A concise synthesis of single components of partially sulfated oligomannans

Mong, Kwok-Kong Tony; Shiau, Kai‐Sheng; Lin, Yu Hsien; Cheng, Kuang‐Chun; Lin, Chun‐Chi

doi:10.1039/c5ob01786f

Cited by 17 publications

(6 citation statements)

References 40 publications

(34 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The orthogonally protected mannosyl donor 26 , suitable for selective deprotection of positions 3 and 6 was elaborated from known thioglycoside 23 following published procedures ( Scheme 4 ). 32 First, compound 23 was subjected to 6- O -silylation using TBS-chloride and DMAP in pyridine which gave the silyl ether 24 in 93% yield. Next, the thioglycoside aglycon was removed by treatment of 24 with NIS/TFA to produce 25 in 92% yield, followed by subsequent introduction of the anomeric trichloroacetimidate according to R. Schmidt 33 which provided donor 26 in 88% yield.…”

Section: Resultsmentioning

confidence: 99%

Synthesis of a Pentasaccharide Fragment Related to the Inner Core Region of Rhizobial and Agrobacterial Lipopolysaccharides

et al. 2017

View full text Add to dashboard Cite

The pentasaccharide fragment α-d-Man-(1 → 5)-[α-d-Kdo-(2 → 4)-]α-d-Kdo-(2 → 6)-β-d-GlcNAc-(1 → 6)-α-d-GlcNAc equipped with a 3-aminopropyl spacer moiety was prepared by a sequential assembly of monosaccharide building blocks. The glucosamine disaccharide—as a backbone surrogate of the bacterial lipid A region—was synthesized using an 1,3-oxazoline donor, which was followed by coupling with an isopropylidene-protected Kdo-fluoride donor to afford a protected tetrasaccharide intermediate. Eventually, an orthogonally protected manno-configured trichloroacetimidate donor was used to achieve the sterically demanding glycosylation of the 5-OH group of Kdo in good yield. The resulting pentasaccharide is suitably protected for further chain elongation at positions 3, 4, and 6 of the terminal mannose. Global deprotection afforded the target pentasaccharide to be used for the conversion into neoglycoconjugates and “clickable” ligands.

show abstract

Section: Resultsmentioning

confidence: 99%

Synthesis of a Pentasaccharide Fragment Related to the Inner Core Region of Rhizobial and Agrobacterial Lipopolysaccharides

et al. 2017

View full text Add to dashboard Cite

show abstract

“…Several synthetic approaches to analogues of tetra- and pentasaccharides 1 have already been reported [ 22 , 23 , 24 , 25 , 26 , 27 , 28 ]. In those approaches, different types glycosyl donors have been employed.…”

Section: Resultsmentioning

confidence: 99%

A Concise Synthesis of a BODIPY-Labeled Tetrasaccharide Related to the Antitumor PI-88

et al. 2021

View full text Add to dashboard Cite

A convergent synthetic route to a tetrasaccharide related to PI-88, which allows the incorporation of a fluorescent BODIPY-label at the reducing-end, has been developed. The strategy, which features the use of 1,2-methyl orthoesters (MeOEs) as glycosyl donors, illustrates the usefulness of suitably-designed BODIPY dyes as glycosyl labels in synthetic strategies towards fluorescently-tagged oligosaccharides.

show abstract

“…The donor was formed by a first coupling step of the known α-(1→2)-connected trichloroacetimidate 18 (28) with the orthogonally protected primary alcohol 19 . Thioglycoside 19 was prepared according to the literature 16,29 and was equipped with a 3- O -naphthylmethyl protecting group, which could eventually also serve for incorporation of the D2 arm. Glycosylation of 19 was promoted by catalytic TMSOTf at room temperature in dichloromethane and afforded the α-(1→6)-linked mannotrioside 20 in 72% yield (Scheme 4).…”

Section: Resultsmentioning

confidence: 99%

Synthesis of an Undecasaccharide Featuring an Oligomannosidic Heptasaccharide and a Bacterial Kdo-lipid A Backbone for Eliciting Neutralizing Antibodies to Mammalian Oligomannose on the HIV-1 Envelope Spike

et al. 2019

View full text Add to dashboard Cite

Lipooligosaccharides (LOS) from the bacterium Rhizobium radiobacter Rv3 are structurally related to antigenic mammalian oligomannoses on the HIV-1 envelope glycoprotein spike that are targets for broadly neutralizing antibodies. Here, we prepared a hybrid structure of viral and bacterial epitopes as part of a vaccine design strategy to elicit oligomannose-specific HIV-neutralizing antibodies using glycoconjugates based on the Rv3 LOS structure. Starting from a Kdo2GlcNAc2 tetrasaccharide precursor, a central orthogonally protected mannose trichloroacetimidate donor was coupled to OH-5 of the innermost Kdo residue. To assemble larger glycans, the N-acetylamino groups of the glucosamine units were converted to imides to prevent formation of unwanted imidate byproducts. Blockwise coupling of the pentasaccharide acceptor with an α-(1→2)-linked mannotriosyl trichloroacetimidate donor introduced the D1-arm fragment. Glycosylation of O-6 of the central branching mannose with an α-(1→2)-α-(1→6)-linked mannotriosyl trichloroacetimidate donor unit then furnished the undecasaccharide harboring a D3-arm extension. Global deprotection yielded the 3-aminopropyl ligand, which was activated as an isothiocyanate or adipic acid succinimidoyl ester and conjugated to CRM197. However, representative oligomannose-specific HIV-neutralizing antibodies bound the undecasaccharide conjugates poorly. Possible reasons for this outcome are discussed herein along with paths for improvement.

show abstract

A concise synthesis of single components of partially sulfated oligomannans

Cited by 17 publications

References 40 publications

Synthesis of a Pentasaccharide Fragment Related to the Inner Core Region of Rhizobial and Agrobacterial Lipopolysaccharides

Synthesis of a Pentasaccharide Fragment Related to the Inner Core Region of Rhizobial and Agrobacterial Lipopolysaccharides

A Concise Synthesis of a BODIPY-Labeled Tetrasaccharide Related to the Antitumor PI-88

Synthesis of an Undecasaccharide Featuring an Oligomannosidic Heptasaccharide and a Bacterial Kdo-lipid A Backbone for Eliciting Neutralizing Antibodies to Mammalian Oligomannose on the HIV-1 Envelope Spike

Contact Info

Product

Resources

About