Glycoscience@Synchrotron: Synchrotron radiation applied to structural glycoscience

• Serge Pérez and
• Daniele de Sanctis

Beilstein J. Org. Chem. 2017, 13, 1145–1167, doi:10.3762/bjoc.13.114

• fractions extracted from never-dried delignified spruce wood. In this case, the observed morphology was of the type “nanostrips” that had a characteristic thickness and width of about 0.5 nm and 4 nm, respectively. The thickness is an indication that the nanostrips are made up of only one monolayer of

Correlation of surface pressure and hue of planarizable push–pull chromophores at the air/water interface

• Frederik Neuhaus,
• Fabio Zobi,
• Gerald Brezesinski,
• Marta Dal Molin,
• Stefan Matile and
• Andreas Zumbuehl

Beilstein J. Org. Chem. 2017, 13, 1099–1105, doi:10.3762/bjoc.13.109

• fluorescent probes are an elegant solution to this problem but it requires first the establishment of a direct correlation between the membrane surface pressure and the induced color change of the probe. Here, we analyze planarizable dithienothiophene push–pull probes in a monolayer at the air/water interface

• liquid crystalline over the entire temperature range measured [10]. What is missing is a quantitative correlation between the surface pressure of a membrane and the spectroscopic properties of the flipper mechanophores [4][8]. Therefore, we have performed Langmuir–Pockels monolayer experiments

• . Monolayers at the air/water interface are well known models for biological membranes, avoiding trans-bilayer leaflet correlation effects [11][12][13][14]. Various techniques exist to probe the surface pressure and the lateral organization of the monolayer [14]. Using monolayers of pure flipper probes, we

Glyco-gold nanoparticles: synthesis and applications

• Federica Compostella,
• Olimpia Pitirollo,
• Alessandro Silvestri and
• Laura Polito

Beilstein J. Org. Chem. 2017, 13, 1008–1021, doi:10.3762/bjoc.13.100

• -workers [28]. AuNPs were firstly coated by a monolayer of dithiol-cyclooctyne spacer. Then, the alkyne moiety reacted with mannosyl azide through a copper-free strain-promoted alkyne-azide cycloaddition (SPAAC), affording the GAuNPs. Alternatively, Yan and co-workers developed a three-step photocoupling

• procedure for the immobilization of carbohydrates on the nanoparticles surface [27]. The AuNPs were firstly coated with a PFPA-thiol monolayer via a ligand-exchange reaction, then carbohydrates were immobilized by means of a photocoupling reaction. Glyco-gold nanoparticles: design and structural properties

• determination of the binding selectivity for human and avian influenza (H1N1 and H7N9), by using modified glycans (lactose, α(2,3)Neu5AcLacNAc and α(2,6)Neu5AcLacNAc) to introduce the active moieties on the gold monolayer. The SERS spectra registered with changes in the 1400–1600 and 1000–1200 cm−1 bands were

Interactions between shape-persistent macromolecules as probed by AFM

• Johanna Blass,
• Jessica Brunke,
• Franziska Emmerich,
• Cédric Przybylski,
• Vasil M. Garamus,
• Artem Feoktystov,
• Roland Bennewitz,
• Gerhard Wenz and
• Marcel Albrecht

Beilstein J. Org. Chem. 2017, 13, 938–951, doi:10.3762/bjoc.13.95

• of the CD polymer and a reactive isothiocyanate–silane monolayer. Atomic force measurements of CD polymer decorated surfaces show enhanced supramolecular interaction energies which can be attributed to multiple inclusion complexes based on the rigidity of the polymer backbone and the regular

• well as the silicon AFM tip, were first functionalized by a polysiloxane monolayer bearing isothiocyanate groups, which smoothly react with amines forming stable thiourea links [48]. Monolayers of β-CD or β-CD-polymer were obtained by attachment of monoamino β-CD or amino-modified CD polymer 12

• and CD because of the higher regularity of the CD spacing at the polymer compared to the spacing within the CD monolayer. We conclude that the regularity of the CD polymer 12 allows to establish a much higher number of supramolecular bonds with the connector 9 giving rise to about a fivefold

Sulfamide chemistry applied to the functionalization of self-assembled monolayers on gold surfaces

• Loïc Pantaine,
• Vincent Humblot,
• Vincent Coeffard and
• Anne Vallée

Beilstein J. Org. Chem. 2017, 13, 648–658, doi:10.3762/bjoc.13.64

• increase of the hydrophilicity of the surface, which is in agreement with the formation of an amino-terminated monolayer [19]. SAM a (4-MeC6H4SO2NHOSO2-4-MeC6H4) and SAM b (4-FC6H4SO2NHOSO2-4-FC6H4) exhibit both a similar contact angle around 65 ± 2° showing a more hydrophobic nature of the SAMs after the

• heterogeneous, thus the hydrophobic end groups resulting of the coupling reaction are in the outer part of the monolayer and are free to become disordered [43]. Moreover, the F end group is smaller than the CH3 one and thus may be more flexible, inducing a more disordered layer and lowered hydrophobic

• ) δ 20.2 (2C), 118.6 (4C), 119.1 (4C), 129.2 (2C), 129.4 (4C), 130.5 (4C), 132.3 (2C), 135.2 (2C), 138.6 (2C); IR (neat): 3291, 3031, 2918, 2857, 1449, 1329, 1150, 903, 807, 622, cm-1; HRMS–ESI (m/z): [M + H]+ calcd for C26H27N4O4S4 587.0915, found: 587.0920. Monolayer preparation A solution of 4

Fast and efficient synthesis of microporous polymer nanomembranes via light-induced click reaction

• Qi An,
• Youssef Hassan,
• Xiaotong Yan,
• Peter Krolla-Sidenstein,
• Tawheed Mohammed,
• Mathias Lang,
• Stefan Bräse and
• Manuel Tsotsalas

Beilstein J. Org. Chem. 2017, 13, 558–563, doi:10.3762/bjoc.13.54

• the substrates with an alkyne terminated self-assembled monolayer, which presents initial groups for the stepwise growing of the CMPs using the TYC reaction. In the first step, we immersed the functionalized surface in a solution of the tetra-topic thiol building block (tetrakis(4-sulfanylphenyl

• ; spring constant: 3.5 N/m). Self-assembled monolayer (SAM) preparation: For SAM formation, a clean gold substrate (2.2 cm × 2.2 cm) was rinsed with absolute ethanol and then immersed in a solution of S-[11-oxo-11-(propargylamino)undecyl] thioacetate (AcSC10H20C(O)NHCH2C≡CH) (with a concentration of 1 mmol

Organic chemistry meets polymers, nanoscience, therapeutics and diagnostics

• Vincent M. Rotello

Beilstein J. Org. Chem. 2016, 12, 1638–1646, doi:10.3762/bjoc.12.161

• one step further, we created a nanoparticle with a mixed monolayer consisting of hydrogen bonding and aromatic staking sidechains. When we incubated this NP with flavin we observed an increase in binding over time, i.e., we were able to template the particle to the guest [22]. We have since

Syntheses of dibenzo[d,d']benzo[2,1-b:3,4-b']difuran derivatives and their application to organic field-effect transistors

• Minh Anh Truong and
• Koji Nakano

Beilstein J. Org. Chem. 2016, 12, 805–812, doi:10.3762/bjoc.12.79

• Si/SiO2 substrate (Tsub = 90 °C), which demonstrated the highest mobility in this study. The layer structure was confirmed with a monolayer thickness (d-spacing) of 3.94 nm (2θ = 2.24°). Molecular lengths with extended linear alkyl chains are expected to be ca. 4.2 nm. Accordingly, syn-DNBDF 6 should

Preparation of Pickering emulsions through interfacial adsorption by soft cyclodextrin nanogels

• Shintaro Kawano,
• Toshiyuki Kida,
• Mitsuru Akashi,
• Hirofumi Sato,
• Motohiro Shizuma and
• Daisuke Ono

Beilstein J. Org. Chem. 2015, 11, 2355–2364, doi:10.3762/bjoc.11.257

• top layer (Figure 7C-1) and the bottom substrate (Figure 7C-2) is about 46 nm, suggesting that the original nanogel particles (30 to 50 nm in diameter) self-assemble at the oil–water interface to form interconnected monolayers. Hence, the Pickering emulsion should be fabricated from the monolayer

Trifluoromethyl-substituted tetrathiafulvalenes

• Olivier Jeannin,
• Frédéric Barrière and
• Marc Fourmigué

Beilstein J. Org. Chem. 2015, 11, 647–658, doi:10.3762/bjoc.11.73

• bond interactions [24][25][26][27]. Within such TTF derivatives, as reported by Bryce [28], an internal charge transfer (ICT) between the TTF and the EWG moieties increases the hydrophilicity of the TTF head groups and facilitates monolayer formation on the water surface for the preparation of Langmuir

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

• monolayer is demonstrated by the apparent permeability coefficients in Figure 5 (see Supporting Information File 1 for full experimental data). Results indicate that in terms of permeability coefficients, there is a significant difference between the formulations and free CPT (CPT in DMSO) (P < 0.05

Organic chemistry on surfaces: Direct cyclopropanation by dihalocarbene addition to vinyl terminated self-assembled monolayers (SAMs)

• Malgorzata Adamkiewicz,
• David O’Hagan and
• Georg Hähner

Beilstein J. Org. Chem. 2014, 10, 2897–2902, doi:10.3762/bjoc.10.307

• approaches are taken to achieve surface modification as illustrated in Figure 1. The first involves incorporating pre-functionalised alkylsilanes/alkylthiols carrying functional groups (FG) to generate the SAM directly, whereas the second approach involves chemical modification of a pre-assembled monolayer

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

• molecular geometries and their supramolecular monolayer and multilayer formation on HOPG. Results and Discussion We started our STM investigations on the MSW 2 using TCB as a standard solvent for STM, but did not observe molecules, most probably because they do not adsorb to form two-dimensional (2D

• , related to high and low tunneling currents, respectively [13]. At the OA/HOPG interface 1 forms a 2D-crystalline monolayer (Figure 2a and b) for which a hexagonal unit cell of a = b = 6.7 ± 0.2 nm, γ(a,b) = 60 ± 2° can be indexed. The unit cell vector a is oriented with γ(a,d1) = 9 ± 2° relative to one of

• was thermally annealed for 30 s at 80 °C. (a)–(c) STM images and a supramolecular model of MSW 2 at the OA/HOPG interface. (a) Overview STM image (200 × 200 nm2 (internal scanner calibration), VS = −1.4 V, It = 5 pA). A several 10 × 10 nm2 large region is covered by a monolayer and (partly) a

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

• -dimensional (2D) crystalline monolayer patterns are obtained by in situ scanning tunneling microscopy. A concentration-dependent conformational polymorphism is found, and open and more dense packing motifs are observed. For all three compounds alike lattice parameters are found, therefore the intermolecular

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

• . This seemed logical as each CD monolayer was assumed to be independent of the other without interaction between the adjacent adsorbed VOCs and more importantly, a saturation point must exist at which point the coating cannot further adsorb VOCs. Hence, it was predicted that a surplus of 20 times the

Lateral ordering of PTCDA on the clean and the oxygen pre-covered Cu(100) surface investigated by scanning tunneling microscopy and low energy electron diffraction

• Stefan Gärtner,
• Benjamin Fiedler,
• Oliver Bauer,
• Antonela Marele and
• Moritz M. Sokolowski

Beilstein J. Org. Chem. 2014, 10, 2055–2064, doi:10.3762/bjoc.10.213

• significant density of nucleation defects is found pointing to a strong interaction of PTCDA with Cu(100). Quite differently, after preadsorption of oxygen and formation of the (√2 × 2√2)R45° – 2O/Cu(100) superstructure on Cu(100), PTCDA forms an incommensurate monolayer with a structure that corresponds well

• . The coverages (θ) were determined from the evaluation of STM images, and in the following one monolayer (1 ML) refers to a coverage equivalent to that of the ordered first layer. The preparation chamber was also equipped with a microchannel plate low energy electron diffraction apparatus (MCP-LEED

• measurements from Andreasson et al. of PTCDA on Cu(100) can also be interpreted in this way [9], although these results have to be taken with some caution, because of the different structure they found. The ordering of the second layer of PTCDA on Cu(100) with the same commensurate structure as the monolayer

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

• models have been used to attempt to predict and quantify CO2-philicity. One very popular approach is the concept of fraction free volume, or FFV, defined by Johnston et al. [78]. The fractional free volume of an adsorbed monolayer is calculated from surfactant tail geometry and surface coverage, using

Biantennary oligoglycines and glyco-oligoglycines self-associating in aqueous medium

• Svetlana V. Tsygankova,
• Alexander A. Chinarev,
• Alexander B. Tuzikov,
• Nikolai Severin,
• Alexey A. Kalachev,
• Juergen P. Rabe,
• Alexandra S. Gambaryan and
• Nicolai V. Bovin

Beilstein J. Org. Chem. 2014, 10, 1372–1382, doi:10.3762/bjoc.10.140

• formation of a monolayer with the monomer conformation ”2 + 0” is favorable according to molecular dynamics simulations [13]. Minimal size of Glyn fragment providing association In the case of biantennary molecules association formally starts from the value n = 4, but, in fact, this value is supposedly

• unstoppable at the stage of the monolayer formation. At the same time, monolayer tectomers are exclusively formed in basic solutions. Concentration range Most parts of the experiments were carried out in the concentration range of 0.1–1.0 mg/mL. A concentration of 0.1 mg/mL was used for the adequate

Molecular recognition of surface-immobilized carbohydrates by a synthetic lectin

• Melanie Rauschenberg,
• Eva-Corrina Fritz,
• Christian Schulz,
• Tobias Kaufmann and
• Bart Jan Ravoo

Beilstein J. Org. Chem. 2014, 10, 1354–1364, doi:10.3762/bjoc.10.138

• wide range of physiological processes and the development of synthetic carbohydrate receptors (“synthetic lectins”) constitutes a key advance in biomedical technology. In this article we report a synthetic lectin that selectively binds to carbohydrates immobilized in a molecular monolayer. Inspired by

• ]. Our group has shown that also simple carbohydrate microarrays can be conveniently prepared by μCP if reactive glycosides are printed on a suitable target self-assembled monolayer (SAM) [31][32]. Amongst others, we reported carbohydrate microarrays fabricated by cycloaddition of alkynes on azide

Synthesis and characterization of novel bioactive 1,2,4-oxadiazole natural product analogs bearing the N-phenylmaleimide and N-phenylsuccinimide moieties

• Catalin V. Maftei,
• Elena Fodor,
• Peter G. Jones,
• M. Heiko Franz,
• Gerhard Kelter,
• Heiner Fiebig and
• Ion Neda

Beilstein J. Org. Chem. 2013, 9, 2202–2215, doi:10.3762/bjoc.9.259

• analogs 4 and 7 were then tested for antitumor activity toward a panel of 11 cell lines in vitro by using a monolayer cell-survival and proliferation assay. Compound 7 was the most potent and exhibited a mean IC50 value of approximately 9.4 µM. Aniline 1 was synthesized by two routes in one-pot reactions

• C–H···O and one three-centre (N–H, C–H)···O interaction. The double bond has a Z-configuration. Antitumor activity The in vitro antitumor activity of six synthesized compounds toward a panel of 11 cell lines was assessed by using a monolayer cell survival and proliferation assay. By exhibiting a

• -phenylmaleimide or N-phenylsuccinimide moieties were synthesized in two steps starting from 1,2,4-oxadiazole amine 1. All intermediate derivatives were isolated, characterized and tested in vitro for antitumor activity toward a panel of 11 cell lines by using a monolayer cell survival and proliferation assay

Gallium-containing polymer brush film as efficient supported Lewis acid catalyst in a glass microreactor

• Rajesh Munirathinam,
• Roberto Ricciardi,
• Richard J. M. Egberink,
• Jurriaan Huskens,
• Michael Holtkamp,
• Herbert Wormeester,
• Uwe Karst and
• Willem Verboom

Beilstein J. Org. Chem. 2013, 9, 1698–1704, doi:10.3762/bjoc.9.194

• a flat silicon oxide surface in order to optimize the reaction conditions before attempting the functionalization of a microreactor. Polystyrene sulfonate (PSS) polymer brushes [19] were synthesized according to the procedure summarized in Scheme 2. First, a monolayer of atom transfer radical

Towards a biocompatible artificial lung: Covalent functionalization of poly(4-methylpent-1-ene) (TPX) with cRGD pentapeptide

• Lena Möller,
• Christian Hess,
• Jiří Paleček,
• Yi Su,
• Axel Haverich,
• Andreas Kirschning and
• Gerald Dräger

Beilstein J. Org. Chem. 2013, 9, 270–277, doi:10.3762/bjoc.9.33

• the formation of a confluent endothelial cell monolayer was observed on both the cRGD as well as albumin/heparin-modified membranes. In contrast, no adherent cells could be found on the unmodified membranes 2. To verify that the observed effect is in fact only RGD-mediated, membranes obtained during

Control over molecular motion using the cis–trans photoisomerization of the azo group

• Estíbaliz Merino and
• María Ribagorda

Beilstein J. Org. Chem. 2012, 8, 1071–1090, doi:10.3762/bjoc.8.119

• results in a collective structural change in a certain direction. This cooperative molecular motion of SAMazo acts as a molecular lift capable of lifting one Hg drop deposited on the monolayer of azobenzenes. Furthermore, this device acts as a photoswitch of the current between the Au(111) layer and the

Multistep organic synthesis of modular photosystems

• Naomi Sakai and
• Stefan Matile

Beilstein J. Org. Chem. 2012, 8, 897–904, doi:10.3762/bjoc.8.102

• surface of monolayer 48 were removed with DTT to afford free thiols on the surface of monolayer 49. For SOSIP [18][19], the concentration of propagators had to be optimized to a critical SOSIP concentration, cSOSIP. Below cSOSIP, ring-opening disulfide-exchange polymerization [27] does not occur, whereas

• propagator, the temperature, the presence of oxygen in the solution and, most importantly, the composition of the solvent mixture used. For propagator 3, cSOSIP = 3.5 mM was found in a 1:1 mixture of chloroform and methanol with 100 mM DIPEA as a base catalyst. Incubation of monolayer 49 in this solution

• structures (Scheme 4 and Scheme 5). We thus summarize both processes in schematic form (Scheme 6). To recapitulate briefly from this perspective, we repeat that the solid-phase synthesis begins with the deposition of initiator 2 on ITO. Activation of monolayer 48 with DTT produces monolayer 49 with free

An easily accessible sulfated saccharide mimetic inhibits in vitro human tumor cell adhesion and angiogenesis of vascular endothelial cells

• Grazia Marano,
• Claas Gronewold,
• Martin Frank,
• Anette Merling,
• Christian Kliem,
• Sandra Sauer,
• Manfred Wiessler,
• Eva Frei and
• Reinhard Schwartz-Albiez

Beilstein J. Org. Chem. 2012, 8, 787–803, doi:10.3762/bjoc.8.89

• migration assay, we observed the effect of GSF on migration of the human melanoma lines WM-115 and WM-266-4 into a wound scratched into an intact cell monolayer. The migration rates of the two untreated cell lines are clearly different. While WM-115 cells from the original tumor needed about 24 h for the