric (DSC) trace of the product was cited as evidence for the formation of a α-CD·RSV complex [9]. The putative inclusion complex between β-CD and RSV
- complexation. It should be noted that, in general, solid-state characterization using the latter techniques is limited, the evidence for genuine inclusion complex formation not always being definitive because the preparative method may result in one or both components becoming amorphous, or an unexpected solid
- on the lack of distinct thermal events. An attempt to recrystallize the PM from MeOH/H2O (1:1 v/v) yielded a sample which displayed a distinct endo–exothermic effect in the DSC trace, attributed to inclusion complex formation. The FTIR spectrum of the KN product lacked two characteristic peaks of RSV
Release of β-galactosidase from poloxamine/α-cyclodextrin hydrogels
Beilstein J. Org. Chem. 2014, 10, 3127–3135, doi:10.3762/bjoc.10.330
- , and show sustained erosion kinetics in aqueous media. The complex was characterized by FTIR that evidenced an inclusion complex between the polyethylene oxide block and α-cyclodextrin. The release profiles of β-galactosidase from two different matrices (gels and tablets) of the in situ hydrogels have
- complex shows a new band that originates at 650 cm−1 and can be attributed to the formation of the inclusion complex between α-CD and Tetronic 90R4. For a physical mixture of Tetronic 90R4 and α-CD, the band at 650 cm−1 is not present, indicating that the inclusion complex is not formed. Analysis of the
- sample, a decrease in activity of less than 10% is found. In contrast, pure lactase enzyme loses 7% activity in that period of time. Conclusion In this study, the lactase enzyme is surrounded by the inclusion complex assemblies formed between Tetronic and α-CD, and is released from the polymer matrix
Cyclodextrin–polysaccharide-based, in situ-gelled system for ocular antifungal delivery
Beilstein J. Org. Chem. 2014, 10, 2903–2911, doi:10.3762/bjoc.10.308
- et al. [17], evaluated using NMR spectroscopy. These authors describe an inclusion complex in water with a K1:1 value of 68.7 M−1 for the β-CD:fluconazole complex and 34.6 M−1 for the HPBCD:fluconazole complex; thus, they propose, the insertion of the m-difluorophenyl ring of the drug into the wide
- , competition or promotion of the formation of the inclusion complex [18][19]. Therefore, it became necessary to study the effect of these polysaccharides on the solubility of the fluconazole–HPBCD or –SBECD complex. As can be observed in Figure 2, the addition of gellan gum or κ-carrageenan at a percentage of
- the drug across the hydrogels. This mechanism is consistent with the observed differences in the release rate due to the presence of cyclodextrin. Gels incorporating HPBCDs showed higher release rates which remained stable. Despite the fact that the formation of the inclusion complex represents only a
Synthesis and characterization of a new photoinduced switchable β-cyclodextrin dimer
Beilstein J. Org. Chem. 2014, 10, 2874–2885, doi:10.3762/bjoc.10.304
- cavities of cis-AZO-CDim 1 are complexed simultaneously by two adamantyl units of the guest forming a 1:1 complex while trans-AZO-CDim 1 seems to lead to the formation of supramolecular polymers with an n:n stoichiometry. Keywords: azobenzene; cyclodextrins; inclusion complex; photoisomerization
- ]. As an exception, Vargas et al. [29] described the synthesis of 1,2,3-triazole-linked azobenzene-cyclodextrin derivatives producing rather good yields but the photoisomerization and inclusion complex properties were not investigated. Here, we report an efficient preparation of a new bis-β-CD with
- configurations, respectively. In these conditions, using azobenzene as a linker between two β-CD can lead to a modulation of the inclusion properties, such as a cooperative effect. The cavity of each CD is available to form an inclusion complex with a hydrophobic guest molecule. Among these, adamantane is known
Synthesis of modified cyclic and acyclic dextrins and comparison of their complexation ability
Beilstein J. Org. Chem. 2014, 10, 2836–2843, doi:10.3762/bjoc.10.301
- favorably cyclic conformation and this explains the weak complex formation contrary to the smaller-sized non-cyclic analogs (G3, G4 and G5) not showing any interaction. In another study of Bettinetti et al. G7 was found to wrap up naproxen, taking on a cyclic conformation and forming a ‘pseudo’ inclusion
- complex of lower binding constant than with β-CD [6]. The helical conformations may act as ‘semicavities’ as proposed by Schurig’s group [7] who found even enantioseparation with the acetylated/silylated G6 and G7 as chiral selectors in gas chromatography. In some cases these acyclodextrins showed similar
A study on the inhibitory mechanism for cholesterol absorption by α-cyclodextrin administration
Beilstein J. Org. Chem. 2014, 10, 2827–2835, doi:10.3762/bjoc.10.300
- various effects on stabilization of fatty acids, flavor retention and emulsion formation of triglycerides via the formation of an inclusion complex [4][6][7][8]. α-CD is not used only as an encapsulation agent but also as a water-soluble dietary fiber. Furthermore, it has been reported that α-CD intake
- removes cholesterol through formation of an inclusion complex. Because α-CD is sparingly absorbed by the body [18], it is thought that α-CD acts within the lumen of the gut. Lecithin and bile salts are major cholesterol-solubilizing agents found in gallbladder bile and form mixed micelles [19][20][21
Synthesis of an organic-soluble π-conjugated [3]rotaxane via rotation of glucopyranose units in permethylated β-cyclodextrin
Beilstein J. Org. Chem. 2014, 10, 2800–2808, doi:10.3762/bjoc.10.297
- , such as an aqueous 50% methanol solution [18]. For this method, it is necessary that the molecular length of the π-conjugated guest is less than the internal diameter of the CD and similar to the depth of PMCD in order to form the self-inclusion complex (Figure 1b). When the π-conjugated guest is
- shorter than the depth of PMCD, the cross-coupling reaction is strongly inhibited because the reaction has to occur in the PMCD cavity (Figure 1a). On the other hand, a self-inclusion complex does not form if the guest is longer than the internal diameter of PMCD (Figure 1c). Thus far, we have succeeded
- increasing the hydrophilicity of the solvent, the formation of double inclusion complex 6 predominated. When we added D2O in order to increase hydrophilicity, the exclusion complex completely converted into inclusion complex 6 in CD3OD:D2O = 1:1 solutions. To synthesize an organic-soluble linked [3]rotaxane
Binding mode and free energy prediction of fisetin/β-cyclodextrin inclusion complexes
Beilstein J. Org. Chem. 2014, 10, 2789–2799, doi:10.3762/bjoc.10.296
- applications, β-CD has been mostly used as a drug carrier, stabilizer and additive by the formation of host–guest complexes with increased solubility and consequently better bioavailability of low water soluble organic compounds (i.e., drugs) [20][21][22][23]. The inclusion complex can also improve ligand
- these two previous studies, the fisetin/β-CD inclusion complex was optimized in gas phase, the A- or B-rings of fisetin were not well inserted, but only partially occupied in the cavity, while the other ring entirely stayed outside of the β-CD moiety. Herein, the host–guest inclusion complexation
- inclusion complex. The ligand binding mode and water accessibility, host–guest interaction, and binding free energy of the inclusion complex were analyzed. The MM-PBSA/GBSA and M06-2X/6-31G(d,p)//MM-PBSA/GBSA approaches were used to predict the binding affinity of fisetin/β-CD complexes. The M06-2X/6-31G(d
Removal of volatile organic compounds using amphiphilic cyclodextrin-coated polypropylene
Beilstein J. Org. Chem. 2014, 10, 2743–2750, doi:10.3762/bjoc.10.290
- 60/40 [21]. However, if for some reason the cavities of the ACDs are inaccessible for inclusion complex formation, it would not be cost-efficient to simply focus on obtaining the maximum coating amount. For this reason, the uptake capacity of the coating obtained from a coating solutions of ethanol
- , see Figure 1. It is known that one of the driving forces in inclusion complex formation in water between CDs (the host) and the included compound (the guest) is the hydrophobicity of the guest [7]. Hence, there is an inherent tendency towards the formation of inclusion complexes with 5 in comparison
- VOCs would result in even higher stoichiometries. However, a stoichiometry of even 6:1 for β-CD:benzene/benzene derivatives is, of course, not caused by inclusion complex formation alone, as that would be physically impossible. The large uptake capacity of the coated PP must, therefore, be caused by
Anomalous diffusion of Ibuprofen in cyclodextrin nanosponge hydrogels: an HRMAS NMR study
Beilstein J. Org. Chem. 2014, 10, 2715–2723, doi:10.3762/bjoc.10.286
- nanosponge gels. Conversely, significant doubling of selected aromatic and methyl protons of IP was reported to take place in the presence of monomeric β-CD in D2O solution, thus confirming, in that case, the formation of an inclusion complex and the chiral discrimination [28]. The absence of signal doubling
Improving ITC studies of cyclodextrin inclusion compounds by global analysis of conventional and non-conventional experiments
Beilstein J. Org. Chem. 2014, 10, 2630–2641, doi:10.3762/bjoc.10.275
- methods may be of valuable aid. We observed this kind of behavior when the studied inclusion complex is nearly athermic (inclusion enthalpy close to 0 cal·mol−1). For example, this is the case for the HPβ-CD-IBU complex at 283 K: under these conditions, titration and release signals are not significantly
Synthesis of a resin monomer-soluble polyrotaxane crosslinker containing cleavable end groups
Beilstein J. Org. Chem. 2014, 10, 2623–2629, doi:10.3762/bjoc.10.274
- an inclusion complex of PEG with ca. 50 α-CDs. The degradation nature of C12-Bu12-MA12 was confirmed after the treatment with DTT. As shown in Figure 3, the PRX SEC signal almost disappeared, and a large intensity of low molecular weight signals was observed within 40–50 min. The low molecular weight
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