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Search for "glycosylation" in Full Text gives 185 result(s) in Beilstein Journal of Organic Chemistry.
Beyond symmetric self-assembly and effective molarity: unlocking functional enzyme mimics with robust organic cages
Beilstein J. Org. Chem. 2025, 21, 421–443, doi:10.3762/bjoc.21.30
- nucleophile and electrophile in a glycosylation reaction [105]. (D) An externally charged cavitand promotes charge-stabilized nucleophilic substitution reactions of hydrophobically encapsulated substrates [136][137]. (A) Metal-organic cages and key modes in catalysis. (B) Charged metals or ligands can result
The effect of neighbouring group participation and possible long range remote group participation in O-glycosylation
Beilstein J. Org. Chem. 2025, 21, 369–406, doi:10.3762/bjoc.21.27
- multistep synthesis of complex oligosaccharides and in turn, standardise the process of the glycosylation towards a particular stereochemical output. While neighbouring group participation has been quite effective in achieving the required stereochemistry of the produced glycosides, remote participation
- exhibits comparatively less efficacy in achieving complete stereoselectivity in the glycosylation reactions. Remote participation is a still highly debated topic in the scientific community. However, implementing the participating role of the remote groups in glycosylation reactions is widely practised to
- achieve better stereocontrol and to facilitate the formation of synthetically challenging glycosidic linkages. Keywords: chemical O-glycosylation; neighbouring group participation; remote group participation; solvent effect; stereocontrol; Introduction Cell surface glycans in living cells have
N-Glycosides of indigo, indirubin, and isoindigo: blue, red, and yellow sugars and their cancerostatic activity
Beilstein J. Org. Chem. 2024, 20, 2840–2869, doi:10.3762/bjoc.20.240
- (4a) initially resulted in the glycosylation of the oxygen atom to give intermediate A (−20 °C, 1.5 h). Extension of the reaction time (20 °C, 12 h) afforded N-indigoglycoside 5a which was isolated in 35% yield. The product contained an α-rhamnosyl moiety with 4C1 conformation. The formation of the
- (Scheme 4) [20]. The reaction of 1b with 3,4,6-tri-O-acetyl-2-O-benzoyl-α-ᴅ-glucosyl trichloroacetimidate (6a) afforded indigo-N-glycoside 7a. The benzoyl group located at OH-2 seemed to be unreactive enough to avoid formation of orthoester-like amide acetals during the N-glycosylation with 1b. Oxidative
- sodium tert-butanolate afforded the desired deprotected indigo-N-rhamnoside 5d (α/β = 2:1). In contrast to the antiproliferative properties of the akashins, 5d showed no significant activity against human cancer cell lines. The glycosylation of 13 can be explained as follows (Scheme 9): Reaction of tetra
Improved deconvolution of natural products’ protein targets using diagnostic ions from chemical proteomics linkers
Beilstein J. Org. Chem. 2024, 20, 2323–2341, doi:10.3762/bjoc.20.199
- -step synthesis. However, in comparison to the DMP-tag or AzidoTMT the release of the reporter ion from the SOX-tag has somewhat lower intensity. Calle et al. designed, synthesized, and validated a series of ‘clickable’ linkers for characterization of protein O-glycosylation containing positively
Computational toolbox for the analysis of protein–glycan interactions
Beilstein J. Org. Chem. 2024, 20, 2084–2107, doi:10.3762/bjoc.20.180
- -translational modifications, including glycosylation, in which a carbohydrate chain is directly attached to a specific amino acid to generate glycoproteins and proteoglycans [27]. Based on the amino acid involved in the link with the carbohydrates chain, it is possible to classify different types of
- glycosylation: i) N-glycosylation, where a N-acetylglucosamine (GlcNAc) is linked to the nitrogen atom of an asparagine side chain [28]; ii) O-glycosylation, where a GlcNAc or N-acetylgalactosamine (GalNAc) is linked to the hydroxy group of a serine or threonine residue [29]; iii) C-glycosylation, where a
- , flexibility, and heterogeneity. In particular, the Re-glyco tool allows the user to restore the missing glycosylation on glycoproteins deposited in the RCSB PDB or in the EBI-EMBL AlphaFold protein structure database (https://glycoshape.org/). The quality of the generated protein model is contingent on
Chemo-enzymatic total synthesis: current approaches toward the integration of chemical and enzymatic transformations
Beilstein J. Org. Chem. 2024, 20, 1693–1712, doi:10.3762/bjoc.20.151
- catalysis with chemical synthesis [86]. By taking advantage of the chemo-enzymatically accessible 4, Sherman and co-workers further implemented the systematic total synthesis of juvenimicins and the M-4365 series via enzymatic and chemical late-stage modifications (Scheme 8B) [68]. In vivo glycosylation
Photoswitchable glycoligands targeting Pseudomonas aeruginosa LecA
Beilstein J. Org. Chem. 2024, 20, 1486–1496, doi:10.3762/bjoc.20.132
- commercially available p,p’-dihydroxyazobenzene (6), by using our recently developed DMC (2-chloro-1,3-dimethylimidazolinium chloride)-mediated one-pot glycosylation method in water [28], followed by O-alkylation of the remaining hydroxy group with BrCH2CH2NHBoc and acidic deprotection (Scheme 1). Three
- equivalents of dihydroxyazobenzene 6 were used for the selective monoglycosylation step, with the excess of azobenene being recovered after column chromatography. Under these conditions, no bisglycosylated azobenzene was observed [28]. The observed 1,2-trans glycosylation could be explained either by the
- β-O-galactoside [36]. The same strategy was applied for the m,m’-substituted derivative 2, starting from the glycosylation of m,m’-dihydroxyazobenzene (9) [37], followed by O-alkylation and Boc deprotection to afford the galacoside 2 in 19% total yield. Unfortunately, all our attempts to synthesize
Synthesis of cyclic β-1,6-oligosaccharides from glucosamine monomers by electrochemical polyglycosylation
Beilstein J. Org. Chem. 2024, 20, 1421–1427, doi:10.3762/bjoc.20.124
- protecting group afforded the cyclic disaccharide exclusively. Cyclic oligosaccharides up to the trisaccharide were obtained using the monomer with a 2-azido-2-deoxy group. Keywords: cyclic oligosaccharide; electrochemical glycosylation; glucosamine; polyglycosylation; Introduction Electrochemical
- ][7][8][9][10]. Thus, chemical glycosylation has to be improved to be able to synthesize complex oligosaccharides, including cyclic oligosaccharides. In this context, electrochemical glycosylation is an important alternative to conventional chemical glycosylations because the precise control of
- intramolecular glycosylation (Scheme 1a) [14]. One-pot two-step synthesis via electrochemical polyglycosylation and intramolecular glycosylation has also been achieved in order to synthesize unnatural cyclic oligosaccharides of glucosamine (Scheme 1b) [15]. Here, we report the direct synthesis of cyclic
Monitoring carbohydrate 3D structure quality with the Privateer database
Beilstein J. Org. Chem. 2024, 20, 931–939, doi:10.3762/bjoc.20.83
- complement the growing glycan content of the PDB. Keywords: carbohydrates; database; N-glycans; N-glycosylation; polysaccharides; validation; website; Introduction Carbohydrate modelling is an important but often cumbersome stage in the macromolecular X-ray structure solution workflow. The accurate
- calculated by Privateer and, most importantly, the diagnostic provided by Privateer (Figure 4). A ‘yes’ diagnostic indicates the conformation is correct for the glycosylation type (e.g., 4C1 for GlcNAc in an N-glycan, 1C4 for mannose in a C-glycan), has the correct anomer, and has an acceptable fit to
- interface on the Privateer database homepage, carbohydrate-containing PDB entries can easily be found and filtered. Privateer database entries for specific glycosylation types, namely, N-glycosylation, O-glycosylation, S-glycosylation, or C-glycosylation can be filtered quickly and easily. Additional
Research progress on the pharmacological activity, biosynthetic pathways, and biosynthesis of crocins
Beilstein J. Org. Chem. 2024, 20, 741–752, doi:10.3762/bjoc.20.68
- ), or zeaxanthin (7) by a carotenoid cleavage dioxygenase (CCD) to form crocetin aldehyde (8) and, after oxidation, 1, and 3) glycosylation of 1 to generate crocins (Figure 3). Since the biosynthetic pathways of 5 in plants and microorganisms have been elucidated and reviewed, we will only elaborate the
- crocins The late steps in crocin biosynthesis are the glycosylation of crocetin (1) by various UGTs [86]. The crocin biosynthetic pathways in G. jasminoides have been characterized in detail, and several GjUGTs were identified. Attributed to different substrate specificities, the glucose or gentiobiose
- that it was able to convert crocetin dialdehyde (8) into crocetin (1) in vitro [100]. BdALDH and CsALDH3I1 belong to the ALDH3 family, one of the most diverse groups of the ALDH superfamily. UGTs: Glycosylation of crocetin (1) improves the solubility significantly [101][102]. Moraga et al. cloned two
Chemoenzymatic synthesis of macrocyclic peptides and polyketides via thioesterase-catalyzed macrocyclization
Beilstein J. Org. Chem. 2024, 20, 721–733, doi:10.3762/bjoc.20.66
- overall yield. According to the biosynthetic approach, these macrolides are produced by the type I PKS system, including thioesterase (TE)-catalyzed cyclization of the linear hexa- and heptaketide intermediates, post-PKS oxidation, and glycosylation [67]. Cane and co-workers reported that Pik TE, the TE
- macrolactonization, leading to the formation of tylactone (39) in 69% yield. Furthermore, the Streptomyces strain S. venezuelae DHS316 [76] performed an in vivo glycosylation resulting in M-4365 G1 (50) in 15 linear steps and 4.6% overall yield from commercial resources. With regio- and stereoselective C–H
Introduction of a human- and keyboard-friendly N-glycan nomenclature
Beilstein J. Org. Chem. 2024, 20, 607–620, doi:10.3762/bjoc.20.53
- greatly facilitate keyboard-based mining for glycan substructures in glycan repositories. Keywords: N-glycans; nomenclature; structural features; Introduction Virtually any article on protein glycosylation starts with imposing assurances about the biological significance of the various structures. This
- “proglycan” nomenclature, an acronym derived from our then nom de guerre “protein-glycosylation analysis” group. By the way, glycan analysis also funneled in activities in the area of allergy diagnosis, where the term MUXF3 enjoys widespread use [38][39][40]. Finally, our work on the isomer-specific analysis
Elucidating the glycan-binding specificity and structure of Cucumis melo agglutinin, a new R-type lectin
Beilstein J. Org. Chem. 2024, 20, 306–320, doi:10.3762/bjoc.20.31
- profiling, thereby advancing both diagnostic methods and biomarker discovery. Examples include arrays that can rapidly profile alterations in glycosylation patterns, pivotal in many diseases and inflammatory changes [10][11]. Traditionally, lectins are divided into classes based on structural similarity and
- ). In parallel, we also expressed CMA1 in a bacterial expression system, which allowed us to ascertain whether binding was influenced by lectin glycosylation. The full-length mature protein (6–264) and individual N- or C-terminal domains were expressed using a N-terminal fusion comprising DsbC and a
- binding in solution and a further confirmation of the binding specificity obtained by the array experiments. We note that the functional activity of bacterially produced CMA1 indicates that potential modification by glycosylation is not required for ligand binding. Next, we set out to quantify the binding
Optimizations of lipid II synthesis: an essential glycolipid precursor in bacterial cell wall synthesis and a validated antibiotic target
Beilstein J. Org. Chem. 2024, 20, 220–227, doi:10.3762/bjoc.20.22
- bacteria. Accessing this valuable cell wall precursor is important both for studying cell wall synthesis and for studying/identifying novel antimicrobial compounds. Herein, we describe optimizations to the modular chemical synthesis of lipid II and unnatural analogues. In particular, the glycosylation step
- analogues through the incorporation of alternative building blocks at different stages of synthesis. Keywords: chemical glycosylation; lipid II; peptidoglycan; polyprenyls; total synthesis; Introduction Lipid II (Figure 1) is an essential bacterial glycolipid involved in peptidoglycan biosynthesis [1]. It
- describe herein. The base lipid II syntheses upon which optimizations were made are our previously reported syntheses of Gram-negative lipid II in 2016 [20] and Gram-positive lipid II (11) in 2018 [23]. Building upon these synthetic strategies we have achieved noteworthy enhancements in glycosylation
Comparison of glycosyl donors: a supramer approach
Beilstein J. Org. Chem. 2024, 20, 181–192, doi:10.3762/bjoc.20.18
- , Russian Federation 10.3762/bjoc.20.18 Abstract The development of new methods for chemical glycosylation commonly includes comparison of various glycosyl donors. An attempted comparison of chemical properties of two sialic acid-based thioglycoside glycosyl donors, differing only in the substituent at O-9
- (trifluoroacetyl vs chloroacetyl), at different concentrations (0.05 and 0.15 mol·L−1) led to mutually excluding conclusions concerning their relative reactivity and selectivity, which prevented us from revealing a possible influence of remote protective groups at O-9 on glycosylation outcome. According to the
- and straightforward as it is usually considered. Keywords: concentration; glycosylation; protecting groups; reactivity; sialic acids; stereoselectivity; Introduction Glycoconjugates containing sialic acid occur on the surface of all cell types in a variety of organisms. They participate in a broad
Synthesis of the 3’-O-sulfated TF antigen with a TEG-N3 linker for glycodendrimersomes preparation to study lectin binding
Beilstein J. Org. Chem. 2024, 20, 173–180, doi:10.3762/bjoc.20.17
- glycosylation reactions. The 3’-sulfate was finally introduced through tin activation in benzene/DMF followed by treatment with a sulfur trioxide–trimethylamine complex in a 66% yield. Keywords: regioselective sulfation; thioglycoside donors; Thomsen–Friedenreich antigen; Introduction In a collaboration
- at this stage was predicted to be problematic. Therefore, the azido functionality was installed in the spacer before the glycosylation. Donor 3 underwent an NIS/AgOTf-promoted glycosylation with the TEG-N3 acceptor [18], furnishing α-linked 4 in an 85% yield (Scheme 1). H-1 appeared as a doublet at
- choice [12], surprisingly better than a benzoylated donor [19], why this donor was the first one tested also with the quite different acceptor 5. An NIS/AgOTf-promoted glycosylation with donor 6 [20] yielded 79% of disaccharide 7. Due to the presence of rotamers, NMR spectra of 7 proved to be difficult
Synthesis of ether lipids: natural compounds and analogues
Beilstein J. Org. Chem. 2023, 19, 1299–1369, doi:10.3762/bjoc.19.96
Linker, loading, and reaction scale influence automated glycan assembly
Beilstein J. Org. Chem. 2023, 19, 1015–1020, doi:10.3762/bjoc.19.77
- (BBs) [1][2]. Iterative cycles of glycosylation, capping, and selective deprotection afford the support-bound glycan with a programmable sequence (Figure 1A). The protected glycan is then cleaved from the solid support and subjected to post-AGA deprotection steps to reveal the target glycan. AGA is
- , but isolated in relatively low yields. The optimization procedures are focused on glycan elongation (i.e., glycosylation and deprotection steps), whereas less attention is given to variables associated with the solid support [17]. In contrast, substantial knowledge exists on how loading [18], reaction
- increasing order of complexity, we prepared α-1,6-linked dimannosides (1,2) [32], branched trisaccharides (3,4) [12], and linear α-1,4-linked hexaglucosides (5,6) [15][33]. Each synthesis was performed with 6.5 equivalents of BB per glycosylation cycle using previously reported AGA conditions (see Supporting
Total synthesis of grayanane natural products
Beilstein J. Org. Chem. 2022, 18, 1707–1719, doi:10.3762/bjoc.18.181
- transformations include the removal of the ketone on the C ring, epoxide reductive opening, formation of the B ring exo-olefin, and glycosylation. In 2021, Hong et al. presented a synthetic effort focused on the synthesis of rhodojaponin III B–C rings [40]. The authors employed a Mn(III)-mediated intramolecular
Synthesis of protected precursors of chitin oligosaccharides by electrochemical polyglycosylation of thioglycosides
Beilstein J. Org. Chem. 2022, 18, 1133–1139, doi:10.3762/bjoc.18.117
- electrochemical polyglycosylation is also discussed, based on the oxidation potential of the monomer and oligosaccharides. Keywords: electrochemical glycosylation; glucosamine; oligosaccharide; oxidation potential; polyglycosylation; Introduction Chitin oligosaccharides are partial structures of chitin, which
- from natural sources or by synthesis via chemical glycosylation [2]. Total syntheses of chitin and chitosan oligosaccharides based on conventional chemical glycosylation of protected monosaccharides as building blocks have already been reported. Convergent synthesis using oligosaccharide building
- blocks can reduce the number of steps in the total synthesis. However, it requires manipulation of the anomeric leaving groups and deprotection of the protected hydroxy group at the 4-position prior to glycosylation. Although automated electrochemical assembly, which is a one-pot iterative synthesis of
Isolation and biosynthesis of daturamycins from Streptomyces sp. KIB-H1544
Beilstein J. Org. Chem. 2022, 18, 1009–1016, doi:10.3762/bjoc.18.101
- condensation between two molecules of α-keto acid. Structurally diverse p-terphenyls are formed from these key intermediates by several tailoring reactions such as cyclization, tautomerization, methylation, and glycosylation. A previous study has shown that the formation of 2,5-diarylcyclopentenone proceeds
GlycoBioinformatics
Beilstein J. Org. Chem. 2021, 17, 2726–2728, doi:10.3762/bjoc.17.184
- article by Barnett et al. [2] uses molecular dynamics to show that O-linked glycosylation alters peptide conformation, which influences the binding of the peptides to antibodies, despite the fact that glycans are not directly involved in the binding. Another molecular modeling article by Fogarty et al. [3
- one of the authors of this article, Fadda, used glyco-adapted molecular dynamics to explain in a separate publication [4] how the COVID-19 spike protein recognition element requires N-linked glycosylation to be exposed. Another approach to understanding glyco-interactions is described in a review
Synthetic strategies toward 1,3-oxathiolane nucleoside analogues
Beilstein J. Org. Chem. 2021, 17, 2680–2715, doi:10.3762/bjoc.17.182
- accompanied by coupling nucleobases via N-glycosylation. However, over the last three decades, efforts were made for the synthesis of 1,3-oxathiolane nucleosides by selective N-glycosylation of carbohydrate precursors at C-1, and this approach has emerged as a strong alternative that allows simple
- -oxathiolane ring with different nucleobases in a way that only one isomer is produced in a stereoselective manner via N-glycosylation. An emphasis has been placed on the C–N-glycosidic bond constructed during the formation of the nucleoside analogue. The third focus is on the separation of enantiomers of 1,3
- -oxathiolane nucleosides via resolution methods. The chemical as well as enzymatic procedures are reviewed and segregated in this review for effective synthesis of 1,3-oxathiolane nucleoside analogues. Keywords: chiral auxiliaries; enzymes; Lewis acids; N-glycosylation; 1,3-oxathiolane sugar and nucleosides
Halides as versatile anions in asymmetric anion-binding organocatalysis
Beilstein J. Org. Chem. 2021, 17, 2270–2286, doi:10.3762/bjoc.17.145
- macrocycle 81 (Scheme 17a) [78]. Compared to bis-thiourea 80, the higher rigidity in the macrocycle 81 not only enforces halide abstraction significantly, but also allowed for a better control of the stereoselectivity in the glycosylation of glycosyl halides 78 with a variety of coupling partners. In this
- diastereoselective glycosylation reaction. b) Competing SN1 vs SN2 reactivity. a) Folding mechanism of oligotriazoles upon anion recognition. b) Representative tetratriazole 82 catalyzed enantioselective Reissert-type reaction of quinolines and pyridines with various nucleophiles. Switchable chiral tetratriazole
Progress and challenges in the synthesis of sequence controlled polysaccharides
Beilstein J. Org. Chem. 2021, 17, 1981–2025, doi:10.3762/bjoc.17.129
- polymerization [18], C) chemical synthesis. The use of enzymes has undeniable advantages because it offers the possibility to use unprotected sugars as substrates and guarantees remarkable control of the regio- and stereoselectivity during glycosylation. Mono- or oligosaccharides bearing a reactive leaving group
- only small modifications, hampering the formation of unnatural polymers. Low glycosylation yields and product hydrolysis represent additional hurdles associated with enzymatic synthesis of polysaccharides [23]. With this approach, homopolymers are often obtained as non-uniform samples, because the
- synthetic steps. In general, BBs are equipped with a reactive anomeric LG to allow for glycosylation and suitable PGs to ensure regio- and stereocontrol [25]. Even though, in most cases, BB preparation follows straightforward protection/deprotection strategies, the low selectivity and yield of certain
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