Orthogonal photoswitching of heterobivalent azobenzene glycoclusters: the effect of glycoligand orientation in bacterial adhesion

• Leon M. Friedrich and
• Thisbe K. Lindhorst

Beilstein J. Org. Chem. 2025, 21, 736–748, doi:10.3762/bjoc.21.57

• - and heteromultivalency effects are crucial [8][9][10][11][12], but also many other aspects of glycoligand presentation govern carbohydrate recognition. Interestingly, even a subtle structural variation in heterobivalent glycoclusters can result in unexpected differences in lectin binding due to

• thiomannopyranoside 10 yielded the protected glycocluster 12 in 60% yield. A subsequent Zemplén deacetylation gave the homobivalent glycocluster 6αMan3αMan 2 in quantitative yield (Scheme 1). In order to synthesize the glycoazobenzene antennas contained in the glycoclusters 1 and 2, the β-ᴅ-glucopyranosyloxy- and the

• Table 1 shows that the PSS values of the bis-azobenzene glycoclusters 1 and 2 are in a similar range. Furthermore, the glycoazobenzene antennas comprised in 1 and 2 show a similar switching behavior as the individual antennas 6αMan 3, 6βGlc 4, and 3αMan 5. Wavelength-selective photoswitching of 2 as

Pathoblockers or antivirulence drugs as a new option for the treatment of bacterial infections

• Matthew B. Calvert,
• Varsha R. Jumde and
• Alexander Titz

Beilstein J. Org. Chem. 2018, 14, 2607–2617, doi:10.3762/bjoc.14.239

• . Therefore, multivalent display of lectin and ligand results in a higher avidity [22][23]. The Lindhorst group also synthesized and analyzed so-called glycoclusters, e.g., 7 (Figure 1), where the saccharide moiety is displayed in a multivalent fashion [17][24][25][26]. When this simple trimannosylated

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

• comparison to other glycoclusters, i.e., glycolipid micelles and glycoproteins, which allows an ordered, controlled and stable tridimensional presentation of the ligands, providing higher ligand binding capacity [6][96]. For this reason, they represent an ideal scaffold to study the activation of the immune

Synthesis of divalent ligands of β-thio- and β-N-galactopyranosides and related lactosides and their evaluation as substrates and inhibitors of Trypanosoma cruzi trans-sialidase

• María Emilia Cano,
• Rosalía Agusti,
• Alejandro J. Cagnoni,
• María Florencia Tesoriero,
• José Kovensky,
• María Laura Uhrig and
• Rosa M. de Lederkremer

Beilstein J. Org. Chem. 2014, 10, 3073–3086, doi:10.3762/bjoc.10.324

• terminal units and it has been demonstrated that it plays an important role in the infection. Herein, the enzyme was also tested as a tool for the chemoenzymatic synthesis of sialic acid containing glycoclusters. The transfer reaction of sialic acid was performed using a recombinant TcTS and 3

• , lactitol efficiently controlled the apoptosis triggered by TcTS [23]. The synthesis of multivalent glycoclusters designed to be high affinity ligands for specific proteins has been an active area of research during the last years [24][25][26][27][28]. Among them, tetravalent glycoclusters bearing β

• disialylated glycoclusters obtained (mainly in the case of 18, and also for 16, although at a lesser extent) is related to the structure of the acceptor and the experimental conditions. When both arms of the divalent precursors are sufficiently distant one from the other, they may be independently available

Expeditive synthesis of trithiotriazine-cored glycoclusters and inhibition of Pseudomonas aeruginosa biofilm formation

• Meriem Smadhi,
• Sophie de Bentzmann,
• Anne Imberty,
• Marc Gingras,
• Raoudha Abderrahim and
• Peter G. Goekjian

Beilstein J. Org. Chem. 2014, 10, 1981–1990, doi:10.3762/bjoc.10.206

• glycoclusters based on a triazine core bearing D-galactose and L-fucose epitopes are able to inhibit biofilm formation by Pseudomonas aeruginosa. These multivalent ligands are simple to synthesize, are highly soluble, and can be either homofunctional or heterofunctional. The galactose-decorated cluster shows

• lectins in the form of glycoclusters [17], poly(glycomer)s [18][19][20][21], and glycodendrimers [22][23][24]. In regards to PA, C-fucosylpeptide dendrimers were shown to inhibit biofilm formation and to efficiently disperse established biofilms in both reference and hospital strains of PA [25][26][27

• electrochemical properties [34] (Figure 1). They were also highly potent lectin aggregators. Among other aromatic glycoasterisks, Roy et al. described the synthesis of densely substituted hexaphenylbenzene glycoclusters [35]. In this work, we have designed a new family of low-valent glycoclusters based on a

Convergent synthetic methodology for the construction of self-adjuvanting lipopeptide vaccines using a novel carbohydrate scaffold

• Vincent Fagan,
• Istvan Toth and
• Pavla Simerska

Beilstein J. Org. Chem. 2014, 10, 1741–1748, doi:10.3762/bjoc.10.181

• gave the novel carbohydrate building block 1 in 31% overall yield (Scheme 2). Similar carbohydrates have been used for the preparation of glycoclusters for lectin binding [25][26][27][28] and as scaffold carriers of multiple peptide antigens [17][29]. However, the synthesis of the new carbohydrate

Clicked and long spaced galactosyl- and lactosylcalix[4]arenes: new multivalent galectin-3 ligands

• Silvia Bernardi,
• Paola Fezzardi,
• Gabriele Rispoli,
• Stefania E. Sestito,
• Francesco Peri,
• Francesco Sansone and
• Alessandro Casnati

Beilstein J. Org. Chem. 2014, 10, 1672–1680, doi:10.3762/bjoc.10.175

• Milano-Bicocca, Piazza della Scienza 2, 20126 Milano, Italy 10.3762/bjoc.10.175 Abstract Four novel calix[4]arene-based glycoclusters were synthesized by conjugating the saccharide units to the macrocyclic scaffold using the CuAAC reaction and using long and hydrophilic ethylene glycol spacers

Synthesis and solvodynamic diameter measurements of closely related mannodendrimers for the study of multivalent carbohydrate–protein interactions

• Yoann M. Chabre,
• Alex Papadopoulos,
• Alexandre A. Arnold and
• René Roy

Beilstein J. Org. Chem. 2014, 10, 1524–1535, doi:10.3762/bjoc.10.157

• , compared to the one generated in BTAs-centered structures 12 and 21, could explain this observation. Also, these discrepancies might result from the general amphiphilic behavior of this kind of macromolecules [39]. In fact, these glycoclusters shared common structural factors with hydrophilic peripheral

• mannosylated glycoclusters and glycodendrimers were efficiently accomplished around a benzene core and using the CuAAc methods now routinely used in this field [9][41][42]. The targeted compounds were based on trimesic acid scaffold which is known to properly expose the surface sugar groups to tetrameric

• of glycoclusters. Experimental General remarks All reactions in organic medium were performed in standard oven-dried glassware under an inert atmosphere of nitrogen using freshly distilled solvents. CH2Cl2 was distilled from CaH2 and DMF from ninhydrin, and kept over molecular sieves. Solvents and

A new synthetic access to 2-N-(glycosyl)thiosemicarbazides from 3-N-(glycosyl)oxadiazolinethiones and the regioselectivity of the glycosylation of their oxadiazolinethione precursors

• El Sayed H. El Ashry,
• El Sayed H. El Tamany,
• Mohy El Din Abdel Fattah,
• Mohamed R. E. Aly,
• Ahmed T. A. Boraei and
• Axel Duerkop

Beilstein J. Org. Chem. 2013, 9, 135–146, doi:10.3762/bjoc.9.16

• ]. Glycosylamines are used also as enzyme inhibitors and vaccine precursors [18][19][20][21], and in glycopeptide synthesis [22][23] and in glycodendrimers and glycoclusters [24][25]. There are four structural isomers of glycosyl-thiosemicarbazides according to the location of the glycosyl residue on the

S-Fluorenylmethyl protection of the cysteine side chain upon N^α-Fmoc deprotection

• Johannes W. Wehner and
• Thisbe K. Lindhorst

Beilstein J. Org. Chem. 2012, 8, 2149–2155, doi:10.3762/bjoc.8.242

• transprotection reaction was studied. Keywords: Fmoc protecting group; glycoamino acids; N-Fmoc→S-Fm transprotection; protecting groups; Introduction In the course of our work on the synthesis of glycoamino acids, we have recently used L-cysteine as a scaffold for the synthesis of various glycoclusters [1][2][3

• different basic reaction conditions. Though this type of transprotection reaction has been described before, here the first example with glycoamino acid derivatives is reported. The results of our study can be utilized wherever glycocysteine derivatives are employed in the synthesis of glycoclusters or

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

• variety of useful conjugation reactions, including mono- as well as oligo- and polyvalent amines, and the carbohydrate decoration of functionalized surfaces. Fields of application concern the construction of oligovalent glycoconjugates, such as glycoclusters and glycodendrimers, the modification of

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

• conveniently prepared by employing a one-pot procedure for Cu(II)-catalyzed diazo transfer and Cu(I)-catalyzed azide–alkyne cycloaddition (CuAAC) starting from commercially available amines. These glycoclusters were probed for their binding potencies to the plant lectin wheat germ agglutinin (WGA) from

• explanation for the observed binding affinities. Results and Discussion Synthesis of glycoclusters The Cu(I)-catalyzed [49][50] Huisgen [3 + 2] cycloaddition [51] of azides and alkynes (CuAAC) is a frequently used method for the covalent attachment of carbohydrate epitopes to azide- or alkyne-presenting

• scaffolds [52][53][54]. Recently, we reported a convenient one-pot procedure for diazo transfer and azide–alkyne cycloaddition [48] giving access to multivalent triazole-linked structures starting from amines. For the synthesis of triazole-linked glycoclusters, commercially available amines A1–A6 (Figure 1

Synthetic glycopeptides and glycoproteins with applications in biological research

• Ulrika Westerlind

Beilstein J. Org. Chem. 2012, 8, 804–818, doi:10.3762/bjoc.8.90

• and lectin binding [95][96][97][98][99][100][101][102][103][104][105]. The synthesis of glycoclusters/dendrimers is an area of research aimed at tackling the increasing problems with bacterial multi-antibiotic resistance. Microbe adherence to the glycans on the tissue cell surface is essential for an

• microbe and lectin binding studies, glycopeptide based glycoclusters/dendrimers were applied, employing linear peptide backbones, cyclic peptide scaffolds or multi-lysine scaffolds [106][107][108][109][110][111][112][113][114][115][116][117][118]. The pentavalent cholera toxin protein secreted by Vibrio

Synthesis of heteroglycoclusters by using orthogonal chemoselective ligations

• Baptiste Thomas,
• Michele Fiore,
• Isabelle Bossu,
• Pascal Dumy and
• Olivier Renaudet

Beilstein J. Org. Chem. 2012, 8, 421–427, doi:10.3762/bjoc.8.47

• metastasis [1]. Synthetic molecules displaying multiple copies of a sugar binding motif, called (homo)glycoclusters, represent attractive tools for studying these complex recognition processes as well as for developing biological applications, for example, the inhibition of infections by pathogens such as

• glycoclusters active at nanomolar concentration [8][9][10], the achievement of selective binding remains challenging because of the close structural similarities of the binding sites of proteins specific for the same carbohydrate moiety. Interestingly, recent reports have highlighted that the association of

• tetravalent cyclopeptide sequence, whereas the second series (heteroglycocluster 3:1) contains one of a given sugar and three of another. Results and Discussion Glycoclusters are classically constructed from a molecular scaffold containing multiple anchoring sites that can be functionalized with sugars by

(Pseudo)amide-linked oligosaccharide mimetics: molecular recognition and supramolecular properties

• José L. Jiménez Blanco,
• Fernando Ortega-Caballero,
• Carmen Ortiz Mellet and
• José M. García Fernández

Beilstein J. Org. Chem. 2010, 6, No. 20, doi:10.3762/bjoc.6.20

• thiourea, urea and guanidine. In this review we summarise the advances over the last decade in the synthesis of oligosaccharide mimetics that possess amide and pseudoamide linkages, as well as studies focussing on their supramolecular and recognition properties. Keywords: carbopeptoids; glycoclusters