Peptide–polymer ligands for a tandem WW-domain, an adaptive multivalent protein–protein interaction: lessons on the thermodynamic fitness of flexible ligands

• Katharina Koschek,
• Vedat Durmaz,
• Oxana Krylova,
• Marek Wieczorek,
• Shilpi Gupta,
• Martin Richter,
• Alexander Bujotzek,
• Christina Fischer,
• Rainer Haag,
• Christian Freund,
• Marcus Weber and
• Jörg Rademann

Beilstein J. Org. Chem. 2015, 11, 837–847, doi:10.3762/bjoc.11.93

• interfere with FBP21-dependent splicing events. Several multivalent ligands were synthesized on the basis of various polymer supports differing in their chemical structure, backbone flexibility, morphology, and ligand loading. The obtained materials were then investigated in order to contribute to the

• residues. Selection of polymer carriers and synthesis of multivalent ligands Three biocompatible polymers with different chemical structure, backbone flexibility and polymer morphology were selected as multivalent ligand carriers, two linear polymers and one dendritic polymer (Scheme 1). Linear poly(N-(2

• other than in pHPMA (3.4) and hPG (3.7 nm). The larger distance in hPG might be related to the hypervalent morphology of this carrier, which possibly limits the proximity of attached ligands. Expected values of averaged (over time and atoms) radial distributions (correlating with normalized mean

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

• nanoparticles. As the assembly of charged gold nanoparticles depends on the local charge of the coiled-coil in a multivalent fashion, we wanted to study different aspects of nanoparticle–peptide interactions such as the aggregation tendency of the peptide and the morphology of the obtained peptide–nanoparticle

• produces coiled-coil monomers. This effect was observed in all cases (Figure 2D). To resolve the morphology of the quaternary structures, TEM and/or Cryo TEM were applied to all peptides at pH 9 except for VW05; a representative image for R2A2 is shown in Figure 3. Negative staining TEM of 100 µM R2A2 at

• energy. Nevertheless, all peptide–nanoparticle interactions are entropically favored processes as entropy increases with along with binding energy. Morphological studies of peptide-induced nanoparticle assemblies Cryo TEM was used to gain insight into the morphology of the peptide–nanoparticle aggregates

Regulation of integrin and growth factor signaling in biomaterials for osteodifferentiation

• Qiang Wei,
• Theresa L. M. Pohl,
• Anja Seckinger,
• Joachim P. Spatz and
• Elisabetta A. Cavalcanti-Adam

Beilstein J. Org. Chem. 2015, 11, 773–783, doi:10.3762/bjoc.11.87

• mechanical unit rather than biochemical unit in the theory of mechanotransduction. In this theory, integrin–ligand interactions cause cytoskeleton reorganization, which further affects the nuclear morphology, since the nucleus connects to the other side of the cytoskeleton. The change of the nuclear

• morphology subsequently propagates to the interphase chromosomes which are linked to the nuclear lamins at matrix-attachment regions [44]. Therefore, the genome and gene expression may be influenced. Based on this theory, the MSC differentiation can be modulated by the lamin-A level. Low lamin-A levels

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

• other amphiphilic peptides used here. Notably, such larger structures are consistent with the observation of Matsubara et al. at least with respect to the dimension. Although the authors did not visualize the morphology of their structures, the DLS data of this report indicate different sized assembly

IR and electrochemical synthesis and characterization of thin films of PEDOT grown on platinum single crystal electrodes in [EMMIM]Tf₂N ionic liquid

• Andrea P. Sandoval,
• Marco F. Suárez-Herrera and
• Juan M. Feliu

Beilstein J. Org. Chem. 2015, 11, 348–357, doi:10.3762/bjoc.11.40

• ) < Pt(110) < Pt(111) [6]. The synthesis of other conducting polymers on well-defined surfaces [7][8][9][10] and templates [11] also has shown how the surface affects their adhesion, coverage, morphology and redox kinetics. On the other hand, the synthesis of conducting polymers in ionic liquids (ILs

• redox processes of PEDOT films is faster in [EMMIM]Tf2N than in acetonitrile [6], which is a relevant characteristic feature for the use of PEDOT thin films to build electrochromic devices or actuators [12][26][27]. Morphology by AFM Figure 5 shows the AFM images of the polymer synthesized with a charge

• , anhydrous, 99.8%) A commercially available potentiostat/galvanostat µ Autolab III (Ecochemie) was used for the electrochemical experiments. The morphology of the polymer was studied with a NanoScope III Multimed contact AFM. Scan rate of 2 Hz. A standard cantilever of Si3N4 with piramidal tips (Digital

C-5’-Triazolyl-2’-oxa-3’-aza-4’a-carbanucleosides: Synthesis and biological evaluation

• Roberto Romeo,
• Caterina Carnovale,
• Salvatore V. Giofrè,
• Maria A. Chiacchio,
• Adriana Garozzo,
• Emanuele Amata,
• Giovanni Romeo and
• Ugo Chiacchio

Beilstein J. Org. Chem. 2015, 11, 328–334, doi:10.3762/bjoc.11.38

• maintenance medium (DMEM with 2% heat inactivated FCS) was used to culture the viruses. Cell viability. The cytotoxicity of the tested compounds was evaluated by measuring the effect created on cell morphology and/or cell growth (cytostatic activity). Cell monolayers were prepared in 24-well tissue culture

• microscopically detectable variation of cell morphology. The extent of cytostatic activity was measured as inhibition of cell growth using the MTT method, as previously described [49][50]. The 50% cytotoxic dose (CC50) is the compound concentration required to reduce cell proliferation by 50% relative to the

Natural phenolic metabolites with anti-angiogenic properties – a review from the chemical point of view

• Qiu Sun,
• Jörg Heilmann and
• Burkhard König

Beilstein J. Org. Chem. 2015, 11, 249–264, doi:10.3762/bjoc.11.28

• metastases. Nevertheless, the morphology and pathophysiology of these blood vessels differs significantly from physiological ones as they are less effective and show a lower state of organization and control [3]. Since the discovery of the mechanism of angiogenesis and its crucial role in tumor development

Formulation development, stability and anticancer efficacy of core-shell cyclodextrin nanocapsules for oral chemotherapy with camptothecin

• Hale Ünal,
• Naile Öztürk and
• Erem Bilensoy

Beilstein J. Org. Chem. 2015, 11, 204–212, doi:10.3762/bjoc.11.22

• , 0.1% w/v polymer, 1% v/v oil and 1:2 organic to aqueous phase volume ratios were selected as parameters for the CPT-loaded nanocapsule preparation. CPT-loaded CD nanocapsules were characterized in terms of mean particle size and size distribution, surface charge and morphology (see Supporting

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

• about 500 Pa. The gel formed by amide 11 had smaller G' and G'' values. These results indicate that all the gels are stable and have elastic properties. The gels formed by urea derivatives are more stable than the amide gels. The morphology of the amide and urea gels was also studied by optical

Thermal and oxidative stability of the Ocimum basilicum L. essential oil/β-cyclodextrin supramolecular system

• Daniel I. Hădărugă,
• Nicoleta G. Hădărugă,
• Corina I. Costescu,
• Ioan David and
• Alexandra T. Gruia

Beilstein J. Org. Chem. 2014, 10, 2809–2820, doi:10.3762/bjoc.10.298

• complexation process, was 74.2%. This relatively high recovery yield for the β-CD complex can be explained by the lower water (as well as ethanol/water) solubility. The quality of the essential oil/β-CD complex formation was sustained by the morphology of the complex crystals, evaluated by scanning electron

Detonation nanodiamonds biofunctionalization and immobilization to titanium alloy surfaces as first steps towards medical application

• Juliana P. L. Gonçalves,
• Afnan Q. Shaikh,
• Manuela Reitzig,
• Daria A. Kovalenko,
• Jan Michael,
• René Beutner,
• Gianaurelio Cuniberti,
• Dieter Scharnweber and
• Jörg Opitz

Beilstein J. Org. Chem. 2014, 10, 2765–2773, doi:10.3762/bjoc.10.293

• -PEA. Immobilization of DND Scanning electron microscopy (SEM) was used to characterize the surface morphology of titanium samples coated with previously functionalized nanodiamonds. DND before and after functionalization were used to evaluate the improvement on the interaction of DND with the titanium

Anomalous diffusion of Ibuprofen in cyclodextrin nanosponge hydrogels: an HRMAS NMR study

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

Beilstein J. Org. Chem. 2014, 10, 2715–2723, doi:10.3762/bjoc.10.286

• )2 to achieve sufficient contrast. The picture clearly illustrates the porous morphology of the material and the structural heterogeneities in the pore size distribution. Confinement effects are expected to drive the diffusion process from normal to subdiffusive behaviour and interaction with the

• structure of the CDNSEDTA 1:8 is expected to show a high degree of heterogeneity in the distribution of pores, due to rearrangements caused by the steric hindrance. The TEM image of Figure 4b shows the details of the pores heterogeneity and the sponge-like morphology. The slightly superdiffusive behaviour

Synthesis and properties of novel star-shaped oligofluorene conjugated systems with BODIPY cores

• Clara Orofino-Pena,
• Diego Cortizo-Lacalle,
• Joseph Cameron,
• Muhammad T. Sajjad,
• Pavlos P. Manousiadis,
• Neil J. Findlay,
• Alexander L. Kanibolotsky,
• Dimali Amarasinghe,
• Peter J. Skabara,
• Tell Tuttle,
• Graham A. Turnbull and
• Ifor D. W. Samuel

Beilstein J. Org. Chem. 2014, 10, 2704–2714, doi:10.3762/bjoc.10.285

• structures [17]. A multidimensional molecular architecture provides excellent film-forming properties of the materials and an isotropic morphology of the final film. In the case of oligofluorenes with benzene [18] and truxene cores [19][20][21][22], this design methodology has yielded promising materials for

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

• 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

Solution processable diketopyrrolopyrrole (DPP) cored small molecules with BODIPY end groups as novel donors for organic solar cells

• Diego Cortizo-Lacalle,
• Calvyn T. Howells,
• Upendra K. Pandey,
• Joseph Cameron,
• Neil J. Findlay,
• Anto Regis Inigo,
• Tell Tuttle,
• Peter J. Skabara and
• Ifor D. W. Samuel

Beilstein J. Org. Chem. 2014, 10, 2683–2695, doi:10.3762/bjoc.10.283

• pair or exciton into free charge and their transport to the electrodes are critical for device operation. Dissociation and transport are two processes that are strongly linked with the morphology of the active layer. Therefore, controlling the morphology can lead to improved device performance. A

• common technique to optimise morphology is to vary the donor/acceptor ratio. A screening of various donor/acceptor ratios revealed that the most promising performance was evident with the ratio 1:3 (Figures S15 and S16, Supporting Information File 1). As the concentration of the acceptor is increased

• propensity to aggregate. As such, an investigation into the morphology of the optimised blends was carried out. Wide-field images indicate more aggregates in the blend 10:PC71BM (1:3) compared to that in 9:PC71BM (1:3). These aggregates are contained within red circles (Figures S9 and S10, Supporting

Encapsulation of biocides by cyclodextrins: toward synergistic effects against pathogens

• Véronique Nardello-Rataj and
• Loïc Leclercq

Beilstein J. Org. Chem. 2014, 10, 2603–2622, doi:10.3762/bjoc.10.273

• of the complexes by observing the morphology of E. coli. When butylparaben or triclosan were used as biocidal agent in the presence of CP-β-CD, the cell membrane was not affected by the complex suggesting that the biocide/CP-β-CD complexes inhibit only the metabolism. Indeed, triclosan exhibits its

• nitrate solution with glucose as a reducing agent, sodium hydroxide as a reaction catalyst and β-CD as a stabilizer [90]. They also investigated the structure and morphology of the stabilizing layer around the silver nanoparticles. The modification of the surface of the nanoparticles by β-CD thus

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

• PEP26M27CD. Noteworthy is the fact that the –CH3 resonance of PEP26M27CD similarly displays weak peak splits. This implies that the PHEMA and PPO blocks probably adopt unusual substructure conformations in the cavity of γ-CDs, different from the general morphology in the original PEP26M. As a result, they

Molecular ordering at electrified interfaces: Template and potential effects

• Thanh Hai Phan and
• Klaus Wandelt

Beilstein J. Org. Chem. 2014, 10, 2243–2254, doi:10.3762/bjoc.10.233

• the potential regime above the first reduction peak P1 in Figure 1, results in the instantaneous formation of a highly ordered DBV2+ film. Figure 4 shows representative STM images describing the surface morphology and molecular structure of the DBV2+adlayer. First, the straight step-edges in Figure 4a

• running by each other at a typical angle of 120° still remain, providing a first indication of the persistence of the c(p × √3)Cl layer underneath the organic molecules (see also Figure 6). This indicates that the DBV2+ adlayer has no significant impact on the substrate-surface morphology, which is

• structure: 14.4 nm × 14.4 nm, 5.58 nm × 5.58 nm, It = 2.0 nA, Ub = 75 mV, E = 0.0 mV; c) Hard-sphere model of the chloride-modified Cu(111) surface. Typical STM images of the surface morphology and high-resolution images of the DBV2+ related herring-bone phase on Cl/Cu(111): a) Surface morphology of the

Expanding the scope of cyclopropene reporters for the detection of metabolically engineered glycoproteins by Diels–Alder reactions

• Anne-Katrin Späte,
• Verena F. Schart,
• Julia Häfner,
• Andrea Niederwieser,
• Thomas U. Mayer and
• Valentin Wittmann

Beilstein J. Org. Chem. 2014, 10, 2235–2242, doi:10.3762/bjoc.10.232

• additional experiments see Figure S1, Supporting Information File 1). Brightfield images were recorded to check the cell morphology. These experiments show that all three cyclopropene derivatives 1, 2, and 3 are accepted by the cell’s biosynthetic machinery. However, membrane staining resulting from

Synthesis and optical properties of pyrrolidinyl peptide nucleic acid carrying a clicked Nile red label

• Nattawut Yotapan,
• Chayan Charoenpakdee,
• Pawinee Wathanathavorn,
• Boonsong Ditmangklo,
• Hans-Achim Wagenknecht and
• Tirayut Vilaivan

Beilstein J. Org. Chem. 2014, 10, 2166–2174, doi:10.3762/bjoc.10.224

• fashion. PNA–DNA duplexes have different structural morphology and electrostatic potential surfaces from DNA–DNA duplexes and therefore they are interacting differently with DNA-binding dyes [23][24][25]. We had recently introduced a new conformationally constrained pyrrolidinyl PNA known as acpcPNA that

The effect of permodified cyclodextrins encapsulation on the photophysical properties of a polyfluorene with randomly distributed electron-donor and rotaxane electron-acceptor units

• Aurica Farcas,
• Ana-Maria Resmerita,
• Pierre-Henri Aubert,
• Flavian Farcas,
• Iuliana Stoica and
• Anton Airinei

Beilstein J. Org. Chem. 2014, 10, 2145–2156, doi:10.3762/bjoc.10.222

• granular morphology with a lower dispersity supported by a smaller roughness exponent compared with the non-rotaxane counterpart. Keywords: cyclodextrins; energy band gaps; fluorescence lifetimes; persilylated cyclodextrins; supramolecular encapsulation; surface morphology; Introduction Semiconducting π

• have been widely employed to investigate the solid state redox behavior of some hole-transporting layers [41], semiconducting polymer layers [13][29][30][42], or electrodeposited layers [43]. In order to remove any precedent electrochemical processes, which could change the film morphology by the

• large scan length, each curve turns into a plateau. The non-rotaxane 4 film surface displays granular morphology with grain diameters of 99 ± 17 nm. The dispersity of grain sizes was supported by a higher roughness exponent of 0.303 (Figure 11). 4a and 4b polyrotaxanes also show a granular morphology

Scalable synthesis of 5,11-diethynylated indeno[1,2-b]fluorene-6,12-diones and exploration of their solid state packing

• Bradley D. Rose,
• Peter J. Santa Maria,
• Aaron G. Fix,
• Chris L. Vonnegut,
• Lev N. Zakharov,
• Sean R. Parkin and
• Michael M. Haley

Beilstein J. Org. Chem. 2014, 10, 2122–2130, doi:10.3762/bjoc.10.219

• gram amounts of material. With this new methodology, we explored the effects on crystal packing morphology for the indeno[1,2-b]fluorene-6,12-diones by varying the substituents on the silylethynyl groups. Keywords: crystal packing; electron accepting; indenofluorenes; organic electronics; polycyclic

Supercritical carbon dioxide: a solvent like no other

• Jocelyn Peach and
• Julian Eastoe

Beilstein J. Org. Chem. 2014, 10, 1878–1895, doi:10.3762/bjoc.10.196

• microemulsions. Investigations were carried out with a range of ethylene oxide (EO) repeat units, with an inversion of emulsion morphology from water-in-carbon dioxide to carbon dioxide-in-water as EO repeat units increased from 2 to 7. There was noteworthy stability at EO7 thought to be due to the strong

• polyoxypropylene (PPO) unit edged by two hydrophilic polyoxyethylene (PEO) units (Table 2, compound 29). It is hypothesised that the increased hydrophobic interaction of the internal PPO blocks with CO2 during addition is responsible for the change in morphology. These polymeric micelles differ slightly from those

• known that rhyd of the M+ ion can impact preferred curvature and therefore impact surfactant morphology, and exchanging counterion induces a change in effective ion size through the hydrated radius (Figure 6). The study indicated that micelles in water and CO2 should have a range of geometric packing

Sacrolide A, a new antimicrobial and cytotoxic oxylipin macrolide from the edible cyanobacterium Aphanothece sacrum

• Naoya Oku,
• Miyako Matsumoto,
• Kohsuke Yonejima,
• Keijiroh Tansei and
• Yasuhiro Igarashi

Beilstein J. Org. Chem. 2014, 10, 1808–1816, doi:10.3762/bjoc.10.190

• inhibitory concentration (MIC). Cytotoxicity testing and cell morphology observation The cytotoxicity against 3Y1-B clone 1-6 rat fibroblasts and the action of sacrolide A (1) on the morphology of the same cell line were evaluated by the procedures described in [22]. Method to precook raw alga for the

Improving the reactivity of phenylacetylene macrocycles toward topochemical polymerization by side chains modification

• Simon Rondeau-Gagné,
• Jules Roméo Néabo,
• Maxime Daigle,
• Katy Cantin and
• Jean-François Morin

Beilstein J. Org. Chem. 2014, 10, 1613–1619, doi:10.3762/bjoc.10.167

• heating the gel from 223 to 298 K, an endotherm was observed in both cases, which is closely related to the melting point of free cyclohexane [39]. To explore the morphology of the structures created during the gel formation, scanning electron microscopy (SEM) was performed on PAM2 only since PAM3 did not