A stereoselective and flexible synthesis to access both enantiomers of N-acetylgalactosamine and peracetylated N-acetylidosamine

• Bettina Riedl and
• Walther Schmid

Beilstein J. Org. Chem. 2018, 14, 856–860, doi:10.3762/bjoc.14.71

• : asymmetric synthesis; carbohydrates; N-acetylgalactosamine; N-acetylidosamine; Introduction N-Acetylgalactosamine (GalNAc, Figure 1) and N-acetylidosamine (IdoNAc) belong to the group of 2-amino-2-deoxysugars, which can be found in a wide range of organisms as building blocks of, e.g., glycosaminoglycans

Synthesis of a sucrose-based macrocycle with unsymmetrical monosaccharides "arms"

• Karolina Tiara,
• Mykhaylo A. Potopnyk and
• Sławomir Jarosz

Beilstein J. Org. Chem. 2018, 14, 634–641, doi:10.3762/bjoc.14.50

• ; Introduction Chiral macrocyclic compounds play an important role in supramolecular and biological systems [1][2]. Many of them serve as convenient receptors for cations [3], anions [4], ion pairs [5], neutral molecules [6] etc. Binaphthols [7][8][9], amino acids [10], chiral diamines [11][12], carbohydrates

Carbohydrate inhibitors of cholera toxin

• Vajinder Kumar and
• W. Bruce Turnbull

Beilstein J. Org. Chem. 2018, 14, 484–498, doi:10.3762/bjoc.14.34

• released by Vibrio cholera in the host’s intestine. The toxin enters intestinal epithelial cells after binding to specific carbohydrates on the cell surface. Over recent years, considerable effort has been invested in developing inhibitors of toxin adhesion that mimic the carbohydrate ligand, with

Recent applications of click chemistry for the functionalization of gold nanoparticles and their conversion to glyco-gold nanoparticles

• Vivek Poonthiyil,
• Thisbe K. Lindhorst,
• Vladimir B. Golovko and
• Antony J. Fairbanks

Beilstein J. Org. Chem. 2018, 14, 11–24, doi:10.3762/bjoc.14.2

• combination of a gold nanoparticle core and an outer-shell comprising multivalent presentation of carbohydrates. The combination of the distinctive physicochemical properties of the gold core and the biological function/activity of the carbohydrates makes glyco-gold nanoparticles a valuable tool in

• glycoscience. In this review we present recent advances made in the use of one type of click chemistry, namely the azide–alkyne Huisgen cycloaddition, for the functionalization of gold nanoparticles and their conversion to glyco-gold nanoparticles. Keywords: azide–alkyne Huisgen cycloaddition; carbohydrates

• 21st century [1]. Gold nanoparticles (AuNPs) are one of the most significant and stable classes of metal NPs [2] and have potential applications in optics [3], biology [4] and catalysis [5]. Carbohydrates are one of the classes of molecules that are essential for life. Although they are involved in

An efficient synthesis of 1,6-anhydro-N-acetylmuramic acid from N-acetylglucosamine

• Matthew B. Calvert,
• Christoph Mayer and
• Alexander Titz

Beilstein J. Org. Chem. 2017, 13, 2631–2636, doi:10.3762/bjoc.13.261

• Matthew B. Calvert Christoph Mayer Alexander Titz Chemical Biology of Carbohydrates, Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), D-66123 Saarbrücken, Germany Deutsches Zentrum für Infektionsforschung (DZIF), Standort Hannover-Braunschweig, Germany Interfaculty Institute of

What contributes to an effective mannose recognition domain?

• Christoph P. Sager,
• Deniz Eriş,
• Martin Smieško,
• Rachel Hevey and
• Beat Ernst

Beilstein J. Org. Chem. 2017, 13, 2584–2595, doi:10.3762/bjoc.13.255

• generally weak interactions of carbohydrates that bind on the solvent exposed surface of proteins, as compared to those of the majority of marketed drugs that most frequently bind to protein cavities. Additionally, buried and less solvent exposed ligands show slower exchange rates, characterized by a high

• overall desolvation penalty is slightly reduced resulting in an overall desolvation cost of ΔG = 34 kJ/mol for both hydroxy groups (Figure 4B). Since carbohydrates in general exhibit a number of adjacent hydroxy groups, their desolvation penalties are difficult to assess but it is most likely that each

An efficient synthesis of a C₁₂-higher sugar aminoalditol

• Łukasz Szyszka,
• Anna Osuch-Kwiatkowska,
• Mykhaylo A. Potopnyk and
• Sławomir Jarosz

Beilstein J. Org. Chem. 2017, 13, 2146–2152, doi:10.3762/bjoc.13.213

• : higher carbon sugars; reductive amination; sucrose; Introduction Carbohydrates, because of their availability in a variety of optical pure forms, are particularly useful in planning and executing the synthesis of chiral macrocyclic compounds [1][2][3][4][5]. In this context, polyhydroxylated derivatives

Solid-state studies and antioxidant properties of the γ-cyclodextrin·fisetin inclusion compound

• Joana M. Pais,
• Maria João Barroca,
• Maria Paula M. Marques,
• Filipe A. Almeida Paz and
• Susana S. Braga

Beilstein J. Org. Chem. 2017, 13, 2138–2145, doi:10.3762/bjoc.13.212

• , the step associated with the decomposition of fisetin (which should be visible after 310 °C) is missing. Such effect may arise from the thermal protection properties of the cyclodextrin, since these cyclic carbohydrates are known to act as flame retardants [39]. The same effect is also observed in the

Preactivation-based chemoselective glycosylations: A powerful strategy for oligosaccharide assembly

• Weizhun Yang,
• Bo Yang,
• Sherif Ramadan and
• Xuefei Huang

Beilstein J. Org. Chem. 2017, 13, 2094–2114, doi:10.3762/bjoc.13.207

• ; Review Introduction Carbohydrates are widely present in nature and many of them are involved in important physiological and pathological events, such as anticoagulation, inflammation and pathogen infection [1][2]. In order to explore their biological functions, oligosaccharides with high purity are

Intramolecular glycosylation

• Xiao G. Jia and
• Alexei V. Demchenko

Beilstein J. Org. Chem. 2017, 13, 2028–2048, doi:10.3762/bjoc.13.201

• glycosylation reactions wherein the facial stereoselectivity is achieved by tethering of the glycosyl donor and acceptor counterparts. Keywords: carbohydrates; glycosylation; intramolecular reactions; oligosaccharides; Introduction With recent advances in glycomics [1][2], we now know that half of the

• branching patterns, can indicate the presence and progression of a disease [5][6][7][8][9]. With a better understanding of functions of carbohydrates, the quest for reliable synthetic methods has launched, thus elevating the priority for improving our synthetic competences. The development of new methods

New bio-nanocomposites based on iron oxides and polysaccharides applied to oxidation and alkylation reactions

• Daily Rodríguez-Padrón,
• Alina M. Balu,
• Antonio A. Romero and
• Rafael Luque

Beilstein J. Org. Chem. 2017, 13, 1982–1993, doi:10.3762/bjoc.13.194

• been an attractive option to imitate based on a fundamental and rational understanding [28][32]. In that sense, polysaccharides extracted from fungal organisms can be used both as nanoparticle carriers and sacrificial templates due to their highly functionalized structure. Although such carbohydrates

Influence of the milling parameters on the nucleophilic substitution reaction of activated β-cyclodextrins

• László Jicsinszky,
• Kata Tuza,
• Giancarlo Cravotto,
• Andrea Porcheddu,
• Francesco Delogu and
• Evelina Colacino

Beilstein J. Org. Chem. 2017, 13, 1893–1899, doi:10.3762/bjoc.13.184

• effect on the nucleophilic reaction. Keywords: cyclodextrins; milling parameters; nucleophilic substitution; planetary ball mill; Introduction Their hollow structures make cyclodextrins (CDs) a class of carbohydrates that can form inclusion complexes with organic molecules, inorganic salts and complex

Enzymatic synthesis of glycosides: from natural O- and N-glycosides to rare C- and S-glycosides

• Jihen Ati,
• Pierre Lafite and
• Richard Daniellou

Beilstein J. Org. Chem. 2017, 13, 1857–1865, doi:10.3762/bjoc.13.180

• published roadmap for glycosciences in Europe, carbohydrates are expected, both by academics and industrials, to become key players in a near future in tremendous fields such as pharmaceuticals and personalized biomedicine, food, materials and renewable resources, and bioenergy for examples [2]. To achieve

• retaining mechanism). In the case of O-GTs, the nucleophile is an alcohol or a phenol (carbohydrates, serine, threonine, …), whereas in N-GTs, the nature of the nitrogen-containing group is more diverse (amines, amides, guanidine or even indoles) [12]. S- and C-GTs follow a similar mechanism with the

• ][25], and thurandacin [26] revealed S-glycosylation of cysteines. Carbohydrates bound to these bacteriocins are glucose or N-acetylglucosamine. For two of these glycopeptides, the corresponding S-GTs have been characterized and their versatility for a wide range of sugar donors has been tested [26][27

Molecular recognition of N-acetyltryptophan enantiomers by β-cyclodextrin

• Spyros D. Chatziefthimiou,
• Mario Inclán,
• Petros Giastas,
• Athanasios Papakyriakou,
• Konstantina Yannakopoulou and
• Irene M. Mavridis

Beilstein J. Org. Chem. 2017, 13, 1572–1582, doi:10.3762/bjoc.13.157

• structure; Introduction Cyclodextrins (CDs) are cyclic, water-soluble carbohydrates with a rather non-polar cavity that can host a variety of organic molecules (guests) and form inclusion complexes [1]. The guest molecules may be completely or partly enclosed inside the cavity depending on their size and

Strategies toward protecting group-free glycosylation through selective activation of the anomeric center

• A. Michael Downey and
• Michal Hocek

Beilstein J. Org. Chem. 2017, 13, 1239–1279, doi:10.3762/bjoc.13.123

• unactivated carbohydrates to form glycoconjugates. Furthermore, this reaction operates under neutral conditions further increasing its power and potential for widespread application in protecting-group-free glycosylations. However, there are mainly two obvious drawbacks of the operation: First, the formation

Aqueous semisynthesis of C-glycoside glycamines from agarose

• Juliana C. Cunico Dallagnol,
• Alexandre Orsato,
• Diogo R. B. Ducatti,
• Miguel D. Noseda,
• Maria Eugênia R. Duarte and
• Alan G. Gonçalves

Beilstein J. Org. Chem. 2017, 13, 1222–1229, doi:10.3762/bjoc.13.121

• , methyl- or dimethylamine, and the use of a diluted basic (pH 11) reaction media were identified as important aspects to achieve improved yields, as well as to decrease the amount of byproducts commonly related to reductive amination of carbohydrates. This strategy allowed the transposition of the 3,6

• an aldehyde hydrate moiety associated to free AnGal, such a strategy could be conducted through reductive amination reactions. Even though reductive amination has been widely used in organic synthesis, its applicability remains challenging when dealing with carbohydrates [18][19][20]. Rearrangements

• obtain C-glycofuranose-containing glycamines through a short, protecting-group-free and aqueous-based semisynthesis. Our present study also addressed the obstacles frequently faced in reductive amination of carbohydrates (such as byproduct accumulation and purification issues) and contributed to provide

Sugar-based micro/mesoporous hypercross-linked polymers with in situ embedded silver nanoparticles for catalytic reduction

• Qing Yin,
• Qi Chen,
• Li-Can Lu and
• Bao-Hang Han

Beilstein J. Org. Chem. 2017, 13, 1212–1221, doi:10.3762/bjoc.13.120

• microporous HCPs based on carbohydrates for carbon dioxide capture and storage by hydrogen bonding and dipole–quadrupole interactions [17]. The reported pore-size distribution (PSD) and related porosity tuning are in the range of micropore size. Considering that the polyhydroxylated and chiral structure

• obtained by a similar method based on carbohydrates reported by Liu and Dai [17], our obtained porous polymers not only exhibit micro/mesoporous features, but can also be modified and functionalized for further applications. The porous organic polymer SugPOP-1 containing an aldehyde functionality can be

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

• 1930, the first crystal structures of organic compounds to be investigated were carbohydrates of low molecular weight. Over the following years, only eight additional crystal structures were reported. The determination of the three dimensional structure of the dehydrated form of sucrose, in 1947, was

• few thousand entries for carbohydrate crystal structures, among which a limited number of molecules are relevant to glycobiology. With the exception of sucrose and cyclic compounds, such as cyclodextrins or cyclo-amyloses, carbohydrates are reluctant to crystallize in form and size suitable for X-ray

• the biosynthesis of glycosidic linkage requires the transfer of a sugar residue from a donor to an acceptor [35]. Acceptor substrates are carbohydrates, proteins, lipids, DNA, flavonol, antibiotics and steroids. In contrast, glycosyl donor substrates are mostly sugar nucleotides, such as UDP-GlcNAc

An eco-compatible strategy for the diversity-oriented synthesis of macrocycles exploiting carbohydrate-derived building blocks

• Sushil K. Maurya and
• Rohit Rana

Beilstein J. Org. Chem. 2017, 13, 1106–1118, doi:10.3762/bjoc.13.110

• ] glycosides and macrocyclic glycolipids [11]. Similarly, the copper-catalyzed azide–alkyne cycloaddition (CuAAC) reaction has found wide application in medicinal chemistry [33], biology [34][35], polymer chemistry [36], carbohydrates [37][38][39][40], peptides [41][42][43][44] and in materials science [45][46

• domain shuffling has been used for the synthesis of small molecules and macrocyclic libraries. Further, several DOS strategies based around build/couple/pair (B/C/P) were developed for the synthesis of compound libraries including macrocycles [18][55]. Carbohydrates as building blocks are inexpensive and

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

• , Nanotechnology Lab., Via G. Fantoli 16/15, 20138 Milan, Italy 10.3762/bjoc.13.100 Abstract Glyco-gold nanoparticles combine in a single entity the peculiar properties of gold nanoparticles with the biological activity of carbohydrates. The result is an exciting nanosystem, able to mimic the natural multivalent

• : gold nanoparticles; glyco nanoparticles; glyconanomaterials; immunology; targeting; Introduction Carbohydrates are well recognized as crucial biomolecules for their capability to produce an enormous number of biocodes which are translated into their ability to promote or suppress a plethora of

• biological events [1]. Nevertheless, carbohydrates interact with their ligands in a very weak manner, so much faint that nature found in the multi-presentation (the so called “glycocalix”) a solution to have efficient carbohydrate interactions. In fact, the sum of binding affinities for single and isolated

Fluorescent carbon dots from mono- and polysaccharides: synthesis, properties and applications

• Stephen Hill and
• M. Carmen Galan

Beilstein J. Org. Chem. 2017, 13, 675–693, doi:10.3762/bjoc.13.67

• traditional semiconductor quantum dots (QDs). Particularly in the areas of live imaging and drug delivery, due to their water solubility, low toxicity and photo- and chemical stability. Carbohydrates are readily available chiral biomolecules in nature which offer an attractive and cheap starting material from

• ., graphite or graphene. Conversely bottom-up methodologies rely on the use of a molecular precursor which can be treated in such a way as to seed the formation of a CD. Typical starting materials include amino acids, citric acid, biomass and carbohydrates to name but a few, which can be reacted using thermal

• . Resultantly, differential properties are easily acquired through minor manipulations of the CD synthesis. To date, the de novo rational design of bottom-up syntheses of CDs for advanced application is limited in the literature. Carbohydrates are one of the most diverse and important class of biomolecules in

Exploring endoperoxides as a new entry for the synthesis of branched azasugars

• Svenja Domeyer,
• Mark Bjerregaard,
• Henrik Johansson and
• Daniel Sejer Pedersen

Beilstein J. Org. Chem. 2017, 13, 644–647, doi:10.3762/bjoc.13.63

• these building blocks provided access to a variety of derivatives including tetrahydrofurans, epoxides and protected amino-tetraols. Keywords: azasugar; carbohydrate; cycloaddition; endoperoxide; photochemistry; Introduction Azasugars are small organic compounds that can mimic carbohydrates or their

• strategies have since been developed, including asymmetric and chemoenzymatic methods [2][6][7][8]. Substituted endoperoxides have been applied to the synthesis of substituted cyclopropanes, furans and carbohydrates [9][10][11][12]. Inspired by the work of Robinson and co-workers [10][11][12] we hypothesised

Adsorption of RNA on mineral surfaces and mineral precipitates

• Elisa Biondi,
• Yoshihiro Furukawa,
• Jun Kawai and
• Steven A. Benner

Beilstein J. Org. Chem. 2017, 13, 393–404, doi:10.3762/bjoc.13.42

• roles. (iii) As inhibitors of reactions. One key problem obstructing the assembly of prebiotically productive organic species is the well-known propensity of organic molecules, especially those containing carbonyl groups such as carbohydrates, to react further to yield unproductive "tars". Mineral

O-Alkylated heavy atom carbohydrate probes for protein X-ray crystallography: Studies towards the synthesis of methyl 2-O-methyl-L-selenofucopyranoside

• Roman Sommer,
• Dirk Hauck,
• Annabelle Varrot,
• Anne Imberty,
• Markus Künzler and
• Alexander Titz

Beilstein J. Org. Chem. 2016, 12, 2828–2833, doi:10.3762/bjoc.12.282

• Roman Sommer Dirk Hauck Annabelle Varrot Anne Imberty Markus Kunzler Alexander Titz Chemical Biology of Carbohydrates, Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), D-66123 Saarbrücken, Germany Deutsches Zentrum für Infektionsforschung (DZIF), Standort Hannover-Braunschweig

• -methylated carbohydrate ligands was demonstrated (e.g., 2, Figure 1). O-Methylation of carbohydrates is a rare modification, but widespread in nature as it has been observed in bacteria, protozoa, animals and plants but not in mammals [29][30]. Besides fungal and animal tectonins that recognize O-methylated

Orthogonal protection of saccharide polyols through solvent-free one-pot sequences based on regioselective silylations

• Serena Traboni,
• Emiliano Bedini and
• Alfonso Iadonisi

Beilstein J. Org. Chem. 2016, 12, 2748–2756, doi:10.3762/bjoc.12.271

• experimentally simple tool for the straightforward access to saccharide building-blocks useful in organic synthesis. Keywords: carbohydrates; one-pot synthesis; regioselective protection; silyl protecting group; solvent-free reaction; Introduction The application of an orthogonal set of protecting groups

• represents a typical issue in organic synthesis in the elaboration of highly functionalized molecules such as carbohydrates, and lengthy multistep procedures are often needed to this aim [1][2]. Silyl groups are widely applied in organic chemistry in orthogonal protection strategies owing to their stability

• synthesis of per-O-trimethylsilylated derivatives (Scheme 1), widely used precursors in one-pot strategies for orthogonal protection of carbohydrates [62][63][64][65][66][67]. Application of the TBAB-catalyzed protocol on glucoside 3 gave product 26 in high yield within a few minutes (Scheme 1, reaction 1