Particle size effect in the mechanically assisted synthesis of β-cyclodextrin mesitylene sulfonate

• Stéphane Menuel,
• Sébastien Saitzek,
• Eric Monflier and
• Frédéric Hapiot

Beilstein J. Org. Chem. 2020, 16, 2598–2606, doi:10.3762/bjoc.16.211

• to be a non-interactive guest towards the CD host [18], meaning that no inclusion compounds could be formed during the course of the reaction. Previous works dealing with this reaction showed that β-CDMts featuring a defined number of mesitylenesulfonate groups could be obtained selectively in

Crystal structure of the inclusion complex of cholesterol in β-cyclodextrin and molecular dynamics studies

• Elias Christoforides,
• Andreas Papaioannou and
• Kostas Bethanis

Beilstein J. Org. Chem. 2018, 14, 838–848, doi:10.3762/bjoc.14.69

• in the case that one of the cell dimensions is more than 17 Å the two others being also about 15.5 Å. The Cambridge Structural Database (CSD) [32] search resulted in 26 structures of inclusion compounds in β-CD with similar cell dimensions. Among them, three entries (ANAXAP [33], UJEFEV [34] and

Structural diversity in the host–guest complexes of the antifolate pemetrexed with native cyclodextrins: gas phase, solution and solid state studies

• Magdalena Ceborska,
• Magdalena Zimnicka,
• Aneta Aniela Kowalska,
• Kajetan Dąbrowa and
• Barbara Repeć

Beilstein J. Org. Chem. 2017, 13, 2252–2263, doi:10.3762/bjoc.13.222

• for the analogous γ-CD/FA complex, both regarding the architecture and the strength of the obtained inclusion compounds. Studies of PTX complexes in the solid state FTIR–ATR The FTIR spectra of CDs/PTX complexes may be divided into three regions (Supporting Information File 1, Figure S25, and Table S8

Superstructures with cyclodextrins: Chemistry and applications IV

• Gerhard Wenz

Beilstein J. Org. Chem. 2017, 13, 2157–2159, doi:10.3762/bjoc.13.215

• repulsive. The first examples of superstructures formed by attractive intermolecular forces were complexes of crown ethers [1], cryptands [2] and spherands [3], which were recognized by the 1987 Nobel Prize in Chemistry. In addition, inclusion compounds of cyclodextrins (CDs), cyclic oligomers of glucose

Solid-state studies and antioxidant properties of the γ-cyclodextrin·fisetin inclusion compound

• Joana M. Pais,
• Maria João Barroca,
• Maria Paula M. Marques,
• Filipe A. Almeida Paz and
• Susana S. Braga

Beilstein J. Org. Chem. 2017, 13, 2138–2145, doi:10.3762/bjoc.13.212

• between the diffraction envelope of the recrystallized γ-CD·fisetin and the diffractogram calculated from the atomic coordinates of a model inclusion complex, γ-CD–12-crown-4 ether (trace (d) in Figure 1) [31]. Such a match, according to Caira’s systematization of crystalline CD inclusion compounds [30

• packing, a structure occurring frequently in solid γ-CD inclusion compounds. The results from the DPPH scavenging assay show that the antioxidant activity of fisetin is retained upon inclusion, thus making the γ-CD·fisetin inclusion compound a suitable additive for food fortification or health supplements

Supramolecular polymer assembly in aqueous solution arising from cyclodextrin host–guest complexation

• Jie Wang,
• Zhiqiang Qiu,
• Yiming Wang,
• Li Li,
• Xuhong Guo,
• Duc-Truc Pham,
• Stephen F. Lincoln and
• Robert K. Prud’homme

Beilstein J. Org. Chem. 2016, 12, 50–72, doi:10.3762/bjoc.12.7

• complexes hydrophobic guest species to form host–guest complexes, or inclusion compounds. The host–guest complexes formed by cyclodextrins and their hydrophobic guests, which range from small molecules to polymer substituents and sections of polymer chains, have been widely studied and utilized as building

Inclusion complexes of 2-methoxyestradiol with dimethylated and permethylated β-cyclodextrins: models for cyclodextrin–steroid interaction

• Mino R. Caira,
• Susan A. Bourne,
• Halima Samsodien and
• Vincent J. Smith

Beilstein J. Org. Chem. 2015, 11, 2616–2630, doi:10.3762/bjoc.11.281

• DU® 640 series UV–vis spectrophotometer operating at a scan rate of 1200 nm/min over the range 190–450 nm with solutions for analysis placed in 2 mm quartz cuvettes. For CD inclusion compounds of 2ME, host–guest stoichiometries were determined at the absorption maximum for the bioactive compound

Co-solvation effect on the binding mode of the α-mangostin/β-cyclodextrin inclusion complex

• Chompoonut Rungnim,
• Sarunya Phunpee,
• Manaschai Kunaseth,
• Supawadee Namuangruk,
• Kanin Rungsardthong,
• Thanyada Rungrotmongkol and
• Uracha Ruktanonchai

Beilstein J. Org. Chem. 2015, 11, 2306–2317, doi:10.3762/bjoc.11.251

• the β-CD structure and guest molecules in its inclusion compounds have been reported [19][20][21]. Moreover, MD simulations of β-CD in water and ethanol mixtures have been performed to investigate the orientation of the co-solvent in the hydrophobic cavity of the β-CD [22]. Recently, Biedermann et al

Superstructures with cyclodextrins: Chemistry and applications II

• Gerhard Wenz

Beilstein J. Org. Chem. 2015, 11, 271–272, doi:10.3762/bjoc.11.30

• ]. Many other applications are certain to follow. The 17th International Cyclodextrin Symposium, held in May 2014 in Saarbrücken, Germany provided an overview of the various aspects of CD chemistry, such as organic synthesis, analysis of inclusion compounds, polymeric and colloidal systems, as well as

Inclusion of trans-resveratrol in methylated cyclodextrins: synthesis and solid-state structures

• Lee Trollope,
• Dyanne L. Cruickshank,
• Terence Noonan,
• Susan A. Bourne,
• Milena Sorrenti,
• Laura Catenacci and
• Mino R. Caira

Beilstein J. Org. Chem. 2014, 10, 3136–3151, doi:10.3762/bjoc.10.331

• , permethylated β-CD and 2,6-dimethylated β-CD) are described. Isolation of the corresponding crystalline 1:1 inclusion compounds enabled their full structure determination by X-ray analysis for the first time, revealing a variety of guest inclusion modes and unique supramolecular crystal packing motifs. The

• phase (e.g., a hydrate of the guest compound) might be generated during attempted complexation. Loss of crystallinity of CD inclusion compounds also results when they dehydrate, rendering their PXRD traces less informative. There is, hitherto, a distinct lack of information on the structural nature of

• inclusion compounds as single crystals enabled their complete structural elucidation, revealing several novel supramolecular features which are relevant for future studies of the antioxidant RSV. Availability of well-defined, crystalline inclusion complexes also ensured that their characterization using

Release of β-galactosidase from poloxamine/α-cyclodextrin hydrogels

• César A. Estévez,
• José Ramón Isasi,
• Eneko Larrañeta and
• Itziar Vélaz

Beilstein J. Org. Chem. 2014, 10, 3127–3135, doi:10.3762/bjoc.10.330

• are able to form host–guest complexes by the inclusion of hydrophobic molecules. Cyclodextrins also act as hosts in the formation of inclusion compounds with polymer chains through non-covalent interactions [10]. For instance, incorporation of 5% α-CD transforms dilute Tetronic solutions into gels

Conjugates of methylated cyclodextrin derivatives and hydroxyethyl starch (HES): Synthesis, cytotoxicity and inclusion of anaesthetic actives

• Lisa Markenstein,
• Antje Appelt-Menzel,
• Marco Metzger and
• Gerhard Wenz

Beilstein J. Org. Chem. 2014, 10, 3087–3096, doi:10.3762/bjoc.10.325

• forms inclusion compounds with derivatives of benzene, naphthalene, adamantane, and many other moieties of similar sizes [3]. Applications of β-CD as complexing agents are limited because of low aqueous solubilities of β-CD and its complexes. Furthermore, the toxic potential of β-CD is known for a long

Synthesis of uniform cyclodextrin thioethers to transport hydrophobic drugs

• Lisa F. Becker,
• Dennis H. Schwarz and
• Gerhard Wenz

Beilstein J. Org. Chem. 2014, 10, 2920–2927, doi:10.3762/bjoc.10.310

• the β-cyclodextrin derivatives exhibit very high binding potentials towards the anaesthetic drugs sevoflurane and halothane. Since the resulting inclusion compounds are highly soluble in water at temperatures ≤37 °C they are good candidates for new aqueous dosage forms which would avoid inhalation

• solubility of the formed inclusion compounds. As a consequence, the phase solubility isotherm shows saturation behaviour, so-called B-type curves [11][12]. Therefore many CD derivatives have been synthesized to overcome this problem [1][12][13]. Statistical β-CD derivatives, such as hydroxypropyl-β-CD [14

Improving ITC studies of cyclodextrin inclusion compounds by global analysis of conventional and non-conventional experiments

• Eléonore Bertaut and
• David Landy

Beilstein J. Org. Chem. 2014, 10, 2630–2641, doi:10.3762/bjoc.10.275

• Eleonore Bertaut David Landy Univ Lille Nord de France, F-59000 Lille, France ULCO, UCEIV, F-59140 Dunkerque, France 10.3762/bjoc.10.275 Abstract The study of 1:1 cyclodextrin inclusion compounds by isothermal titration calorimetry was explored in a theoretical and experimental point of view to

• stability, enthalpy, or solubility. Keywords: cyclodextrins; global analysis; inclusion compounds; isothermal titration calorimetry; non-conventional experiments; Introduction The stability and thermodynamics of cyclodextrin inclusion compounds in solutions may be investigated with various analytical

• -conventional ITC protocols. This work aims for the description of the whole conventional and non-conventional ITC experiments within the cyclodextrin context and the evaluation of the resulting accuracy on thermodynamic parameters of inclusion compounds. For this purpose, we successfully applied a unified

Topochemical control of the photodimerization of aromatic compounds by γ-cyclodextrin thioethers in aqueous solution

• Hai Ming Wang and
• Gerhard Wenz

Beilstein J. Org. Chem. 2013, 9, 1858–1866, doi:10.3762/bjoc.9.217

• only improves the quantum yields of photodimerizations but also gives rise to high regio- and stereo-selectivities [15][16][17][18] However, the application of native CDs for fully hydrophobic reactants is hampered by the fact that their inclusion compounds are nearly insoluble in water leading to

• paid to both the quantum yields Φ and stereoselectivities of the photodimerizations. Results and Discussion Photodimerization of anthracene Due to the fact that the inclusion compounds of ANT in native β-CD or γ-CD are completely insoluble in water, only the aqueous photochemistry of hydrophilic ANT

• Pd nanocage [33] in aqueous solution, both giving rise to the exclusive formation of the syn isomer. Unfortunately, the quantum yields have not been reported for these systems so far. ACE also formed inclusion compounds with β-CD thioethers 1–7, which are soluble in aqueous medium. The highest

Structures of the reaction products of the AZADO radical with TCNQF₄ or thiourea

• Hideto Suzuki,
• Yuta Kawahara,
• Hiroki Akutsu,
• Jun-ichi Yamada and
• Shin’ichi Nakatsuji

Beilstein J. Org. Chem. 2013, 9, 1487–1491, doi:10.3762/bjoc.9.169

• acceptor. Moreover, we tried to prepare a supramolecule from 2 with thiourea (4), as structurally similar 1-bromoadamantane was reported to form an intriguing inclusion compound with thiouea [9]. There are some reported examples of inclusion compounds derived from TEMPO and related nitroxide radicals with

• the reaction product of AZADO and thiourea We next tried to perform the reaction of AZADO (2) with thiourea (4) to see if some intriguing complexes would be formed, since a lot of inclusion compounds derived from urea or thiourea are known [13]. The reaction between 2 and 4 was first tried by mixing

• reported to be 1:4 [9]. As usually seen in thiourea-derived inclusion compounds, the thiourea channels are formed by hydrogen bonds between the amino-hydrogen atoms and thiocarbonyl groups of neighbouring thiourea molecules to interlock honeycomb-type structures. There exist apparent short contacts of 3.06

Space filling of β-cyclodextrin and β-cyclodextrin derivatives by volatile hydrophobic guests

• Sophie Fourmentin,
• Anca Ciobanu,
• David Landy and
• Gerhard Wenz

Beilstein J. Org. Chem. 2013, 9, 1185–1191, doi:10.3762/bjoc.9.133

• pressure; Introduction β-Cyclodextrin (β-CD, 1), the cyclic α(1→4) heptamer of glucose, is known to form inclusion compounds with a great variety of guests [1], such as derivatives of benzene [2][3], cyclohexane [4], adamantane [5][6], other alicyclic guests [7], and also inorganic molecules or ions [1][8

• delivery [18][19], extraction of pollutants from soil [20][21][22][23], homogenous catalysis [24], and microbial degradation [25] are limited by both its low aqueous solubility (1.8 wt % at 25°C) and its moderate complexing ability. Especially hydrophobic guests form channel inclusion compounds with β-CD

• gas chromatography (HS-GC) is a highly sensitive technique, it allows the investigation of the complexation of volatile guests in CD at very low concentrations, where guests, as well as their inclusion compounds, are still soluble in water [19][34][35][36]. Complexation of a guest is detected

Theoretical study on β-cyclodextrin inclusion complexes with propiconazole and protonated propiconazole

• Adrian Fifere,
• Narcisa Marangoci,
• Stelian Maier,
• Adina Coroaba,
• Dan Maftei and
• Mariana Pinteala

Beilstein J. Org. Chem. 2012, 8, 2191–2201, doi:10.3762/bjoc.8.247

• methods, such as CNDO, AM1 and PM3 were widely used in the theoretical investigation of CDs. The PM3 method has proved to be a powerful tool in the conformational study of supramolecular systems, such as CD inclusion compounds and provides better performance compared to the AM1 method for molecular

• in tandem with the semi-empirical PM3 method [13][14][15][16][17]. Because of the experimental limitations, the geometric details and the interactions that stabilize the molecular architecture of β-CD/PPH+ inclusion compounds are still poorly understood. For this reason the present study

• + inclusion compounds were selected by considering the binding energy as being the difference between the heat of formation of the complex and the heat of formation of the involved free molecules: where ECD/PP, EPP and ECD represent the heat of formation of the complex, of the free β-CD, and of the free guest

Influence of intramolecular hydrogen bonds on the binding potential of methylated β-cyclodextrin derivatives

• Gerhard Wenz

Beilstein J. Org. Chem. 2012, 8, 1890–1895, doi:10.3762/bjoc.8.218

• ]. The host–guest complexes, so-called cyclodextrin inclusion compounds, find many applications such as solubilization of pharmaceutical drugs, dispersion of cosmetics, catalysis, or chromatographic separation of enantiomers [2][7][8]. Application of β-CD 1 is hampered by its low solubility of 18.8 g L−1

• at 25 °C [9]. Solubility of β-CD and its inclusion compounds can be significantly increased by the covalent attachment of neutral or ionic substituents [10]. Methylated β-CDs, such as heptakis(2,6-di-O-methyl)-β-CD 2 and heptakis (2,3,6-tri-O-methyl)-β-CD 3, are well known for their high solubilities

Molecular solubilization of fullerene C₆₀ in water by γ-cyclodextrin thioethers

• Hai Ming Wang and
• Gerhard Wenz

Beilstein J. Org. Chem. 2012, 8, 1644–1651, doi:10.3762/bjoc.8.188

• dissolution of C60 by γ-CD thioethers, because they also did not improve the solubilization process significantly. Investigation of aggregation by dynamic light scattering Since aggregation of CDs and CD inclusion compounds was already found in previous work [44][45], dynamic light scattering (DLS

Restructuring polymers via nanoconfinement and subsequent release

• Alan E. Tonelli

Beilstein J. Org. Chem. 2012, 8, 1318–1332, doi:10.3762/bjoc.8.151

• ; inclusion compounds; nanoconfinement; organization; polymers; properties; release; urea; Introduction The behaviors and properties of polymer materials are closely related to the organizations, structures, and morphologies of their constituent chains, which can be significantly altered during their

• demonstrate the utility of restructuring polymers, through nanoconfinement in and subsequent release/coalescence from their noncovalently bonded inclusion compounds, for the reorganization of their resulting bulk samples, thereby improving their properties. Because c-polymers remain reorganized despite long

Molecular recognition of organic ammonium ions in solution using synthetic receptors

• Andreas Späth and
• Burkhard König

Beilstein J. Org. Chem. 2010, 6, No. 32, doi:10.3762/bjoc.6.32