Supramolecular chemistry: from aromatic foldamers to solution-phase supramolecular organic frameworks

• Zhan-Ting Li

Beilstein J. Org. Chem. 2015, 11, 2057–2071, doi:10.3762/bjoc.11.222

• : applications for molecular recognition and self-assembly Donor–acceptor interaction and π-stacking for folding. In January 2001, I returned to SIOC again. When I left SIOC for Urbana in 2000, I had built a small research group with two graduates. Thanks to the persistence of Professor Xi-Kui Jiang [19][20

• be induced by discrete noncovalent forces. In 2014, Jia Tian further extended the concept of solution-phase SOF to 3D space from the self-assembly of tetrahedral 34 and CB[8] [86] (Scheme 18). The 1:2 mixture in water generated a 3D, homogeneous SOF of diamond topology. The pores of the 3D SOF could

Synthesis, antimicrobial and cytotoxicity evaluation of new cholesterol congeners

• Mohamed Ramadan El Sayed Aly,
• Hosam Ali Saad and
• Shams Hashim Abdel-Hafez

Beilstein J. Org. Chem. 2015, 11, 1922–1932, doi:10.3762/bjoc.11.208

• their immunostimulant activities [21]. Finally, the ability of cholesterol derivatives to self-assembly and gelation as supramolecular gels was reviewed [22]. They are beneficially applicable in materials science, reaction media, sensing and responsive materials, energy supply, biomedicine, and tissue

Asymmetric 1,4-bis(ethynyl)bicyclo[2.2.2]octane rotators via monocarbinol functionalization. Ready access to polyrotors

• Cyprien Lemouchi and
• Patrick Batail

Beilstein J. Org. Chem. 2015, 11, 1881–1885, doi:10.3762/bjoc.11.202

• )bicyclo[2.2.2]octane rotators. The good yields allow the large amounts required for self-assembly and subsequent investigations of the dynamics of the rotors in the solid state to be readily prepare. The chemistry, physical chemistry and materials chemistry and physics of asymmetric rotors and their

Star-shaped tetrathiafulvalene oligomers towards the construction of conducting supramolecular assembly

• Masahiko Iyoda and
• Masashi Hasegawa

Beilstein J. Org. Chem. 2015, 11, 1596–1613, doi:10.3762/bjoc.11.175

• , and particles, amphiphilic TTFs having a rigid core and long alkyl chains are one of the best molecular systems. The self-assembly of TTF derivatives in solid and on surface gives rise to a long-distance dynamic ordering as compared with single crystals. Among the recent researches on TTF and its

• conducting liquid. Radially expanded TTF oligomers with a large central π-surface can be expected to show effective intra- and intermolecular delocalization of electrons in the neutral and mixed-valence states. Furthermore, the supramolecular self-assembly of these large molecules having nanophase separation

• derived from the self-assembly of TTF-appended dipeptides were reported [77]. Conductivity measurements performed on the nanofibers of TTF-appended dipeptides indicate a remarkable enhancement in the conductivity after doping with TCNQ (σrt = 1 × 10−5 S cm−1). Conducting nanostructures prepared from

Tetrathiafulvalene-based azine ligands for anion and metal cation coordination

• Awatef Ayadi,
• Aziz El Alamy,
• Olivier Alévêque,
• Magali Allain,
• Nabil Zouari,
• Mohammed Bouachrine and
• Abdelkrim El-Ghayoury

Beilstein J. Org. Chem. 2015, 11, 1379–1391, doi:10.3762/bjoc.11.149

• dinitrophenyl ring coplanar with the hydrazone unit and also by an intramolecular short contact S4···N1 (2.824(6) Å) that makes the TTF unit and the pyridine ring coplanar. In the solid state, the packing arrangement in L1 is characterized by the self-assembly between the TTF donor unit and the dinitrophenyl

Synthesis and evaluation of the biostability and cell compatibility of novel conjugates of nucleobase, peptidic epitope, and saccharide

• Dan Yuan,
• Xuewen Du,
• Junfeng Shi,
• Ning Zhou,
• Abdulgader Ahmed Baoum,
• Khalid Omar Al Footy,
• Khadija Omar Badahdah and
• Bing Xu

Beilstein J. Org. Chem. 2015, 11, 1352–1359, doi:10.3762/bjoc.11.145

• able to act as hydrogelators [4]. Besides the properties of self-assembly, these conjugates are cell compatible [3][4]. Moreover, the NAS conjugates promote the proliferation of mES cells [5] and deliver the oligonucleotide into living cells [6]. Particularly, the incorporation of the functional

• chromatography (HPLC) to purify the target conjugates. Gelation properties Supramolecular hydrogels [18][19][20][21][22][23][24] formed by self-assembly of small molecules in water, as demonstrated previously by us and other researchers, have numerous potential applications, such as encapsulation and delivery of

• conditions used for 5 + 8. These results illustrate that the subtle change in the molecular structures of the conjugates is able to cause drastically different behaviour of self-assembly [37][38]. We also investigated the rheological properties of the three mixtures, 1 + 8, 5 + 8, and 7 + 8 in PBS buffer. As

Synthesis of photoresponsive cholesterol-based azobenzene organogels: dependence on different spacer lengths

• Yuchun Ren,
• Bin Wang and
• Xiuqing Zhang

Beilstein J. Org. Chem. 2015, 11, 1089–1095, doi:10.3762/bjoc.11.122

• ; organogel; photoresponsive; Introduction In the past few decades, low molecular mass organic gelators (LMOGs) have attracted increasing attention not only for basic self-assembly behavior but also for their potential application in areas such as templates [1], light harvesting [2], fluorescent scensing [3

• shifted to 2933 and 2859 cm−1. The above mentioned FTIR spectral changes demonstrated sufficiently that van der Waals interaction between the alkyl chains plays an important role in the self-assembly process of organogels. The XRD studies To reveal the detailed changes in gel molecular of M6, XRD analyses

• another two solvents, corresponding to d values of 5.10 and 3.50 nm, respectively. The different self-assembly modes of gelator in various solvents cause the values changing. The XRD results described above also demonstrated that the molecular interaction and the solvents had a significant impact on the

Glycoluril–tetrathiafulvalene molecular clips: on the influence of electronic and spatial properties for binding neutral accepting guests

• Yoann Cotelle,
• Marie Hardouin-Lerouge,
• Stéphanie Legoupy,
• Olivier Alévêque,
• Eric Levillain and
• Piétrick Hudhomme

Beilstein J. Org. Chem. 2015, 11, 1023–1036, doi:10.3762/bjoc.11.115

• clip with two radical cations stack with and/or without self-assembly affording mixed-valence or π-dimer interactions. At higher potential, the tetracation is provided by another one-electron process on each TTF unit leading to a clip bearing two dications. The graphical representation can be simulated

• ]+ mixed-valence dimer [47][48] and the absorption bands centered around 600 nm to the (TTF˙+)2 π-dimer [49]. The band close to 825 nm could be assigned to cation radicals stack with self-assembly affording mixed-valence. Nevertheless, at this stage, it would be premature to conclude with certainty. The

• bulky groups at the periphery of the TTF moieties does not provide an advantage for the self-assembly of dimers. Moreover, this dimerization phenomenon which is driven by the inclusion of one sidewall into the cavity of the opposing clip is not observed in the solid state for clips 2 and 3 (Figure 8

Tuning the size of a redox-active tetrathiafulvalene-based self-assembled ring

• Sébastien Bivaud,
• Sébastien Goeb,
• Vincent Croué,
• Magali Allain,
• Flavia Pop and
• Marc Sallé

Beilstein J. Org. Chem. 2015, 11, 966–971, doi:10.3762/bjoc.11.108

• allows for modulating the size and the shape of the resulting discrete self-assembly, which therefore incorporate two (M4L2) or three (M6L3) electroactive exTTF sidewalls. Keywords: coordination; metal-driven; redox; self-assembly; tetrathiafulvalene; Findings The coordination-driven approach is a well

• modulating the bulkiness of the ancillary group on the metal complex precursor. The tetrapyridyl-exTTF ligand L1 (Scheme 1, Figure 1a) was synthesized through a palladium catalysed C–H arylation from the naked exTTF [39]. We already reported that the self-assembly process of this tetratopic ligand with cis-M

• acetonitrile containing 0.1 M NBu4PF6 (Figure 5). Compared to ligand L1 which presents the usual electrochemical behavior of exTTF derivatives, i.e. one poorly electrochemically reversible two-electrons oxidation process, the oxidation of exTTF in self-assembly M6L3 is shifted to higher potential (+0.26 V

Is organic chemistry science – and does this question make any sense at all?

• Andreas Kirschning and
• Thomas A. C. Reydon

Beilstein J. Org. Chem. 2015, 11, 893–896, doi:10.3762/bjoc.11.100

• conditions (molecular recognition, self-assembly and dynamic combinatorial chemistry) and how their molecular composition would be; the question why nature developed DNA and RNA that utilize ribose and 2-deoxyribose as central nucleotide building blocks instead of the more abundant and readily available

Impact of multivalent charge presentation on peptide–nanoparticle aggregation

• Daniel Schöne,
• Boris Schade,
• Christoph Böttcher and
• Beate Koksch

Beilstein J. Org. Chem. 2015, 11, 792–803, doi:10.3762/bjoc.11.89

• increasing demand for smaller, more complex, but even cheaper materials, the commonly used “top-down” methods are not available. Thus, new strategies like the “bottom-up” approach have been developed to achieve materials in the nanometer range [11][12]. This technique is based on the self-assembly of small

• switching [15] applications, a variety of specific and site selective binding properties are available [16]. In particular, the specificity of Watson–Crick base pairing of DNA nucleotides can be used for the directed and predictable self-assembly of nanoparticles [17]. The DNA mediated assembly of

Discrete multiporphyrin pseudorotaxane assemblies from di- and tetravalent porphyrin building blocks

• Mirko Lohse,
• Larissa K. S. von Krbek,
• Sebastian Radunz,
• Suresh Moorthy,
• Christoph A. Schalley and
• Stefan Hecht

Beilstein J. Org. Chem. 2015, 11, 748–762, doi:10.3762/bjoc.11.85

• stoichiometry, while the amount of alternative structures can be neglected. Our results illustrate the power of multivalency to program the multicomponent self-assembly of specific entities into discrete functional nanostructures. Keywords: crown ethers; multicomponent assembly; multivalency; porphyrins

• ] to life science [13][14][15][16][17] have benefited from the development of the basic concepts of molecular recognition, templation [18], self-assembly [19], or self-sorting [20][21], just to name a few. More recently, multivalent binding [22][23][24] and cooperativity [25][26] have attracted

• functional building blocks, the formation of specific multiply threaded pseudorotaxanes was achieved, thereby demonstrating the ability to program complex multicomponent self-assembly [74][75]. Results and Discussion Synthesis The synthesis of the two ammonium-substituted porphyrins A2 and A4 was performed

DNA display of glycoconjugates to emulate oligomeric interactions of glycans

• Alexandre Novoa and
• Nicolas Winssinger

Beilstein J. Org. Chem. 2015, 11, 707–719, doi:10.3762/bjoc.11.81

• sugar-core glycoconjugate DNA. Combinatorial self-assembly of PNA glycoconjugates on a DNA microarray. General scheme of the 10,000 member PNA-encoded glycoconjugate library. Oligomeric interaction with arrayed mono- and divalent ligands (represented as the black spheres) as a function of surface

Self-assembly of heteroleptic dinuclear metallosupramolecular kites from multivalent ligands via social self-sorting

• Christian Benkhäuser and
• Arne Lützen

Beilstein J. Org. Chem. 2015, 11, 693–700, doi:10.3762/bjoc.11.79

• central 1,3-diethynylbenzene unit 2 were synthesized. Each of these ligands acts as a multivalent entity for the binding of two copper(I) ions. Upon coordination to the metal ions these two ligands undergo selective self-assembly into heteroleptic dinuclear metallosupramolecular kites in a high-fidelity

• social self-sorting manner as evidenced by NMR spectroscopy and mass spectrometry. Keywords: metal complexes; multivalency; self-assembly; self-sorting; supramolecular chemistry; Tröger's base; Introduction Self-assembly of defined aggregates from multicomponent mixtures through self-sorting effects

• strategy has proven to be very successful for the formation of homoleptic complexes through self-recognition [1][2][3][4]. However, self-assembly processes of metallosupramolecular aggregates that integrate more than one type of bridging ligand and/or one type of metal ion into an assembly are even more

Potential of acylated peptides to target the influenza A virus

• Daniel Lauster,
• Damian Pawolski,
• Julian Storm,
• Kai Ludwig,
• Rudolf Volkmer,
• Henry Memczak,
• Andreas Herrmann and
• Sumati Bhatia

Beilstein J. Org. Chem. 2015, 11, 589–595, doi:10.3762/bjoc.11.65

• has not been explored much in the context of virus inhibition. There are only a few reports on using peptide based self-assembly for influenza virus inhibition [12][13][14]. The entry blocker (EB) which is a peptide fragment derived from the fibroblast growth factor signal sequence 4 (FGF) has a

Properties of cationic monosubstituted tetraalkylammonium cyclodextrin derivatives – their stability, complexation ability in solution or when deposited on solid anionic surface

• Martin Popr,
• Sergey K. Filippov,
• Nikolai Matushkin,
• Juraj Dian and
• Jindřich Jindřich

Beilstein J. Org. Chem. 2015, 11, 192–199, doi:10.3762/bjoc.11.20

• acid [26]. Similar approaches of ionic self-assembly with CDs were used for the preparation of nanoparticles with external CD trigger [27], new material nanostructures [28], polyelectrolyte-surfactant complexes which yield new types of solid mesomorphous materials [29], or membranes with size-selective

• (PErMethylated EthyleneDiAmine substituted). Its binding ability toward selected aromatic guests is compared to the native β-CD at different pH. Deposition of PEMPDA-β-CD on the surface of an anionic Nafion® 117 membrane via ionic self-assembly was also studied along with the determination of sorption kinetics

• SAL and MEQ at acidic and neutral pH, whose stabilities are superior to those of the native β-CD. Immobilization of PEMPDA-β-CD on anionic surface via ionic self-assembly In the next part of our research, we focused on the possibility of deposition of the permanently charged PEMPDA-β-CD onto the solid

Articulated rods – a novel class of molecular rods based on oligospiroketals (OSK)

• Pablo Wessig,
• Roswitha Merkel and
• Peter Müller

Beilstein J. Org. Chem. 2015, 11, 74–84, doi:10.3762/bjoc.11.11

• hydrophobic backbone of the ARs and the markedly smaller surface of the FOL conformation. This behavior resembles folding of peptides and self-assembly of lipids. It is well known that cyclodextrines (CDs), bearing a hydrophobic cavity and a hydrophilic exterior, are able to encapsulate small hydrophobic

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

• kinetics [6]. The hydrophilic nature of the hydrogels is due to the presence of groups along the polymer chains such as hydroxy, carboxy, amide and sulfonic acid [7]. The cross-linking may be either physical or chemical (covalent). According to the reversible and tunable nature of self-assembly, the

• change, making the self-assembly process feasible. In addition, X-ray diffraction showed that some degree of order can be found in the gel structure, attributable to the formation of EO/α-CD complexes that become aggregated into ordered domains. As can be seen in Figure 3, the FTIR spectrum of T25a10

Synthesis and characterization of pH responsive D-glucosamine based molecular gelators

• Navneet Goyal,
• Hari P. R. Mangunuru,
• Bargav Parikh,
• Sonu Shrestha and
• Guijun Wang

Beilstein J. Org. Chem. 2014, 10, 3111–3121, doi:10.3762/bjoc.10.328

• ; naproxen; organogelator; pH responsive; self-assembly; Introduction Low molecular weight gelators (LMWGs) have drawn great attention over the past few decades due to the formation of supramolecular structures and their potential applications as advanced materials [1][2][3][4][5][6][7]. LMWGs are also

Mono- and multilayers of molecular spoked carbazole wheels on graphite

• Stefan-S. Jester,
• A. Vikas Aggarwal,
• Daniel Kalle and
• Sigurd Höger

Beilstein J. Org. Chem. 2014, 10, 2783–2788, doi:10.3762/bjoc.10.295

• the single bonds of two corner units) in the presence of molecular squares [8]. Consequently, an increased understanding of the 2D self-assembly of MSWs on HOPG should nominally pave the way towards a suitable molecular design for (stiffened) hexagons that is compatible with our previous series and

Self-assembled monolayers of shape-persistent macrocycles on graphite: interior design and conformational polymorphism

• Joscha Vollmeyer,
• Friederike Eberhagen,
• Sigurd Höger and
• Stefan-S. Jester

Beilstein J. Org. Chem. 2014, 10, 2774–2782, doi:10.3762/bjoc.10.294

• supramolecular surface patterning is highly oriented pyrolytic graphite (HOPG) which provides large atomically flat terraces between step edges and a sufficient adsorbate mobility, required for the self-assembly process that leads to the 2D crystal formation. For a more detailed understanding of the macrocycle

• unit is varied. The driving forces for their 2D self-assembly are most probably independent from the presence of additional functional groups pointing into the third dimension or located inside the cavity interior. To the best of our knowledge, only little effort has been spent so far on investigating

• the intraannular substitution on the 2D supramolecular self-assembly of macrocycles. Compounds 1–3 (Figure 3) have the same macrocyclic rigid backbone and flexible octadecyloxy periphery and differ only in their intraannular substitution. While 1 has an empty interior, 2 contains an alkyl chain

Removal of volatile organic compounds using amphiphilic cyclodextrin-coated polypropylene

• Ludmilla Lumholdt,
• Sophie Fourmentin,
• Thorbjørn T. Nielsen and
• Kim L. Larsen

Beilstein J. Org. Chem. 2014, 10, 2743–2750, doi:10.3762/bjoc.10.290

• surfaces, including polyethylene, polyvinyl chloride and polyurethane, was previously reported [21]. This method relies on the self-assembly properties of amphiphilic CDs (ACDs), which are CDs with some of the hydroxy groups substituted by alkyl chains. This can be performed in situ by, for example, simply

Linear-g-hyperbranched and cyclodextrin-based amphiphilic block copolymer as a multifunctional nanocarrier

• Yamei Zhao,
• Wei Tian,
• Guang Yang and
• Xiaodong Fan

Beilstein J. Org. Chem. 2014, 10, 2696–2703, doi:10.3762/bjoc.10.284

• ) (PDMAEMA) block (Scheme 1A, P1), allows for the self-assembly and controlled release by taking advantage of the amphiphilic structure and the stimuli-responsive property of PDMAEMA block, respectively. When the hyperbranched polycarbonsilane (HBPCSi) is grafted onto the side chain of PHEMA blocks (Scheme

• in the micellization process. Self-assembly behaviour of P3 in aqueous solution After the synthesis of P3 with amphiphilic characteristics, the corresponding micelle system with a core–shell structure can be formed in aqueous solution by self-assembly. This is driven by the strong hydrophobic

• employed to obtain a deeper insight into the self-assembly morphology and size of P3 in aqueous solution. Figure 1 presents the diameter distributions of P1, P2 and P3 micelles (denoted as MP1, MP2, and MP3) in aqueous solution at 25 ºC. Compared with the Z–average diameter values of P1 (242 nm) and P2

A green approach to the synthesis of novel phytosphingolipidyl β-cyclodextrin designed to interact with membranes

• Yong Miao,
• Florence Djedaïni-Pilard and
• Véronique Bonnet

Beilstein J. Org. Chem. 2014, 10, 2654–2657, doi:10.3762/bjoc.10.278

• order to have good water solubility, selectively modified (methylated) CDs are mostly desired [3]. Among the selectively modified CDs, mono-substituded CD derivatives do not only have self-assembly properties, but also have a good water solubility, allowing passive diffusion across a membrane through

Loose-fit polypseudorotaxanes constructed from γ-CDs and PHEMA-PPG-PEG-PPG-PHEMA

• Tao Kong,
• Lin Ye,
• Ai-ying Zhang and
• Zeng-guo Feng

Beilstein J. Org. Chem. 2014, 10, 2461–2469, doi:10.3762/bjoc.10.257

• ) initiated by 2-bromoisobutyryl end-capped PPO-PEO-PPO as a macroinitiator in DMF. Attaching PHEMA blocks altered the self-assembly process of the pentablock copolymer with γ-CDs in aqueous solution. Before attaching the PHEMA, the macroinitiator was preferentially bent to pass through the inner cavity of γ

• instead of PEG, and γ-CDs accommodate either single-chain PPG or double-chain PEG [1]. The driving force behind the self-assembly is mostly ascribed to a suitable fit between the cross-sectional area of the incoming polymer chain and the cavity size of the CDs [2]. However, the cavity shape and size of

• with γ-CDs in aqueous solution to form PPRs. The results of 1H NMR, WXRD, DSC, TGA, 13C CP/MAS NMR and FTIR analyses indicate that the attachment of PHEMA clearly changes the self-assembly direction of γ-CDs with PHEMA-PPO-PEO-PPO-PHEMA. This results in unique, single-chain stranded, loose-fit PPRs