Dynamics and interactions of ibuprofen in cyclodextrin nanosponges by solid-state NMR spectroscopy

• Monica Ferro,
• Franca Castiglione,
• Nadia Pastori,
• Carlo Punta,
• Lucio Melone,
• Walter Panzeri,
• Barbara Rossi,
• Francesco Trotta and
• Andrea Mele

Beilstein J. Org. Chem. 2017, 13, 182–194, doi:10.3762/bjoc.13.21

• loading, thus providing a dynamic fingerprint of the formation of a supramolecular architecture. The latter is characterized by the formation of IbuH domanins in the pores of the 3D structure of the polymeric network. The experimental data show that the inclusion of IbuH in the CD cavity – namely the

• formation of a host–guest inclusion complex – does not occur, confirming the situation already described by HR-MAS NMR data for the same system in the gel state [9] and outlining a different scenario on passing from monomeric CD, capable to form well characterized inclusion complexes with IbuH [29][30][31

• -mono-6-amino-6-deoxy-β-CD (GMA-NH2-β-CD) co-polymerized with ethylene dimethacrylate [32]. The corresponding cross-linked polymers are thus decorated with cyclodextrin units, easily accessible to small molecules to give rise to inclusion complexes. This type of polymers showed excellent efficiency as

Total synthesis of a Streptococcus pneumoniae serotype 12F CPS repeating unit hexasaccharide

• Peter H. Seeberger,
• Claney L. Pereira and
• Subramanian Govindan

Beilstein J. Org. Chem. 2017, 13, 164–173, doi:10.3762/bjoc.13.19

• immunological analysis of S. pneumoniae serotype 12F can be undertaken, and future work will address the expanded inclusion of this antigen in next-generation glycoconjugate vaccines. Abbreviations Ac: acetate ester; BAIB: bis(acetoxy)iodobenzene; Bz: benzoyl; CPS: capsular polysaccharide; DMF: N,N

A new class of organogelators based on triphenylmethyl derivatives of primary alcohols: hydrophobic interactions alone can mediate gelation

• Wangkhem P. Singh and
• Rajkumar S. Singh

Beilstein J. Org. Chem. 2017, 13, 138–149, doi:10.3762/bjoc.13.17

• ][21][22]. As mentioned above, developing a new gelator is still largely a trial and error method. The most widely used design strategy involves the inclusion of structural components favouring intermolecular non-covalent interactions (like H-bonding, π-stacking, donor–acceptor interaction, metal

Phosphated cyclodextrins as water-soluble chiral NMR solvating agents for cationic compounds

• Cira Mollings Puentes and
• Thomas J. Wenzel

Beilstein J. Org. Chem. 2017, 13, 43–53, doi:10.3762/bjoc.13.6

• inclusion complexes with CDs and the differing sizes of α-, β- and γ-CD allow the study of substrates of different sizes. Furthermore, the secondary hydroxy groups at the 2 and 3-positions and the primary hydroxy groups at the 6-position of CDs can be derivatized with a variety of functional groups. Such

• that at the primary side. Native, underivatized CDs are effective chiral NMR solvating agents in water [8][9]. Water-soluble substrates with hydrophobic moieties such as aryl rings typically form inclusion complexes by insertion of the aryl ring into the CD cavity. Neutral CDs with permethylated [10

• -containing compounds form inclusion complexes more favorably with the larger β- and γ-cyclodextrins so the general ineffectiveness of P-α-CD-LDS and P-α-CD-HDS for 27–29 is not surprising (Table 5). Both the P-β-CDs and P-γ-CDs are effective at causing enantiomeric differentiation in resonances of 27–29. An

Synthesis of multi-lactose-appended β-cyclodextrin and its cholesterol-lowering effects in Niemann–Pick type C disease-like HepG2 cells

• Keiichi Motoyama,
• Rena Nishiyama,
• Yuki Maeda,
• Taishi Higashi,
• Yoichi Ishitsuka,
• Yuki Kondo,
• Tetsumi Irie,
• Takumi Era and
• Hidetoshi Arima

Beilstein J. Org. Chem. 2017, 13, 10–18, doi:10.3762/bjoc.13.2

• cholesterol [25]. NPC2 interacts with NPC1 and delivers cholesterol to the limiting membranes [25], while β-CDs form inclusion complexes with cholesterol. Hence, β-CDs may have the potential to bypass the functional NPC1 or NPC2 and deliver cholesterol directly to the limiting membranes. Once the cholesterol

Versatile synthesis of end-reactive polyrotaxanes applicable to fabrication of supramolecular biomaterials

• Atsushi Tamura,
• Asato Tonegawa,
• Yoshinori Arisaka and
• Nobuhiko Yui

Beilstein J. Org. Chem. 2016, 12, 2883–2892, doi:10.3762/bjoc.12.287

• functional PRXs and can be applied to the fabrication of PRX-based supramolecular biomaterials. Keywords: azide group; biomaterials; click chemistry; cyclodextrin; polyrotaxane; Introduction Polyrotaxanes (PRXs) are a class of interlocked polymers that consist of an inclusion complex of cyclodextrins (CDs

• the terminals of the axle polymers have an attractive designs for the fabrication of biomaterials, because the terminal azide or alkynyl groups in the PRXs can be utilized for the modification of other polymer chains and functional molecules. In general, PRXs comprising an inclusion complex of a

Stabilization of nanosized titanium dioxide by cyclodextrin polymers and its photocatalytic effect on the degradation of wastewater pollutants

• Tamás Zoltán Agócs,
• István Puskás,
• Erzsébet Varga,
• Mónika Molnár and
• Éva Fenyvesi

Beilstein J. Org. Chem. 2016, 12, 2873–2882, doi:10.3762/bjoc.12.286

• pollutant of emerging concern (EP), was protected by CMBCD-P against the photocatalytic degradation showing that inclusion complex formation can result in opposite effects depending on the structure of the host–guest complex. Keywords: carboxymethyl β-cyclodextrin polymer; colloid stability; ibuprofen

• oligosaccharides consisting of 6–8 glucose units (α-, β- and γ-CD) primarily used in the pharmaceutical, cosmetic and household chemical industry [8]. They form non-covalent inclusion complexes with a great number of the organic contaminants in soil (petroleum hydrocarbons, polycyclic aromatic hydrocarbons, etc

• when linked to nanoTiO2 colloids leading to restriction of charge–hole recombination [35]. The efficiency is further improved by keeping the ligands close to the surface of nanoTiO2 via inclusion complexation. In other studies the presence of CDs caused a delay in the photocatalytic degradation of

Characterization of the synthetic cannabinoid MDMB-CHMCZCA

• Carina Weber,
• Stefan Pusch,
• Dieter Schollmeyer,
• Sascha Münster-Müller,
• Michael Pütz and
• Till Opatz

Beilstein J. Org. Chem. 2016, 12, 2808–2815, doi:10.3762/bjoc.12.279

• inclusion of diffuse functions (def2-TZVPP vs ma-def2-TZVPP). The use of the range-separated (long-range corrected) CAM-B3LYP and ωB97XD functionals – probably more appropriate for the description of charge-transfer states – also did not lead to an improvement of the data. On the other hand, an assignment

Interactions between cyclodextrins and cellular components: Towards greener medical applications?

• Loïc Leclercq

Beilstein J. Org. Chem. 2016, 12, 2644–2662, doi:10.3762/bjoc.12.261

• by inclusion into their hydrophobic cavity, they have been widespread used to develop numerous pharmaceutical formulations. Nevertheless, CDs are also able to interact with endogenous substances that originate from an organism, tissue or cell. These interactions can be useful for a vast array of

• reviewed as well as their interactions with isolated biomolecules leading to the formation of inclusion or exclusion complexes. Finally, some potential medical applications are highlighted throughout several examples. Keywords: cellular interactions; cyclodextrins; endogenous substances; extraction

• great variety of modified CDs has been developed to improve the stability and the solubility of inclusion complexes [8][9][10]. Nowadays, CDs are widely applied in many fields [11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28] due to their host–guest properties, their origins

Effects of solvent additive on “s-shaped” curves in solution-processed small molecule solar cells

• John A. Love,
• Shu-Hua Chou,
• Ye Huang,
• Guilllermo C. Bazan and
• Thuc-Quyen Nguyen

Beilstein J. Org. Chem. 2016, 12, 2543–2555, doi:10.3762/bjoc.12.249

• prove the hypothesis that the root of s-shaped J–V curves was indeed non-ideal vertical phase separation. Conclusion A new molecular donor material, p-SIDT(FBTThCA8)2, was developed based on the inclusion of electron-withdrawing endcaps within a previously reported high-performance molecular framework

• inclusion of DIO helps to reduce the concentration of PC71BM at the anode improving surface recombination, and J–V characteristics. This is further evidenced by the elimination of the s-kink upon moving to an inverted structure. In fact, in the inverted structure the blend device gives a VOC of 1.09 V

A self-assembled cyclodextrin nanocarrier for photoreactive squaraine

• Ulrike Kauscher and
• Bart Jan Ravoo

Beilstein J. Org. Chem. 2016, 12, 2535–2542, doi:10.3762/bjoc.12.248

• aqueous solution of the vesicle [30]. The hydrophobic cyclodextrin cavities are well known to form size-selective inclusion complexes with apolar compounds such as adamantane [31]. In several publications, we have shown that CDVs retain this ability by keeping the cavity available for host–guest

• inclusion between the adamantane groups and the cyclodextrin cavities at the surface of cyclodextrin vesicles (CDVs) results in efficient immobilization of the squaraine on a nanocarrier. In addition, π–π stacking (and hence inactivation) of the squaraine is supressed due to the steric separation of the

Radical polymerization by a supramolecular catalyst: cyclodextrin with a RAFT reagent

• Kohei Koyanagi,
• Yoshinori Takashima,
• Takashi Nakamura,
• Hiroyasu Yamaguchi and
• Akira Harada

Beilstein J. Org. Chem. 2016, 12, 2495–2502, doi:10.3762/bjoc.12.244

• in water was significantly low, leading to the formation of precipitates. β-CD-CTA forms a self-inclusion complex or a supramolecular dimer complex, which was characterized using 2D ROESY NMR (Supporting Information File 1, Figure S4). We focused on the polymerization activity of α-CD-CTA because the

• inhibiting the molecular recognition of α-CD, the inclusion complexation ratio between the monomer and α-CD-CTA was decreased, which lead to lower yields and higher molecular weight of the resulting polymers due to preceding free radical polymerization. In the reaction of AAm monomer, which has a low

• the growing polymer chain, and exploring its function mimicking a biological molecular clamp. Preparation scheme of α-CD-CTA. Crystal structure of α-CD with N,N-dimethylacrylamide (DMA). (a) The structure of an 1:1 inclusion complex between α-CD and DMA. One of the disordered pattern of DMA is shown

Efficient mechanochemical synthesis of regioselective persubstituted cyclodextrins

• Laszlo Jicsinszky,
• Marina Caporaso,
• Katia Martina,
• Emanuela Calcio Gaudino and
• Giancarlo Cravotto

Beilstein J. Org. Chem. 2016, 12, 2364–2371, doi:10.3762/bjoc.12.230

• most noted for their ability to form non-covalent associations called “inclusion complexes”. Natural CDs exhibit many favourable properties, which advance their use in a wide range of applications. However, syntheses for many special applications, such as DNA sequencing [4][5], gene delivery [6], and

• because of the high boiling polar aprotic solvents used; their complete removal is a difficult task under laboratory conditions, even at high vacuum. Ball milling is an effective method for the preparation of inclusion complexes which has recently begun to be appreciated by organic chemists for its

High performance p-type molecular electron donors for OPV applications via alkylthiophene catenation chromophore extension

• Paul B. Geraghty,
• Calvin Lee,
• Jegadesan Subbiah,
• Wallace W. H. Wong,
• James L. Banal,
• Mohammed A. Jameel,
• Trevor A. Smith and
• David J. Jones

Beilstein J. Org. Chem. 2016, 12, 2298–2314, doi:10.3762/bjoc.12.223

• =17.23 mA cm−2, FF 63.42%, Voc of 0.793 V, and a PCE 8.81%, 1:1.5 PTB7-Th:PC71BM). Inclusion of 15 wt % of BQR in the donor phase resulted in a significantly enhanced efficiency from 9.6% to 10.7% PCE, with increase in the device Jsc to 19.8 mA cm–2, while the Voc and FF remain effectively unchanged. To

• between 500–600 nm comparing to the binary blend (PTB7-Th:PC71BM). This enhanced absorption in the ternary blend is due to the inclusion of BQR as confirmed from the absorption spectrum of BQR: PC71BM, which shows the absorption maximum in the wavelength range 500–600 nm. Further device optimization and

Thiophene-forming one-pot synthesis of three thienyl-bridged oligophenothiazines and their electronic properties

• Dominik Urselmann,
• Konstantin Deilhof,
• Bernhard Mayer and
• Thomas J. J. Müller

Beilstein J. Org. Chem. 2016, 12, 2055–2064, doi:10.3762/bjoc.12.194

• the 13C NMR spectra additionally supported the assigned structures. Combustion analyses of compounds 3b and 3c indicate that water and THF (compound 3b) and water (compound 3c) are present as solvent inclusion in the resins that cannot be removed even upon extensive drying under vacuo. However, HPLC

Potent triazine-based dehydrocondensing reagents substituted by an amido group

• Munetaka Kunishima,
• Daiki Kato,
• Nobu Kimura,
• Masanori Kitamura,
• Kohei Yamada and
• Kazuhito Hioki

Beilstein J. Org. Chem. 2016, 12, 1897–1903, doi:10.3762/bjoc.12.179

• reactivity of triazine was found to slightly increase following the introduction of electron-withdrawing phenoxy or 2,2,2-trifluoroethoxy groups and decrease upon the inclusion of an electron-donating N-ethylamino group. This result may indicate that the tuning of the π-electron density within the triazine

Cross-linked cyclodextrin-based material for treatment of metals and organic substances present in industrial discharge waters

• Élise Euvrard,
• Nadia Morin-Crini,
• Coline Druart,
• Justine Bugnet,
• Bernard Martel,
• Cesare Cosentino,
• Virginie Moutarlier and
• Grégorio Crini

Beilstein J. Org. Chem. 2016, 12, 1826–1838, doi:10.3762/bjoc.12.172

• groups and CD cavities, the adsorption mechanism involves four main interactions: ion exchange, electrostatic interactions and precipitation for metal removal, and inclusion complexes for organics removal. In industrial discharge waters, competition effects appeared, especially because of the presence of

• material was initially activated by NaHCO3. Discussion To explain the adsorption performance of polyBTCA-CD, a chemisorption mechanism involving several interactions can occur including ion exchange, electrostatic interactions, inclusion complexation and/or precipitation [3][12][13][14][15][16]. The

• inclusion complexes with PAH guest molecules (organic substances) [3][20]. If the guest compounds present an appropriate molecular size and structure to enter into the CD cavity the more hydrophobic the organic substances, the more stable the inclusion complexes. The material was also able to efficiently

Selective bromochlorination of a homoallylic alcohol for the total synthesis of (−)-anverene

• Frederick J. Seidl and
• Noah Z. Burns

Beilstein J. Org. Chem. 2016, 12, 1361–1365, doi:10.3762/bjoc.12.129

• . In the subsequent optimization, three critical factors came to the fore: concentration, the inclusion of additional Ti(OiPr)4, and stirring rate. When unoptimized bromochlorination reactions of homoprenol were quenched at low and high conversion, different distributions of side products were obtained

• efficient and selective synthesis of 1 via homoprenol bromochloride 6. The factors addressed in the optimization of the bromochlorination for homoprenol, namely concentration, the inclusion of additional Ti(OiPr)4, and vigorous stirring, are expected to be generally important to other challenging substrates

Efficient syntheses of climate relevant isoprene nitrates and (1R,5S)-(−)-myrtenol nitrate

• Sean P. Bew,
• Glyn D. Hiatt-Gipson,
• Graham P. Mills and
• Claire E. Reeves

Beilstein J. Org. Chem. 2016, 12, 1081–1095, doi:10.3762/bjoc.12.103

• bromide (56), we envisaged its subsequent deprotonation and addition to chloroacetone would afford (E)-1-((2-methyl-4-chlorobut-2-enyloxy)methyl)-4-methoxybenzene (57). Inclusion of the PMB-ether was beneficial due to the ease with which it can be cleaved using readily available reagents, e.g., DDQ or CAN

Cationic Pd(II)-catalyzed C–H activation/cross-coupling reactions at room temperature: synthetic and mechanistic studies

• Takashi Nishikata,
• Alexander R. Abela,
• Shenlin Huang and
• Bruce H. Lipshutz

Beilstein J. Org. Chem. 2016, 12, 1040–1064, doi:10.3762/bjoc.12.99

• transformations. Three approaches (Figure 1) have generally been employed to enhance the reactivity and promote the key metalation/C–H bond cleavage step: (1) tuning of the reaction conditions through inclusion of various additives such as metal salts [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18

Strecker degradation of amino acids promoted by a camphor-derived sulfonamide

• M. Fernanda N. N. Carvalho,
• M. João Ferreira,
• Ana S. O. Knittel,
• Maria da Conceição Oliveira,
• João Costa Pessoa,
• Rudolf Herrmann and
• Gabriele Wagner

Beilstein J. Org. Chem. 2016, 12, 732–744, doi:10.3762/bjoc.12.73

• is an obvious candidate as catalyst. Indeed, water inclusion in reaction paths with high-lying transition states is often observed in water as solvent, as in biochemical reactions, and was demonstrated for, e.g., the analytical detection of sulfenic acids with dimedone [36]. In these systems water

Creating molecular macrocycles for anion recognition

• Amar H. Flood

Beilstein J. Org. Chem. 2016, 12, 611–627, doi:10.3762/bjoc.12.60

• signature for the TBA+ cation’s α proton showed a lower diffusion coefficient at 1 equiv when it forms the larger ion pair complex MC·Cl−·TBA+. Ultimately, any accurate assessment of an equilibrium constant requires inclusion of all the equilibria. There are a few tricks [25]. Some of the less stable

• species can be diluted out and ion pairing can be avoided by using more polar solvents. Nevertheless, the equilibria operating in solution still need to be assessed. Fortunately, the minor ones can often be omitted. Either their inclusion has a negligible impact on the fitting or they contribute less than

Interactions between 4-thiothymidine and water-soluble cyclodextrins: Evidence for supramolecular structures in aqueous solutions

• Vito Rizzi,
• Sergio Matera,
• Paola Semeraro,
• Paola Fini and
• Pinalysa Cosma

Beilstein J. Org. Chem. 2016, 12, 549–563, doi:10.3762/bjoc.12.54

• Since several years the inclusion of organic compounds (guests) within the hydrophobic cavity (host) of cyclodextrins (CDs) has been the subject of many investigations. Interestingly, the formation of inclusion complexes could affect the properties of the guest molecules and, for example, the influence

• complexation mode of the inclusion complexes involving 4-thiothymidine (S4TdR, a known photosensitizer) and five CDs, namely 2-hydroxypropyl-α-cyclodextrin (2-HP-α-CD), 2-hydroxypropyl-β-cyclodextrin (2-HP-β-CD), 2-hydroxypropyl-γ-cyclodextrin (2-HP-γ-CD), heptakis-(2,6-di-O-methyl)-β-cyclodextrin (DIMEB CD

• presence of CDs to prevent its degradation under irradiation. UV–vis, FTIR–ATR and CV measurements suggested the formation of supramolecular structures involving the employed CDs and mainly the pyrimidine ring of S4TdR. 1H NMR analyses confirmed such indication, unveiling the presence of inclusion

New synthetic strategies for xanthene-dye-appended cyclodextrins

• Milo Malanga,
• Andras Darcsi,
• Mihaly Balint,
• Gabor Benkovics,
• Tamas Sohajda and
• Szabolcs Beni

Beilstein J. Org. Chem. 2016, 12, 537–548, doi:10.3762/bjoc.12.53

• spectroscopically inert molecules by guest-induced spectroscopic changes associated with the formation of inclusion complexes. These fluorescent CDs exhibit remarkable molecular recognition abilities, discriminating shape, bulkiness and polarity of the guests [1][2]. Furthermore, CDs can be directly modified with

• to dissociate inclusion complexes (Supporting Information File 1, Figure S7). The presence of two kinds of signals for the methyl units (at 1.06 ppm and 1.14 ppm) in the spectrum recorded in deuterated DMSO confirms the aforementioned observation. The analysis of the DEPT-ed-HSQC spectrum (see

• of the preferred conformation assumed by Rho-β-CD in solution. These data, together with the results presented by Wang et al. [25] about the crystal structure of rhodamine B in lactone form, allowed us to propose the model shown in Figure 6 for the intermolecular inclusion mode of Rho-β-CD. This

Optimized methods for preparation of 6^I-(ω-sulfanyl-alkylene-sulfanyl)-β-cyclodextrin derivatives

• Eva Bednářová,
• Simona Hybelbauerová and
• Jindřich Jindřich

Beilstein J. Org. Chem. 2016, 12, 349–352, doi:10.3762/bjoc.12.38

• ability to form supramolecular inclusion complexes with a wide range of guest molecules [2]. From the native CDs (α-CD, β-CD, and γ-CD containing 6, 7, and 8 glucose units, respectively) the β-CD is studied the most due to its lowest price and the highest guest binding ability. A large number of CD

• inclusion complex with β-CD [22], i.e., a suitable accessibility of the cavity should be kept, and further inclusion complexes could be formed with the guests. Strict inert conditions are also required for the next synthetic step – preparation of compounds 5. The air had to be removed from the reaction