Peptoids and polyamines going sweet: Modular synthesis of glycosylated peptoids and polyamines using click chemistry

• Daniel Fürniss,
• Timo Mack,
• Frank Hahn,
• Sidonie B. L. Vollrath,
• Katarzyna Koroniak,
• Ute Schepers and
• Stefan Bräse

Beilstein J. Org. Chem. 2013, 9, 56–63, doi:10.3762/bjoc.9.7

• biomacromolecules at high concentrations of strong acids, a polystyrene resin was chosen that contains a tritylchloride linker. The resin was obtained by treatment of Merrifield resin with p-hydroxytriphenylmethyl alcohol and subsequent chlorination [49][50]. This tritylchloride linker allowed a mild cleavage of

Influence of cyclodextrin on the solubility and the polymerization of (meth)acrylated Triton^® X-100

• Melanie Kemnitz and
• Helmut Ritter

Beilstein J. Org. Chem. 2012, 8, 2176–2183, doi:10.3762/bjoc.8.245

• /min. For detection a Viscotek VE 3500 RI detector was used. The system was calibrated with polystyrene standards within a molecular range from 575 to 3,114,000 g/mol. On a Mettler Toledo DSC 822 instrument the DSC measurements were determined in a range of −50 to 200 °C at the heating rate of 10 °C

Hydrophobic analogues of rhodamine B and rhodamine 101: potent fluorescent probes of mitochondria in living C. elegans

• Laurie F. Mottram,
• Safiyyah Forbes,
• Brian D. Ackley and
• Blake R. Peterson

Beilstein J. Org. Chem. 2012, 8, 2156–2165, doi:10.3762/bjoc.8.243

• 2.5% (w/v) polystyrene beads (50 nm, Bangs Laboratory) to prevent movement. Imaging employed an Olympus FV1000 laser scanning confocal microscope and Fluoview software. Images were acquired with Plan-apochromat objectives. Structures of known fluorophores (1–8) and novel hydrophobic analogues of

• coefficients. Differential interference contrast (DIC, left panels) and confocal laser scanning (right panels) micrographs of living C. elegans (20× objective) treated with synthetic compounds for 2 h followed by transfer to an imaging pad containing polystyrene beads for immobilization. The weak signal

• HRB (9, 1 nM) for 2 h followed by immobilization on an agarose pad containing polystyrene beads. Frames were acquired every 3.3 seconds, and are animated at 3 frames per second. The animal in the video is oriented such that the ventral side is left and the anterior is toward the top of the frame. The

New enzymatically polymerized copolymers from 4-tert-butylphenol and 4-ferrocenylphenol and their modification and inclusion complexes with β-cyclodextrin

• Adam Mondrzyk,
• Beate Mondrzik,
• Sabrina Gingter and
• Helmut Ritter

Beilstein J. Org. Chem. 2012, 8, 2118–2123, doi:10.3762/bjoc.8.238

• polystyrene standards in a range of 575 to 3,114,000 g/mol. Toluene was used as the internal standard. Dynamic light scattering (DLS) experiments were carried out with a Malvern Zetasizer Nano ZS ZEN 3600 at a temperature of 20 °C. The particle size distribution was derived from a deconvolution of the

Modulating the activity of short arginine-tryptophan containing antibacterial peptides with N-terminal metallocenoyl groups

• H. Bauke Albada,
• Alina-Iulia Chiriac,
• Michaela Wenzel,
• Maya Penkova,
• Julia E. Bandow,
• Hans-Georg Sahl and
• Nils Metzler-Nolte

Beilstein J. Org. Chem. 2012, 8, 1753–1764, doi:10.3762/bjoc.8.200

• short, Fmoc-protected amino acids were coupled in a solid-state synthesis scheme using HOBt, TBTU, and DiPEA under microwave irradiation. Using suitably protected amino acids, i.e., Fmoc-Arg(Pbf)-OH, Fmoc-Trp(Boc)-OH, and Fmoc-Lys(Boc)-OH, and polystyrene-based resin decorated with Fmoc-protected Rink

The Amadori rearrangement as glycoconjugation method: Synthesis of non-natural C-glycosyl type glycoconjugates

• Katharina Gallas,
• Gerit Pototschnig,
• Florian Adanitsch,
• Arnold E. Stütz and
• Tanja M. Wrodnigg

Beilstein J. Org. Chem. 2012, 8, 1619–1629, doi:10.3762/bjoc.8.185

• surfaces (glycosylated surfaces, e.g., “glyco-chips”, gold, polystyrene plates, glass, nanoparticles), or labelling and imaging of carbohydrates (fluorescence markers, biotin, photolabelling) [27][28]. Herein we describe the application of the Amadori rearrangement as a key step for the synthesis of non

Synthesis and characterization of low-molecular-weight π-conjugated polymers covered by persilylated β-cyclodextrin

• Aurica Farcas,
• Ana-Maria Resmerita,
• Andreea Stefanache,
• Mihaela Balan and
• Valeria Harabagiu

Beilstein J. Org. Chem. 2012, 8, 1505–1514, doi:10.3762/bjoc.8.170

• . The molecular weights of copolymers were determined by gel permeation chromatography (GPC) in CH2Cl2 by using a Water Associates 440 instrument and polystyrene calibrating standards. Differential scanning calorimetry (DSC) was performed with a Mettler Toledo DSC-12E calorimeter with two repeated

Interaction of cyclodextrins with pyrene-modified polyacrylamide in a mixed solvent of water and dimethyl sulfoxide as studied by steady-state fluorescence

• Akihito Hashidzume,
• Yongtai Zheng and
• Akira Harada

Beilstein J. Org. Chem. 2012, 8, 1312–1317, doi:10.3762/bjoc.8.150

• TOSOH CCP & 8020 system equipped with two TOSOH TSKgel α-M columns connected in series, using formamide as the eluent at a flow rate of 0.3 mL min−1. TOSOH UV-8020 and TOSOH RI-8021 detectors were used. The molecular weights were calibrated by polystyrene sulfonate sodium-salt samples (American Polymer

Synthesis of diverse indole libraries on polystyrene resin – Scope and limitations of an organometallic reaction on solid supports

• Kerstin Knepper,
• Sylvia Vanderheiden and
• Stefan Bräse

Beilstein J. Org. Chem. 2012, 8, 1191–1199, doi:10.3762/bjoc.8.132

• -polystyrene (1{h}) with 1-methyl-1-propenylmagnesiumbromide (2{b}), an optimum between −20 and 0 °C was determined (Figure 2). In over 90% of the cases, the purities of the crude material after cleavage were above 80%, and in a few cases even over 90% (according to GC-MS) [24]. Pure material was obtained

• after thin-layer chromatography. A slightly higher temperature was optimal for the reaction of (3-methyl-4-nitrophenyl)carboxymethyl-polystyrene (1{i}) with the less active vinyl magnesium bromide 2{a} (Figure 3). In addition to this, we also varied the amount of Grignard reagent for the reaction of 1{h

• calculated as if complete conversion had taken place. GP 3 - Suzuki reaction: Under an argon atmosphere, one equiv of the respective 7-bromo-1H-indole-6-carboxymethyl-polystyrene is suspended in DMF (0.1 mmol/mL) together with 0.10 equiv of tetrakis(triphenylphosphine)palladium and two equiv of boronic acid

Combined bead polymerization and Cinchona organocatalyst immobilization by thiol–ene addition

• Kim A. Fredriksen,
• Tor E. Kristensen and
• Tore Hansen

Beilstein J. Org. Chem. 2012, 8, 1126–1133, doi:10.3762/bjoc.8.125

• transformation. Undeniably, polymer beads prepared without any Cinchona organocatalyst present did also catalyze the reaction. However, we found that several other polymer resins, such as unmodified Merrifield resin (chloromethylated and cross-linked polystyrene), influence the reaction in the same manner

Formation of carbohydrate-functionalised polystyrene and glass slides and their analysis by MALDI-TOF MS

• Martin J. Weissenborn,
• Johannes W. Wehner,
• Christopher J. Gray,
• Robert Šardzík,
• Claire E. Eyers,
• Thisbe K. Lindhorst and
• Sabine L. Flitsch

Beilstein J. Org. Chem. 2012, 8, 753–762, doi:10.3762/bjoc.8.86

• of Organic Chemistry, Christiana Albertina University of Kiel, Otto-Hahn-Platz 3/4, 24098 Kiel, Germany 10.3762/bjoc.8.86 Abstract Glycans functionalised with hydrophobic trityl groups were synthesised and adsorbed onto polystyrene and glass slides in an array format. The adsorbed glycans could be

• ligands, such as protein, peptide and carbohydrate arrays [2][3]. An important aspect of this field is the immobilisation of such ligands on solid array surfaces, which can be polymers, such as polystyrene, or glass or gold, i.a. [4][5][6][7]. The challenge for immobilisations is in the efficiency of

• or attachment of a hydrophobic tether. The latter has been used highly successfully by the Feizi group as part of the neoglycolipid array technology [8]. More recently, two groups [7][9] have reported the application of hydrophobic tethers for binding to polystyrene slides for glycan analysis

Azobenzene dye-coupled quadruply hydrogen-bonding modules as colorimetric indicators for supramolecular interactions

• Yagang Zhang and
• Steven C. Zimmerman

Beilstein J. Org. Chem. 2012, 8, 486–495, doi:10.3762/bjoc.8.55

• the possibility of using these compounds as colorimetric indicators, two types of polymers bearing DAN and UPy were used (Figure 4). The DAN modified polystyrene (PS-DAN) was a gift from Dr. Cyrus Anderson and its synthesis will be published elsewhere. Commercially available polystyrene (PS) was used

• temperature. Chemical structures of UPy dimer and DAN complexes with UG and DeUG. Illustration of the use of DeUG-Dye and DAN-Dye as colorimetric indicators for supramolecular interactions through specific quadruply hydrogen-bonding interactions. Top: DeUG-Dye interacts with DAN modified polystyrene (PS

Synthesis of mesomeric betaine compounds with imidazolium-enolate structure

• Nina Gonsior,
• Fabian Mohr and
• Helmut Ritter

Beilstein J. Org. Chem. 2012, 8, 390–397, doi:10.3762/bjoc.8.42

• used. The system was calibrated with polystyrene standards with a molecular range from 580 Da to 1186 kDa. Synthesis of 2,3-dibromo-5-(1-butyl-1H-imidazol-3-ium-3-yl)-1,4-benzoquinone-6-olate (3) Tetrabromo-1,4-benzoquinone (p-bromanil, 1) (0.845 g, 2 mmol) was dissolved in 45 mL of acetonitrile at 60

Synthesis and photooxidation of styrene copolymer bearing camphorquinone pendant groups

• Branislav Husár,
• Norbert Moszner and
• Ivan Lukáč

Beilstein J. Org. Chem. 2012, 8, 337–343, doi:10.3762/bjoc.8.37

• formed in irradiated films of styrene copolymers with pendant BZ groups leads to crosslinking, only small molecular-weight changes in irradiated MCQ/S were observed. Keywords: camphorquinone; 1,2-diketone; (±)-10-methacryloyloxycamphorquinone; photooxidation; polystyrene; Introduction Camphorquinone

• subsequent reactions leading to photoproducts [21]. The rate-determining step in photoinitiation by CQ/amine is hydrogen transfer by the excited n→π* triplet state of the carbonyl group of CQ from the alkylamino group [8][9]. The photochemistry of the low molecular CQ in the polystyrene (PS) film was the

Ion-exchange-resin-catalyzed adamantylation of phenol derivatives with adamantanols: Developing a clean process for synthesis of 2-(1-adamantyl)-4-bromophenol, a key intermediate of adapalene

• Nan Wang,
• Ronghua Wang,
• Xia Shi and
• Gang Zou

Beilstein J. Org. Chem. 2012, 8, 227–233, doi:10.3762/bjoc.8.23

• -adamantylphenol derivatives in acetic acid using a commercially available, strongly acidic cross-linked polystyrene-type sulfonic acid resin as a recyclable catalyst. The features of this process include (a) an almost waste-free procedure, except for the regeneration of the resin catalyst at its first use, after

Sexithiophenes as efficient luminescence quenchers of quantum dots

• Christopher R. Mason,
• Yang Li,
• Paul O’Brien,
• Neil J. Findlay and
• Peter J. Skabara

Beilstein J. Org. Chem. 2011, 7, 1722–1731, doi:10.3762/bjoc.7.202

• LEDs and photovoltaic cells [19][20][21][22][23]. Previously, we reported the synthesis and characterisation of CdS quantum dots in polystyrene beads, in which beads ranging in size from 100 nm to 500 μm were prepared and confocal microscopy showed an even distribution of CdS throughout the polymer

The application of a monolithic triphenylphosphine reagent for conducting Appel reactions in flow microreactors

• Kimberley A. Roper,
• Heiko Lange,
• Anastasios Polyzos,
• Malcolm B. Berry,
• Ian R. Baxendale and
• Steven V. Ley

Beilstein J. Org. Chem. 2011, 7, 1648–1655, doi:10.3762/bjoc.7.194

• both the solution or solid-phase reactions (5% with solution-based triphenylphosphine and 18–29% with solid-supported triphenylphosphine), indicating that path B is the major pathway in either case [40][43]. Using a polystyrene-based triphenylphosphine monolith we hoped to benefit from the accelerated

Continuous-flow enantioselective α-aminoxylation of aldehydes catalyzed by a polystyrene-immobilized hydroxyproline

• Xacobe C. Cambeiro,
• Rafael Martín-Rapún,
• Pedro O. Miranda,
• Sonia Sayalero,
• Esther Alza,
• Patricia Llanes and
• Miquel A. Pericàs

Beilstein J. Org. Chem. 2011, 7, 1486–1493, doi:10.3762/bjoc.7.172

• Franqués, 1. E-08028, Barcelona, Spain 10.3762/bjoc.7.172 Abstract The application of polystyrene-immobilized proline-based catalysts in packed-bed reactors for the continuous-flow, direct, enantioselective α-aminoxylation of aldehydes is described. The system allows the easy preparation of a series of β

• -aminoxy alcohols (after a reductive workup) with excellent optical purity and with an effective catalyst loading of ca. 2.5% (four-fold reduction compared to the batch process) working at residence times of ca. 5 min. Keywords: α-aminoxylation; continuous flow; packed-bed reactors; polystyrene

• prominent position is occupied by catalysts covalently immobilized onto insoluble, cross-linked polymers [37][38][39][40]. An interesting development arising from this strategy is the polystyrene-immobilized 4-hydroxyproline 1a (Figure 1), reported by our group as an extremely efficient and reusable

Multistep flow synthesis of vinyl azides and their use in the copper-catalyzed Huisgen-type cycloaddition under inductive-heating conditions

• Lukas Kupracz,
• Jan Hartwig,
• Jens Wegner,
• Sascha Ceylan and
• Andreas Kirschning

Beilstein J. Org. Chem. 2011, 7, 1441–1448, doi:10.3762/bjoc.7.168

• under flow conditions A glass reactor (12 cm length and 8.5 mm internal diameter) filled with polymer-bound iodate(I) complex 5 (5 g; theoretical loading = 3.5 mmol/g) and a second identical flow reactor, which was filled with a slurry of polystyrene-bound 1,8-diaza-[5.4.0]bicyclo-7-undecene (8) (4 g

Efficient and selective chemical transformations under flow conditions: The combination of supported catalysts and supercritical fluids

• M. Isabel Burguete,
• Eduardo García-Verdugo and
• Santiago V. Luis

Beilstein J. Org. Chem. 2011, 7, 1347–1359, doi:10.3762/bjoc.7.159

• also be driven towards the branched aldehyde. In this case, the resulting compound has a stereogenic center and an enantioselective process can be developed using a chiral catalyst. An example was reported by Shibahara et al. [59]. For this purpose, a chiral catalyst based on polystyrene-supported (PS

• the enantioselective cyclopropanation with supported copper–bisoxazoline (Cu–BOX) or copper-pyridineoxazoline (Cu–PyOX) complexes and related systems. The oxazoline ligands can be introduced in polystyrene–divinylbenzene (PS–DVB) matrices either by grafting, by reaction with chloromethyl groups of

Novel carbazole–pyridine copolymers by an economical method: synthesis, spectroscopic and thermochemical studies

• Aamer Saeed,
• Madiha Irfan and
• Shahid Ameen Samra

Beilstein J. Org. Chem. 2011, 7, 638–647, doi:10.3762/bjoc.7.75

• was also observed consistent with the in situ formation of the pyridine ring and polymerization. Polymer solutions in THF were subjected to GPC using polystyrene standards for the determination of the molecular weights, however, no elution was observed for any of the polymers. Therefore, molecular

Air-stable, recyclable, and time-efficient diphenylphosphinite cellulose-supported palladium nanoparticles as a catalyst for Suzuki–Miyaura reactions

• Qingwei Du and
• Yiqun Li

Beilstein J. Org. Chem. 2011, 7, 378–385, doi:10.3762/bjoc.7.48

• ligands [23][24][25] or palladium(0) nanoparticles on various solid supports [26][27][28][29][30][31] (polystyrene [26], silica [27], cellulose [28], corn starch [29], polymethyl methacrylate [30] and others [31]). In addition, cellulose as efficient support for Pd nanoparticles in other cross-coupling

Chiral recognition of macromolecules with cyclodextrins: pH- and thermosensitive copolymers from N-isopropylacrylamide and N-acryloyl-D/L-phenylalanine and their inclusion complexes with cyclodextrins

• Sabrina Gingter,
• Ella Bezdushna and
• Helmut Ritter

Beilstein J. Org. Chem. 2011, 7, 204–209, doi:10.3762/bjoc.7.27

• °. Measured solutions contained 1 mg/mL substance in water and were performed in a polystyrene cuvette with a layer thickness of 1 cm. Measurement results are calculated by the non-negative least-squares (NNLS) algorithm. Depending on measurement, number- or volume-averaged diameters are used for

• Viscotek TSK GMHHR-M 7.8 mm (ID) × 30 cm (L) columns at 60 °C. N,N-Dimethylformamide (DMF, 0.1 M LiCl) was used as eluent at a flow rate of 1 mL·min−1. A Viscotek VE 3500 RI detector and a Viscotek Viscometer model 250 were used. The system was calibrated with polystyrene standards with a molecular range

Synthesis of cationic dibenzosemibullvalene-based phase-transfer catalysts by di-π-methane rearrangements of pyrrolinium-annelated dibenzobarrelene derivatives

• Heiko Ihmels and
• Jia Luo

Beilstein J. Org. Chem. 2011, 7, 119–126, doi:10.3762/bjoc.7.17

• . H. Bodenstedt, Organic Chemistry I, University of Siegen. TLC analyses were performed on silica-gel sheets (Macherey-Nagel Polygram Sil G/UV254). Unless otherwise noted, commercially available chemicals were reagent grade and used without further purification. Polymer-bound DBU (polystyrene cross

Hoveyda–Grubbs type metathesis catalyst immobilized on mesoporous molecular sieves MCM-41 and SBA-15

• Hynek Balcar,
• Tushar Shinde,
• Naděžda Žilková and
• Zdeněk Bastl

Beilstein J. Org. Chem. 2011, 7, 22–28, doi:10.3762/bjoc.7.4

• polystyrene standards. Grubbs 1 and Hoveyda–Grubbs 2 catalysts. Zhan catalyst-1B. Conversion curves for the RCM of DEDAM with 3 in CH2Cl2 (open squares), 3/SBA-15 in CH2Cl2 (inverted filled triangle), 3/SBA-15 in benzene (filled diamond), 3/SBA-15 in cyclohexane (filled triangle), and for the RCM of 1,7