The B & B approach: Ball-milling conjugation of dextran with phenylboronic acid (PBA)-functionalized BODIPY

• Patrizia Andreozzi,
• Lorenza Tamberi,
• Elisamaria Tasca,
• Gina Elena Giacomazzo,
• Marta Martinez,
• Mirko Severi,
• Marco Marradi,
• Stefano Cicchi,
• Sergio Moya,
• Giacomo Biagiotti and
• Barbara Richichi

Beilstein J. Org. Chem. 2020, 16, 2272–2281, doi:10.3762/bjoc.16.188

• the mechanochemical approach (the B & B, ball milling for boronic acid conjugation) as bioconjugation strategy for the labeling of biocompatible carbohydrates. Fluorescent labeling is of key importance to follow up the fate of molecules and (nano)materials inside cells and in the human body. In this

How and why plants and human N-glycans are different: Insight from molecular dynamics into the “glycoblocks” architecture of complex carbohydrates

• Carl A. Fogarty,
• Aoife M. Harbison,
• Amy R. Dugdale and
• Elisa Fadda

Beilstein J. Org. Chem. 2020, 16, 2046–2056, doi:10.3762/bjoc.16.171

• relationships in complex carbohydrates, with important implications in glycoengineering design. Keywords: complex carbohydrates; fucose; glycoblocks; molecular dynamics; molecular recognition; N-glycans; xylose; Introduction Complex carbohydrates (or glycans) are an essential class of biomolecules, directly

• invoked when discussing other biopolymers or complex carbohydrates. In the specific case of glycans, the structural complexity, in terms of the diversity of monosaccharides, the linkages’ stereochemistry and the branched scaffolds, makes the already difficult case even more intricate. Nevertheless, the

• ultimately understand more clearly the relationships between sequence and structure in complex carbohydrates. Representative structures of the plant N-glycans studied in this work with corresponding nomenclature. The letters f, x, and g indicate the presence of Fuc, Xyl and β(1-3) Gal, respectively, and ng

Nonenzymatic synthesis of anomerically pure, mannosyl-based molecular probes for scramblase identification studies

• Giovanni Picca,
• Markus Probst,
• Simon M. Langenegger,
• Oleg Khorev,
• Peter Bütikofer,
• Anant K. Menon and
• Robert Häner

Beilstein J. Org. Chem. 2020, 16, 1732–1739, doi:10.3762/bjoc.16.145

• citronellol derivative via a phosphodiester bridge. Moreover, a novel phosphoramidite chemistry-based method offers a straightforward approach for the non-enzymatic incorporation of the saccharide moiety in an anomerically pure form. Keywords: carbohydrates; citronellol; phosphoramidite; photoclickable

• . Reports of using phosphoramidite chemistry for the preparation of carbohydrates via the anomeric position are relatively rare [18][19][20][21][22][23]. Alternatively, the H-phosphonate approach has been used to convert carbohydrates into phosphate-linked derivatives at the anomeric center [24][25][26][27

Synthesis of new asparagine-based glycopeptides for future scanning tunneling microscopy investigations

• Laura Sršan and
• Thomas Ziegler

Beilstein J. Org. Chem. 2020, 16, 888–894, doi:10.3762/bjoc.16.80

• cell surfaces for future investigations by combined preparative mass spectroscopy and scanning tunneling microscopy (STM) using soft-landing electrospray beam deposition (ES-IBD), on metal surfaces. Keywords: amino acids; asparagine; carbohydrates; glycopeptides; peptidomimetics; Introduction

• comparison with naturally occurring amino acids [14]. Thus, there is still a great effort in finding new potential drugs derived from glycopeptides [4][15]. By using preparative mass spectrometry (pMS) combined with STM on submolecular-resolution peptides and carbohydrates can be investigated regarding their

Extension of the 5-alkynyluridine side chain via C–C-bond formation in modified organometallic nucleosides using the Nicholas reaction

• Renata Kaczmarek,
• Dariusz Korczyński,
• James R. Green and
• Roman Dembinski

Beilstein J. Org. Chem. 2020, 16, 1–8, doi:10.3762/bjoc.16.1

• intramolecular versions of the reaction are also highly successful [50][51]. Although the Nicholas reaction has been employed to functionalize biomolecules, including amino acids [52][53], β-lactams [54], steroids [55], and carbohydrates [56][57][58][59][60][61][62], we are unaware of any examples of nucleoside

Regioselectivity of glycosylation reactions of galactose acceptors: an experimental and theoretical study

• Enrique A. Del Vigo,
• Carlos A. Stortz and
• Carla Marino

Beilstein J. Org. Chem. 2019, 15, 2982–2989, doi:10.3762/bjoc.15.294

• carbohydrates in living systems, oligosaccharides and other glycoconjugates are needed to carry out the corresponding glycobiological studies. The heterogeneity of carbohydrates from natural sources makes their isolation difficult, which results in synthesis being the best alternative to obtain the required

• amounts of carbohydrate-containing molecules. Due to the chemical nature of carbohydrates, with multiple possible linkage positions giving rise to different regioisomers, with two possible anomeric configurations, the chemical synthesis of complex oligosaccharides is difficult and a rather time-consuming

• molecular modeling approach. Results and Discussion For this study, ᴅ-Galp derivatives with both their OH-2 and OH-6 group blocked were required. The regioselective functionalization of carbohydrates is usually a difficult task due to the similar reactivity of secondary hydroxy groups [13]. We synthesized

Chemical synthesis of tripeptide thioesters for the biotechnological incorporation into the myxobacterial secondary metabolite argyrin via mutasynthesis

• David C. B. Siebert,
• Roman Sommer,
• Domen Pogorevc,
• Michael Hoffmann,
• Silke C. Wenzel,
• Rolf Müller and
• Alexander Titz

Beilstein J. Org. Chem. 2019, 15, 2922–2929, doi:10.3762/bjoc.15.286

• David C. B. Siebert Roman Sommer Domen Pogorevc Michael Hoffmann Silke C. Wenzel Rolf Muller Alexander Titz Chemical Biology of Carbohydrates, Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research (HZI), D-66123 Saarbrücken, Germany Deutsches

Indium-mediated C-allylation of melibiose

• Christian Denner,
• Manuel Gintner,
• Hanspeter Kählig and
• Walther Schmid

Beilstein J. Org. Chem. 2019, 15, 2458–2464, doi:10.3762/bjoc.15.238

• the elongated unit at the reducing end of the disaccharide. Keywords: carbohydrates; C–C bond formation; indium-mediated allylation; melibiose; ozonolysis; Introduction The tin and indium-mediated allylation (IMA) proved to be useful synthetic tools for the chain elongation of unprotected

• carbohydrates at the anomeric position to obtain higher complex sugar structures. Prior to the establishment of these methods, synthetic approaches towards these compounds had to be performed on protected carbohydrates, increasing the number of synthetic steps intrinsically [1]. In 1991, Schmid and Whitesides

• reported for the first time a tin-mediated allylation of unprotected carbohydrates followed by ozonolysis allowing for easy accessibility of the corresponding elongated sugars [2]. In the same year, Chan and Li introduced indium for the allylation of aldehydes and furthermore demonstrated the applicability

N-(1-Phenylethyl)aziridine-2-carboxylate esters in the synthesis of biologically relevant compounds

• Iwona E. Głowacka,
• Aleksandra Trocha,
• Andrzej E. Wróblewski and
• Dorota G. Piotrowska

Beilstein J. Org. Chem. 2019, 15, 1722–1757, doi:10.3762/bjoc.15.168

• for structural enlargement and at least one stereogenic center which is usually transferred into the final product. To assure the highest possible enantiomeric purity chirons are obtained in most instances from natural products like carbohydrates, amino acids, hydroxy acids or terpenes. The

Steroid diversification by multicomponent reactions

• Leslie Reguera,
• Cecilia I. Attorresi,
• Javier A. Ramírez and
• Daniel G. Rivera

Beilstein J. Org. Chem. 2019, 15, 1236–1256, doi:10.3762/bjoc.15.121

• as the conjugation of steroids to amino acids, peptides and carbohydrates. We demonstrate that steroids are available with almost all types of MCR reactive functionalities, e.g., carbonyl, carboxylic acid, alkyne, amine, isocyanide, boronic acid, etc., and that steroids are suitable starting

• Conjugation of steroids to carbohydrates and peptides The conjugation of steroids to other biomolecules such as carbohydrates and peptides represents a valuable strategy for providing new properties to the hydrophobic steroid skeleton. Naturally occurring steroid–sugar conjugates such as saponins have shown

• ketosteroids [50][51]. Conjugation of steroids to carbohydrates and peptides by the Ugi-4CR [62][63]. Solid-phase multicomponent conjugation of peptides to steroids by the Ugi-4CR [64]. Solid-phase multicomponent conjugation of peptides to steroids by the Petasis-3CR [68]. Synthesis of steroidal macrobicycles

Stereo- and regioselective hydroboration of 1-exo-methylene pyranoses: discovery of aryltriazolylmethyl C-galactopyranosides as selective galectin-1 inhibitors

• Alexander Dahlqvist,
• Axel Furevi,
• Niklas Warlin,
• Hakon Leffler and
• Ulf J. Nilsson

Beilstein J. Org. Chem. 2019, 15, 1046–1060, doi:10.3762/bjoc.15.102

• /bjoc.15.102 Abstract Galectins are carbohydrate recognition proteins that bind carbohydrates containing galactose and are involved in cell signaling and cellular interactions, involving them in several diseases. We present the synthesis of (aryltriazolyl)methyl galactopyranoside galectin inhibitors

• ; galectin-1; hydroboration; inhibition; selective; triazole; Introduction Galectins are defined by a typically about 130 amino acid carbohydrate recognition domain (CRD) that binds to carbohydrates with at least one β-galactose subunit within a binding pocket large enough to accommodate a tetrasaccharide

Catalytic asymmetric oxo-Diels–Alder reactions with chiral atropisomeric biphenyl diols

• Chi-Tung Yeung,
• Wesley Ting Kwok Chan,
• Wai-Sum Lo,
• Ga-Lai Law and
• Wing-Tak Wong

Beilstein J. Org. Chem. 2019, 15, 955–962, doi:10.3762/bjoc.15.92

• stereogenic centers in a one-step [4 + 2] cycloaddition or cyclization reaction [6][7][8] and it has become hugely popular in preparing vital intermediates for the syntheses of key structural subunits of natural products with biological activities (e.g., carbohydrates, antibiotics, toxins etc.) [9][10

Design and synthesis of multivalent α-1,2-trimannose-linked bioerodible microparticles for applications in immune response studies of Leishmania major infection

• Chelsea L. Rintelmann,
• Tara Grinnage-Pulley,
• Kathleen Ross,
• Daniel E. K. Kabotso,
• Angela Toepp,
• Anne Cowell,
• Christine Petersen,
• Balaji Narasimhan and
• Nicola Pohl

Beilstein J. Org. Chem. 2019, 15, 623–632, doi:10.3762/bjoc.15.58

• recognition by pathogen-recognition receptors during L. major-induced leishmaniasis. Keywords: adjuvant; carbohydrates; L. major; microparticle; PAMP; Introduction Recognition of parasite cell surface molecules by host immune cells initiates the first step in the immune response [1][2]. The host’s immune

• manuscript and analyzed the data. CR, TG, KR, DK, AT, AC, CP, BN and NP all assisted with data interpretation and the final manuscript preparation. CP and NP supervised the collaboration. Funding Grinnage-Pulley, T., Petersen, CA, Narasimhan, B., Pohl, N, “Role of pathogen-derived capping carbohydrates in

Cyclopropene derivatives of aminosugars for metabolic glycoengineering

• Jessica Hassenrück and
• Valentin Wittmann

Beilstein J. Org. Chem. 2019, 15, 584–601, doi:10.3762/bjoc.15.54

• , distinct cell-surface staining after MGE. We further found that the amide-linked Cp-modified glucosamine derivative but not the Cyoc-modified glucosamine is metabolically converted to the corresponding sialic acid. Keywords: bioorthogonal chemistry; carbohydrates; cyclopropenes; inverse electron-demand

• Diels–Alder reaction; metabolic engineering; Introduction Carbohydrates are an important class of biological molecules involved in many fundamental biological processes [1]. An important tool to visualize glycoconjugates in vitro and in vivo is metabolic glycoengineering (MGE) [2][3][4]. In this

First synthesis of cryptands with sucrose scaffold

• Patrycja Sokołowska,
• Michał Kowalski and
• Sławomir Jarosz

Beilstein J. Org. Chem. 2019, 15, 210–217, doi:10.3762/bjoc.15.20

• ring, functional groups etc. Carbohydrates are especially useful platforms for macrocycles being able to recognize enantiomers. Special attention is directed to native and modified cyclodextrins, cyclic oligosaccharides, which have found wide application in many aspects of chemistry and industry [3][4

Lectins of Mycobacterium tuberculosis – rarely studied proteins

• Katharina Kolbe,
• Sri Kumar Veleti,
• Norbert Reiling and
• Thisbe K. Lindhorst

Beilstein J. Org. Chem. 2019, 15, 1–15, doi:10.3762/bjoc.15.1

• ). In this paper we review previous studies on the carbohydrate-binding characteristics of mycobacteria and related Mtb proteins, discussing their potential relevance to Mtb infection and pathogenesis. Keywords: adhesion; carbohydrates; fimbriae; lectins; Mycobacterium tuberculosis; pili; Introduction

• invasion of host cells is a complex process, which is initiated by interactions between host and bacterial cell surface structures. As shown in previous studies, host cells can bind to mycobacterial cell wall carbohydrates via a class of surface-localized or secreted proteins known as lectins, and these

• '-dimycolate (TDM) and its precursor trehalose 6-monomycolate (TMM) [55]. Mycobacteria therefore possess α-D-mannopyranosides, α-D-arabinofuranosides, α-D-glucopyranosides, α-D-galactofuranosides, and their associated oligomeric forms as surface-exposed carbohydrates accessible to extracellular protein

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

• Matthew B. Calvert Varsha R. Jumde Alexander Titz Chemical Biology of Carbohydrates, Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research (HZI), D-66123 Saarbrücken, Germany Deutsches Zentrum für Infektionsforschung (DZIF), Standort Hannover

Semi-synthesis and insecticidal activity of spinetoram J and its D-forosamine replacement analogues

• Kai Zhang,
• Jiarong Li,
• Honglin Liu,
• Haiyou Wang and
• Lamusi A

Beilstein J. Org. Chem. 2018, 14, 2321–2330, doi:10.3762/bjoc.14.207

• ether bond at the C17 position under acidic conditions. Synthesis of spinetoram J analogues All carbohydrates and alcohols were activated by CNCCl3 with DBU as catalyst initially to afford glycoside donors, and then the 17-pseudoaglycone of spinetoram J was glycosylated with donors in the presence of

Synthesis of 1,4-imino-L-lyxitols modified at C-5 and their evaluation as inhibitors of GH38 α-mannosidases

• Maroš Bella,
• Sergej Šesták,
• Ján Moncoľ,
• Miroslav Koóš and
• Monika Poláková

Beilstein J. Org. Chem. 2018, 14, 2156–2162, doi:10.3762/bjoc.14.189

• ; inhibitors; pyrrolidines; synthesis; Introduction Carbohydrates as chiral templates for a construction of bioactive compounds are of steady interest in medicinal chemistry [1][2][3]. The polyfunctional nature of carbohydrate units offers many possibilities for the design of a wide variety of new compounds

D-Fructose-based spiro-fused PHOX ligands: synthesis and application in enantioselective allylic alkylation

• Michael R. Imrich,
• Jochen Kraft,
• Cäcilia Maichle-Mössmer and
• Thomas Ziegler

Beilstein J. Org. Chem. 2018, 14, 2082–2089, doi:10.3762/bjoc.14.182

• the Ritter reaction with ether-protected carbohydrates is β as well, 10j was benzylated and 10b was obtained (Scheme 4). This proves the structure of 10b as well. The ratio of the anomers produced by the Ritter reaction depends on the substitution pattern of the pyranoside used and varies from only β

Diazirine-functionalized mannosides for photoaffinity labeling: trouble with FimH

• Femke Beiroth,
• Tomas Koudelka,
• Thorsten Overath,
• Stefan D. Knight,
• Andreas Tholey and
• Thisbe K. Lindhorst

Beilstein J. Org. Chem. 2018, 14, 1890–1900, doi:10.3762/bjoc.14.163

• ; Introduction The investigation of the interactions between proteins and their ligands, such as lectins and carbohydrates, is of fundamental importance for the understanding of many biological processes. Several different methodologies are used for the elucidation of ligand–protein interactions. In addition to

A hemicryptophane with a triple-stranded helical structure

• Augustin Long,
• Olivier Perraud,
• Erwann Jeanneau,
• Christophe Aronica,
• Jean-Pierre Dutasta and
• Alexandre Martinez

Beilstein J. Org. Chem. 2018, 14, 1885–1889, doi:10.3762/bjoc.14.162

• part). They display recognition properties toward neurotransmitters and carbohydrates, and can act as molecular switches and supramolecular catalysts [11]. Their C3 symmetry makes them promising candidates to build molecular cages displaying a triple helical arrangement of the linkers. Furthermore, we

Anomeric modification of carbohydrates using the Mitsunobu reaction

• Julia Hain,
• Patrick Rollin,
• Werner Klaffke and
• Thisbe K. Lindhorst

Beilstein J. Org. Chem. 2018, 14, 1619–1636, doi:10.3762/bjoc.14.138

• this is important to explain and predict the stereoselectivity of anomeric modifications under Mitsunobu conditions. Though the Mitsunobu reaction is often not the first choice for the anomeric modification of carbohydrates, this review shows the high value of the reaction in many different

• circumstances. Keywords: anomeric stereoselectivity; carbohydrates; glycoside synthesis; Mitsunobu reaction; Introduction Fifty years ago, Oyo Mitsunobu reported a preparation of esters from alcohols and carboxylic acids supported by two auxiliary reagents, diethyl azodicarboxylate (DEAD) and

• anomeric modification of carbohydrates. The reaction proceeds under mild, neutral conditions that are compatible with a wide range of functional groups. In the case where a stereogenic center is involved, the reaction takes place with stereochemical inversion [6]. The reaction partners are mostly primary

Glycosylation reactions mediated by hypervalent iodine: application to the synthesis of nucleosides and carbohydrates

• Yuichi Yoshimura,
• Hideaki Wakamatsu,
• Yoshihiro Natori,
• Yukako Saito and
• Noriaki Minakawa

Beilstein J. Org. Chem. 2018, 14, 1595–1618, doi:10.3762/bjoc.14.137

• , similar deformylation by action of hypervalent iodine has also been demonstrated: the β-fragmentation reaction of an anomeric alkoxy radical of carbohydrates was mediated by a hypervalent iodine reagent [73]. The reaction results in the formation of carbohydrates with a reduction of one carbon. From the

• yields for the one-pot process are comparable or superior to those obtained with the two-step procedure (Scheme 18). Synthesis of disaccharides Classically, carbohydrates have been considered primarily an energy source for life – as in the cases of glucose, fructose and their oligosaccharides, e.g

Synthetic avenues towards a tetrasaccharide related to Streptococcus pneumonia of serotype 6A

• Aritra Chaudhury,
• Mana Mohan Mukherjee and
• Rina Ghosh

Beilstein J. Org. Chem. 2018, 14, 1095–1102, doi:10.3762/bjoc.14.95

• oligosaccharide synthesis. We have synthesized the aforesaid tetrasaccharide (SPn 6A) based on both stepwise and sequential one-pot glycosylation reactions using easily accessible common building blocks; eventually similar overall yields were obtained in both cases. Keywords: carbohydrates; glycosylation