Synthesis of a water-soluble 2,2′-biphen[4]arene and its efficient complexation and sensitive fluorescence enhancement towards palmatine and berberine

• Xiayang Huang,
• Xinghua Zhang,
• Tianxin Qian,
• Junwei Ma,
• Lei Cui and
• Chunju Li

Beilstein J. Org. Chem. 2018, 14, 2236–2241, doi:10.3762/bjoc.14.198

• as bioimaging and self-assembled drug delivery systems [33][34][35][36][37][38][39][40]. For example, our group demonstrated a direct host–guest complexation-based drug delivery system for oxaliplatin by carboxylatopillar[6]arene [36]. The encapsulation could not only improve the drug‘s stability in

• by the present encapsulation-induced fluorescence enhancement. Results and Discussion Synthesis Scheme 1 shows the synthetic route of 2,2’-CBP4 [51], which is very similar with the procedure of water-soluble 4,4’-biphenarene [46]. Perhydroxylated 2,2’-biphen[4]arene, (2,2’-OHBP4) with hydroxy

• changes were observed for the host–guest mixture of P and 2,2’-CBP4 (Supporting Information File 1, Figure S9), suggesting a similar binding mode of an inclusion complex. The host–guest encapsulation was then confirmed by 2D NOESY experiments, as shown in Figures S10 and S11, Supporting Information File 1

Rational design of boron-dipyrromethene (BODIPY) reporter dyes for cucurbit[7]uril

• Mohammad A. Alnajjar,
• Jürgen Bartelmeß,
• Robert Hein,
• Pichandi Ashokkumar,
• Mohamed Nilam,
• Werner M. Nau,
• Knut Rurack and
• Andreas Hennig

Beilstein J. Org. Chem. 2018, 14, 1961–1971, doi:10.3762/bjoc.14.171

• motifs for CB7. The unprotonated dyes show low fluorescence due to photoinduced electron transfer (PET), whereas the protonated dyes are highly fluorescent. Encapsulation of the binding motif inside CB7 positions the aniline nitrogen at the carbonyl rim of CB7, which affects the pKa value, and leads to a

• encapsulation of the anchor group by CB7 has no effect on the spectroscopic properties of the dyes. At intermediate pH, the protonated fraction of the dye will be strongly bound by CB7, which affects the protonation equilibrium of the dye and leads to more protonated dye being produced. The net outcome is an

An amphiphilic pseudo[1]catenane: neutral guest-induced clouding point change

• Tomoki Ogoshi,
• Tomohiro Akutsu and
• Tada-aki Yamagishi

Beilstein J. Org. Chem. 2018, 14, 1937–1943, doi:10.3762/bjoc.14.167

• temperature, but de-solvation occurs upon heating, which triggers aggregation of the hydrophobic pillar[n]arene cores. The amphiphilic pillar[n]arenes can capture guest molecules with encapsulation of an ionic guest molecule resulting in a change of the hydrophobic/hydrophilic ratio, and consequently a change

• complex system between amphiphilic pillar[6]arene 2 and a photoresponsive cationic azobenzene guest [6]. However, neutral guest molecules could not induce a clear LCST change because encapsulation of the neutral guest in the hydrophobic pillar[n]arene core did not significantly change the hydrophobic

Host–guest complexes of conformationally flexible C-hexyl-2-bromoresorcinarene and aromatic N-oxides: solid-state, solution and computational studies

• Rakesh Puttreddy,
• Ngong Kodiah Beyeh,
• S. Maryamdokht Taimoory,
• Daniel Meister,
• John F. Trant and
• Kari Rissanen

Beilstein J. Org. Chem. 2018, 14, 1723–1733, doi:10.3762/bjoc.14.146

• encapsulation in the bowl-shaped upper rim (endo complexation) due to size complementarity between host cavity and guest shape, and are generally stabilised through multiple C–H···π interactions [26][27][28]. The cavity capacity to undergo induced conformational changes in response to the incorporation of

• host’s hydroxy groups. To our surprise, our previous X-ray crystal structures of 3@BrC3 and 3@BrC2 complexes obtained from acetone showed interactions with the putative guests (i.e., N-oxide and acetone molecules) by encapsulation within the upper-rim and lower-rim cavity [39][40]. Therefore, in an

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

• ) observed also by 1H NMR [26] are retained during the whole 12 ns simulation (Figure 5b). The binding affinity of the CHL/β-CD complexes in aqueous solution has been previously calculated for different orientations of CHL in β-CD monomers as well as CHL encapsulation in head–head, head–tail and tail–tail

• . Moreover, the high binding affinity values ΔG, estimated at 300 K and 340 K (−19.5 and −19.3 kcal/mol, respectively), indicate that the encapsulation of cholesterol in β-CD head–head dimer vastly increases the affinity of the CHL/β-CD inclusion complex compared to models of 1:1 host/guest stoichiometry

Nanoreactors for green catalysis

• M. Teresa De Martino,
• Loai K. E. A. Abdelmohsen,
• Floris P. J. T. Rutjes and
• Jan C. M. van Hest

Beilstein J. Org. Chem. 2018, 14, 716–733, doi:10.3762/bjoc.14.61

• reactions [95][97]. The first successful attempt was reported by Chung and Rhee, in which they showed the encapsulation of a bimetallic Pt–Pd catalyst in a highly branched PMAM-OH dendrimer corona [93]. These catalytic dendrimers were employed in partial hydrogenation of 1,3-cyclooctadiene into cyclooctene

Exploring mechanochemistry to turn organic bio-relevant molecules into metal-organic frameworks: a short review

• Vânia André,
• Sílvia Quaresma,
• João Luís Ferreira da Silva and
• M. Teresa Duarte

Beilstein J. Org. Chem. 2017, 13, 2416–2427, doi:10.3762/bjoc.13.239

• liquid led to the formation of a 1D coordination polymer monohydrate, a tetrahydrate complex and an octahydrate, respectively (Figure 2) [7][29]. BioMOFs based on generally regarded as safe (GRAS), bioactive or endogenous linkers for the encapsulation of APIs Another approach to build a BioMOF consists

• of the use of generally regarded as safe (GRAS), bioactive or endogenous linkers to form the 3D framework followed by the encapsulation of the APIs in the BioMOF. In these cases, the 3D frameworks may be synthesized by mechanochemistry, but the encapsulation of the drug is usually carried out by

• promising candidate to biomedical applications [8]. Indeed, ZIF-8 has been largely used to encapsulate APIs such as doxorubicin, an anticancer drug [96][142] or even as an efficient pH-sensitive drug-delivery system [92][95][143][144]. Usually, the encapsulation of small molecules into MOFs involves two

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

• compound is evaluated by the DPPH assay. Keywords: antioxidant activity; co-lyophilization; fisetin; gamma-cyclodextrin; molecular encapsulation; solid-state analysis; Introduction Flavonoids, natural compounds with numerous beneficial actions on human health, including antioxidant [1], anti-inflammatory

• resulting in a low oral bioavailability. This limitation can be overcome by using micro or nano-encapsulation methods that allow preparing fisetin oral liquid formulations that are well absorbed. Previously reported encapsulation strategies include liposomes [18], nanoemulsions [19], nanocochleates (which

• product improves its stability and makes it easier to handle, transport and store. Furthermore, the used encapsulation method applied only edible ingredients: γ-CD, water, and ethanol, being thus suitable for future applications in food fortification. A detailed physicochemical analysis of the product

Chemical systems, chemical contiguity and the emergence of life

• Terrence P. Kee and
• Pierre-Alain Monnard

Beilstein J. Org. Chem. 2017, 13, 1551–1563, doi:10.3762/bjoc.13.155

• /association with the chemical system structure or to the encapsulation of a reaction “machinery” within it. Interface-linked catalysis: The oligomerization of peptides from amino acids with condensing agents has been demonstrated to occur in the presence of phospholipid vesicles [65][66][67]. In these studies

• interconnectedness in the systems is visible if one considers the various arrows between molecules/components: The catalytic machinery is defined and controlled by the information component (I) and the compartment (via encapsulation), whose molecular species are in turn produced by the catalytic machinery (II

• chemicals of the protocell are highlighted by thick grey dotted frames. Products of the catalytic machinery are placed over a grey background. The involvement of catalysts is depicted by dashed arrows, that of information components with a plain arrow, and that of the compartment (expect the encapsulation

Framing major prebiotic transitions as stages of protocell development: three challenges for origins-of-life research

• Ben Shirt-Ediss,
• Sara Murillo-Sánchez and
• Kepa Ruiz-Mirazo

Beilstein J. Org. Chem. 2017, 13, 1388–1395, doi:10.3762/bjoc.13.135

• classical coacervates of Oparin’s [17] and more recent versions of it [18], to the obcell theory of Cavalier Smith’s [19], based on Blobel’s ideas [20], later also revisited by Griffiths [21]. These proposals do not especially favour vesicle compartments, because the encapsulation of the incipient

• will defend the view that in order to reconstruct this process a strict ‘bottom-up’ approach should be pursued, starting with chemical precursors of biomolecules, rather than with fully functional biomolecules. Whereas the encapsulation of biopolymers (DNA, RNA, proteins) or cell extracts in self

• longer we postpone the appearance of chemical encapsulated systems, the more intractable the problem of compartmentalization will surely become. Indeed, if reaction networks could develop their catalytic efficiency in compartment-free scenarios, their eventual encapsulation within lipid vesicles would

BODIPY-based fluorescent liposomes with sesquiterpene lactone trilobolide

• Ludmila Škorpilová,
• Silvie Rimpelová,
• Michal Jurášek,
• Miloš Buděšínský,
• Jana Lokajová,
• Roman Effenberg,
• Petr Slepička,
• Tomáš Ruml,
• Eva Kmoníčková,
• Pavel B. Drašar and
• Zdeněk Wimmer

Beilstein J. Org. Chem. 2017, 13, 1316–1324, doi:10.3762/bjoc.13.128

• encapsulation of construct 6 into the liposomes improved the drug distribution in cancer cells and was followed by cell death. This new liposomal trilobolide derivative not only retains the biological properties of pure trilobolide, but also enhances the bioavailability, and thus has potential for the use in

• production in the presence of LPS; at 100 µM concentration of construct 6, the level of NO raised up to 30 µM. In further biological evaluation, we found that construct 6 was efficiently localized inside human U-2 OS and HeLa cancer cells. The encapsulation of construct 6 into liposomes resulted in

The effect of cyclodextrin complexation on the solubility and photostability of nerolidol as pure compound and as main constituent of cabreuva essential oil

• Joyce Azzi,
• Pierre-Edouard Danjou,
• David Landy,
• Steven Ruellan,
• Lizette Auezova,
• Hélène Greige-Gerges and
• Sophie Fourmentin

Beilstein J. Org. Chem. 2017, 13, 835–844, doi:10.3762/bjoc.13.84

• susceptibility to degradation limit its application. The aim of our study was to improve the solubility and photostability of Ner through its encapsulation in different cyclodextrins (CDs). The formation constants of cis-, trans-Ner and their commercial mixture with various CDs (α-CD, β-CD, γ-CD, HP-β-CD, RAMEB

• , CRYSMEB and SBE-β-CD) were determined by phase solubility studies and confirmed by the spectral displacement UV-visible method. The solubility of cabreuva essential oil (EO) rich in trans-Ner was also evaluated by total organic carbon (TOC) analysis. The encapsulation efficiency (EE %) of Ner in HP-β-CD

• solid complexes was assessed by HPLC. The structural characterization of CD/trans-Ner inclusion complex was then conducted by NMR spectroscopy followed by molecular modelling studies. The effect of encapsulation on the Ner photostability was also carried out over time under UVB irradiation. AL-type

How and why kinetics, thermodynamics, and chemistry induce the logic of biological evolution

• Addy Pross and
• Robert Pascal

Beilstein J. Org. Chem. 2017, 13, 665–674, doi:10.3762/bjoc.13.66

• direct binding or encapsulation, but that functional linkages in which reactants or products could be common to different systems would have been important as well. Organic chemistry and the origin of life The lines of thought developed here point towards a global approach to account for the emergence of

Novel β-cyclodextrin–eosin conjugates

• Gábor Benkovics,
• Damien Afonso,
• András Darcsi,
• Szabolcs Béni,
• Sabrina Conoci,
• Éva Fenyvesi,
• Lajos Szente,
• Milo Malanga and
• Salvatore Sortino

Beilstein J. Org. Chem. 2017, 13, 543–551, doi:10.3762/bjoc.13.52

• ), to increase the aqueous solubility and to prevent the undesired aggregation of the PS inside the cell. Another advantage offered by the covalently connected CD–PS systems is the encapsulation of hydrophobic photoactivatable drug molecules in the CD cavity, enabling thereby the application of these

Interactions between photoacidic 3-hydroxynaphtho[1,2-b]quinolizinium and cucurbit[7]uril: Influence on acidity in the ground and excited state

• Jonas Becher,
• Daria V. Berdnikova,
• Darinka Dzubiel,
• Heiko Ihmels and
• Phil M. Pithan

Beilstein J. Org. Chem. 2017, 13, 203–212, doi:10.3762/bjoc.13.23

• effect of the ligand–CB[n] interplay may be used to modify and control the photochemical properties of a guest molecule [8][9]. For instance, the encapsulation of photoactive molecules in the constrained medium of a cucurbituril cavity enables the performance of chemo-, regio- or stereoselective

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

• on passing from the empty CDNS to the drug-loaded CDNS, thus showing that the drug encapsulation can be seen as the formation of a real supramolecular aggregate rather than a conglomerate of two solid components. Finally, the structural features obtained from the different solid-state NMR approaches

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

• , the structural elucidation of the three natural CDs, α-, β-, and γ-CDs composed of 6-, 7-, and 8-membered α-D-glucopyranoses linked by α-1,4 glycosidic bonds, allowed the development and the rational study of their encapsulation properties [6][7]. As their water solubility differs significantly, a

• NMR signals corresponding to Trp residues were shifted upon the addition of G1-β-CD due to encapsulation of the tryptophan residues in the G1-β-CD cavity [92]. In addition, the 1H NMR signals for cysteine 64 and isoleucine 98 were also influenced to a considerable extent with the addition of G1-β-CD

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

• gave polymers with higher molecular weights and wider distributions (Table 1, entries 1 and 4). In order to investigate the effect of encapsulation of monomer by α-CD moiety, the reactions in the presence of 1,6-hexanediol (C6 diol) as a competitive guest molecule were also investigated. C6 diol was

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

• cross-linked cyclodextrin-based polymer for the removal of metals and organic pollutants present in polycontaminated effluents. Cyclodextrins (CDs), synthetic substances obtained from the enzymatic degradation of starch, belong to the family of cage molecules. They present remarkable encapsulation

Synthesis and characterization of benzodithiophene and benzotriazole-based polymers for photovoltaic applications

• Desta Gedefaw,
• Marta Tessarolo,
• Margherita Bolognesi,
• Mario Prosa,
• Renee Kroon,
• Wenliu Zhuang,
• Patrik Henriksson,
• Kim Bini,
• Ergang Wang,
• Michele Muccini,
• Mirko Seri and
• Mats R. Andersson

Beilstein J. Org. Chem. 2016, 12, 1629–1637, doi:10.3762/bjoc.12.160

• of the solar cell was exactly 6 mm2. During testing, each cell was carefully masked, by calibrated mask, to prevent an excess photocurrent generated from the parasitic device regions outside the overlapped electrodes area. All solar cells were tested, without encapsulation, inside the glove box in

Synthesis of a deuterated probe for the confocal Raman microscopy imaging of squalenoyl nanomedicines

• Eric Buchy,
• Branko Vukosavljevic,
• Maike Windbergs,
• Dunja Sobot,
• Camille Dejean,
• Simona Mura,
• Patrick Couvreur and
• Didier Desmaële

Beilstein J. Org. Chem. 2016, 12, 1127–1135, doi:10.3762/bjoc.12.109

• , the use of fluorescent probes requires the covalent binding of large dye molecules (bodipy, cyanine, rhodamine etc, ...) to the drug conjugate, thus potentially modifying its physicochemical profile as well as the in vivo fate and the pharmacological activity. A simple encapsulation of an amphiphilic

Stimuli-responsive HBPS-g-PDMAEMA and its application as nanocarrier in loading hydrophobic molecules

• Yongsheng Chen,
• Li Wang,
• Haojie Yu,
• Zain-Ul-Abdin,
• Ruoli Sun,
• Guanghui Jing,
• Rongbai Tong and
• Zheng Deng

Beilstein J. Org. Chem. 2016, 12, 939–949, doi:10.3762/bjoc.12.92

• applications under different conditions. The study of the encapsulation of hydrophobic molecules into amphiphilic nanocarriers is important for cancer or tumor therapies because many of the newly synthesized efficient and useful drugs are insoluble in water. Hyperbranched or star-like polymers have become

• distribution which means that these stimuli-responsive polymers may be suitable for medicinal use. The encapsulation of hydrophobic molecules in HBPS-g-PDMAEMA aggregates To confirm the loading capability of HBPS-g-PDMAEMA aggregates for hydrophobic molecules, pyrene was used as a model molecule. Pyrene, a

• preparation of HBPS-g-PDMAEMA/NR solutions was similar to HBPS-g-PDMAEMA/pyrene solutions. As shown in Figure 8A, the encapsulation of NR by HBPE-g-PDMAEMA aggregates can be observed by the naked eye. The solution containing these aggregates showed the pink color of NR in hydrophobic environment, and

From steroids to aqueous supramolecular chemistry: an autobiographical career review

• Bruce C. Gibb

Beilstein J. Org. Chem. 2016, 12, 684–701, doi:10.3762/bjoc.12.69

• exceedingly stable capsular complexes (Figure 6). Regarding their stability, even at 5 μM, NMR showed complete encapsulation of estradiol; giving a minimum apparent binding constant for the empty capsule (the host is actually monomeric in the absence of guests) of 1 × 108 M−1. When the steroid was very large

• way up to C50H102. In considering this we have found that for the octa-acid dimer the boundary between two or one guest encapsulation is C8H18 [47], but that guests longer than C12H26 must compress in some manner in order to be accommodated. There are three principle ways that such large guests

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

• Figure S1A (Supporting Information File 1) is related to changes in the polarity due to the inclusion of the S4TdR into the cavity of the CDs [59]. The results, related to the encapsulation of CH3 group, were emphasized considering the observation reported in [56]: when aliphatic protons enter the

Enabling technologies and green processes in cyclodextrin chemistry

• Giancarlo Cravotto,
• Marina Caporaso,
• Laszlo Jicsinszky and
• Katia Martina

Beilstein J. Org. Chem. 2016, 12, 278–294, doi:10.3762/bjoc.12.30

• and a high electrochemical response [74]. CuAAC has been successfully used to immobilize molecules on polymers and biopolymers as well as to join sugars to peptides and proteins. CD-polyglycerol dendron amphiphiles (CD-PG) have also been obtained. This derivative showed high encapsulation efficiency