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

• synthesize also 1,3,4,6-tetra-O-acetyl-N-azidoacetyl-D-galactosamine (Ac4GalNAz = 2) and 1,3,4,6-tetra-O-acetyl-N-azidoacetyl-D-mannosamine (Ac4ManNAz = 3) with similar yields under these optimized conditions (see Supporting Information File 1). Click reaction on alkynylated polyamines and peptoids The

Chemical–biological characterization of a cruzain inhibitor reveals a second target and a mammalian off-target

• Jonathan W. Choy,
• Clifford Bryant,
• Claudia M. Calvet,
• Patricia S. Doyle,
• Shamila S. Gunatilleke,
• Siegfried S. F. Leung,
• Kenny K. H. Ang,
• Steven Chen,
• Jiri Gut,
• Juan A. Oses-Prieto,
• Jonathan B. Johnston,
• Michelle R. Arkin,
• Alma L. Burlingame,
• Jack Taunton,
• Matthew P. Jacobson,
• James M. McKerrow,
• Larissa M. Podust and
• Adam R. Renslo

Beilstein J. Org. Chem. 2013, 9, 15–25, doi:10.3762/bjoc.9.3

• typical experiment, intracellular T. cruzi amastigotes were treated with 9 for 1 hour, followed by cell lysis, “click” reaction with TAMRA azide 10, and separation/visualization by SDS-PAGE. Regardless of the host cell employed (J774 macrophage, or C2C12), only one prominently labeled band at ≈35 kDa was

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

• of a copolymer of 4-tert-butylphenol and 4-ferrocenylphenol by horse radish peroxidase (HRP) in the presence of H2O2 in a 1,4-dioxane/water system is described. Furthermore, polymer-analogous alkylation of the free hydroxy groups and subsequent click reaction with mono-6-azido-6-desoxy-β-cyclodextrin

• investigated until now. Hence, in the present paper we report the HRP-catalyzed synthesis of novel copolymers from 2 and 3. Click reaction of the propargyl modified polyphenol 5 with mono-(6-azido-6-deoxy)-β-cyclodextrin (6) was also investigated. Based on former studies, host–guest structures were created [24

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

• its recent conceptualization as a “click” reaction [13]. In order to prepare different polymer beads with varying degrees of swelling characteristics, we assembled a small collection of useful thiol and alkene building blocks (Figure 1). Trithiol 4 is a readily available commercial product, whereas

Intramolecular bridges formed by photoswitchable click amino acids

• Christian Hoppmann,
• Ronald Kühne and
• Michael Beyermann

Beilstein J. Org. Chem. 2012, 8, 884–889, doi:10.3762/bjoc.8.100

• a photoswitchable unit elongated with a functional group that allows for a specific click reaction, such as an alkene that can react with the thiol group of a cysteine residue. An intramolecular click reaction results in the formation of a photoswitchable bridge, which can be used for controlling

• a model peptide without a preferred conformation, it was seen that the thiol–ene click reaction takes place efficiently in both cases. Upon induction of an α-helical structure by the addition of trifluoroethanol, the thiol click reaction occurs preferentially with the i,i+4 spacing. Even in the

• presence of glutathione as an additional thiol the click reaction of the PSCaa occurs intramolecularly with the cysteine rather than with the glutathione, indicating that the click reaction may be used even under reducing conditions occurring in living cells. Keywords: azobenzene; helical conformation

High-affinity multivalent wheat germ agglutinin ligands by one-pot click reaction

• Henning S. G. Beckmann,
• Heiko M. Möller and
• Valentin Wittmann

Beilstein J. Org. Chem. 2012, 8, 819–826, doi:10.3762/bjoc.8.91

Thiophene-based donor–acceptor co-oligomers by copper-catalyzed 1,3-dipolar cycloaddition

• Stefanie Potratz,
• Amaresh Mishra and
• Peter Bäuerle

Beilstein J. Org. Chem. 2012, 8, 683–692, doi:10.3762/bjoc.8.76

• high yield and purity. Click reactions generally involve a Cu(I)-catalyzed version of the Huisgen 1,3-dipolar cycloaddition of terminal acetylenes and azides (CuAAC), to regioselectively yield 1,4-disubstituted 1H-1,2,3-triazoles [11][12]. In the meanwhile, this type of click reaction has become very

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

• Huisgen cycloaddition (click reaction). The click approach began with the readily available and inexpensive starting material, 4-aminobenzoic acid (Scheme 4), which was diazotized and treated with phenol to afford 13 in 65% yield, comparable to published procedures [52][53][54]. To install the azide

• -diamido-1,8-naphthyridine (DAN) unit was linked to azobenzene dyes through one of its amide groups, giving compounds 5, 8, and 10, and the 7-deazaguanine urea (DeUG) unit was linked to an azobenzene dye by a Steglich esterification, giving 12, or by the copper-catalyzed azide–alkyne cycloaddition (click

• reaction) to give 18. The synthesis provides access to highly colored recognition units that may serve as useful probes of recognition events. In this work we have successfully demonstrated that these units colored two polymers, PBA and PS, but only when they contain the complementary recognition units

Highly efficient cyclosarin degradation mediated by a β-cyclodextrin derivative containing an oxime-derived substituent

• Michael Zengerle,
• Florian Brandhuber,
• Christian Schneider,
• Franz Worek,
• Georg Reiter and
• Stefan Kubik

Beilstein J. Org. Chem. 2011, 7, 1543–1554, doi:10.3762/bjoc.7.182

• (“click-reaction”) [33] from mono-6-azido-6-deoxy-β-cyclodextrin (4) and a functionalized alkyne (Scheme 3, route B). Conjugations by copper(I)-catalyzed azide–alkyne cycloadditions have become popular in many different fields of chemistry [33][34], including cyclodextrin chemistry [35][36][37][38][39][40

Hyperbranched polyethylenimine bearing cyclodextrin moieties showing temperature and pH controlled dye release

• Indra Böhm,
• Susanne Katharina Kreth and
• Helmut Ritter

Beilstein J. Org. Chem. 2011, 7, 1130–1134, doi:10.3762/bjoc.7.130

• , Scheme S1). Briefly, compound 3 can be obtained through polymer-analogous amidation with 5-hexynoic acid and subsequent reaction with mono-(6-azido-6-desoxy)-β-cyclodextrin by click reaction under microwave assisted conditions. Synthesis of 1,4-di-N-adamantylaminoanthraquinone (2): 2 was synthesized

Novel synthesis of pseudopeptides bearing a difluoromethyl group by Ugi reaction and desulfanylation

• Jingjing Wu,
• Hui Li and
• Song Cao

Beilstein J. Org. Chem. 2011, 7, 1070–1074, doi:10.3762/bjoc.7.123

• ][30]. Recently, we reported a novel and general strategy for the construction of a difluoromethyl compound library, and we further illustrated this strategy by application to the synthesis of CF2H-bearing pseudopeptides and 1,2,3-triazoles through Ugi and click reaction, respectively [27][30]. In

Calix[4]arene-click-cyclodextrin and supramolecular structures with watersoluble NIPAAM-copolymers bearing adamantyl units: “Rings on ring on chain”

• Bernd Garska,
• Monir Tabatabai and
• Helmut Ritter

Beilstein J. Org. Chem. 2010, 6, 784–788, doi:10.3762/bjoc.6.83

• Bernd Garska Monir Tabatabai Helmut Ritter Institut für Organische Chemie und Makromolekulare Chemie, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf, Germany 10.3762/bjoc.6.83 Abstract We describe the calixarene-cyclodextrin-coupling via click reaction starting from

• of guest molecules are of increasing practical and theoretical interest [1][2][3]. In this context, we recently coupled cyclodextrin (CD) with cucubituril via a click reaction and investigated the special interactions with some suitable copolymers [4]. Because of their capability to form host–guest

• calixarenes and β-CD via click reaction and their application in the field of supramolecular chemistry has not yet been reported. Herein, we describe the synthesis and complexation behavior of a dual type calix[4]arene-click-cyclodextrin (4) receptor by the cycloaddition of a dipropargylether of calix[4]arene

New amphiphilic glycopolymers by click functionalization of random copolymers – application to the colloidal stabilisation of polymer nanoparticles and their interaction with concanavalin A lectin

• Otman Otman,
• Paul Boullanger,
• Eric Drockenmuller and
• Thierry Hamaide

Beilstein J. Org. Chem. 2010, 6, No. 58, doi:10.3762/bjoc.6.58

• alcoholic media and water. In our case, the click reaction was performed with CuSO4 and sodium ascorbate in a THF/water mixture (Figure 2). This approach was preferred to the use of other catalysts because of the applications listed in the specific area of colloidal stabilization and the ease of removal of

Bioorthogonal metabolic glycoengineering of human larynx carcinoma (HEp-2) cells targeting sialic acid

• Arne Homann,
• Riaz-ul Qamar,
• Sevnur Serim,
• Petra Dersch and
• Jürgen Seibel

Beilstein J. Org. Chem. 2010, 6, No. 24, doi:10.3762/bjoc.6.24

• reaction was performed according to a modified protocol of the [3+2] triazole cycloaddition [15][16]. The appropriate functionalized fluorescent detection molecule and the conditions for the click reaction (CuSO4, sodium ascorbate and tris[(1-benzyl-1H-1,2,3-triazol-4-yl)methyl]amine, TBTA) were applied in

• surface presentation of Ac4GlcNAc 16 as well as the new substrate Neu5Hex 3 was successful. The copper-catalyzed [3+2] triazole formation (“click reaction”) proved very useful for the cell surface labelling because of its bioorthogonality. The incubation of HEp-2 cells with the sialic acid analogue

• drawback of the reaction parameters and compounds used for the click reaction is the cytotoxicity of DMSO and copper. But this problem for in vivo labelling can be overcome by different reaction conditions and different detection molecules. For example, the strain-promoted click reaction with difluorinated

Dimerization of propargyl and homopropargyl 6-azido- 6-deoxy- glycosides upon 1,3-dipolar cycloaddition

• Nikolas Pietrzik,
• Daniel Schmollinger and
• Thomas Ziegler

Beilstein J. Org. Chem. 2008, 4, No. 30, doi:10.3762/bjoc.4.30

• Nikolas Pietrzik Daniel Schmollinger Thomas Ziegler Institute of Organic Chemistry, University of Tuebingen, Auf der Morgenstelle 18, 72076 Tuebingen, Germany. 10.3762/bjoc.4.30 Abstract Copper-catalyzed, thermal or microwave promoted 1,3-dipolar cycloaddition (Click Reaction) of 2-propynyl and 3

• -butynyl 2,3,4-tri-O-acetyl-6-azido-6-deoxy-glycopyranosides in the D-gluco, D-galacto and D-manno series afford the corresponding dimeric cycloaddition products. Keywords: click reaction; cyclodimerization; glycosides; triazoles; Introduction Our ongoing interest in constructing combinatorial libraries

• -triazoles which are known to be easily generated through a copper-catalyzed 1,3-dipolar cycloaddition of an organic azide and an alkynyl derivative (Click Reaction) [5][6][7]. For review articles on copper-catalyzed Click Reactions see references [8][9][10][11]. Recently, we applied this approach to a