72959-81-0Relevant articles and documents
Nucleophilic displacement-reactions of the 4-sulfonyloxy group in derivatives having the D-manno configuration
Cicero, Daniel,Varela, Oscar,Lederkremer, Rosa M. de
, p. 295 - 308 (1991)
Methyl 2,3-di-O-benzoyl-6-deoxy-4-O-(p-tolylsulfonyl) and 4-O--α-D-mannopyranosides (9 and 10) were prepared by three different routes from methyl α-D-mannopyranoside (1).The analogous 4-sulfonyloxy derivatives having HO-2 and HO-3 free (14 and 15) were also synthesized from 1.Nucleophilic substitution of the sulfonyloxy group of 9, 10, 14, and 15 by potassium thiocyanate in N,N-dimethylformamide was attempted.Compounds 9 and 10 gave a mixture of solvolysis products: methyl 2,3-di-O-benzoyl-6-deoxy-α-D-talopyranoside (17), methyl 3,4-di-O-benzoyl-6-deoxy-α-D-talopyranoside (18), and methyl 2,4-di-O-benzoyl-6-deoxy-α-D-talopyranoside (19), which are evidently formed by intramolecular displacement of the 4-sulfonate by backside attack of the C-2 benzoyloxy substituent, followed by benzoyl migration.The structure of compounds 17-19 was established by spectroscopic analysis, and then chemically confirmed.Although compound 14 decomposed during the substitution reaction, the 4-p-nitrophenylsulfonyl derivative 15 gave a 2:1 mixture of the 4-thiocyano derivatives with inversion and retention of the C-4 configuration.
USE OF FUCOSYLATION INHIBITOR FOR PRODUCING AFUCOSYLATED ANTIBODY
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, (2021/06/26)
The present invention provides inhibitors of fucosylation during protein expression from mammalian cells. The inhibitors are derived from rhamnose and act by inhibition of GDP-mannose 4,6-dehydratase (GMD). The invention further provides methods of making
Synthetic glycoconjugates characterize the fine specificity of: Brucella A and M monoclonal antibodies
Mandal, Satadru Sekhar,Ganesh, N. Vijaya,Sadowska, Joanna M.,Bundle, David R.
, p. 3874 - 3883 (2017/07/11)
The dominant cell wall antigen of Brucella bacteria is the O-polysaccharide component of the smooth lipopolysaccharide. Infection by various Brucella biovars causes abortions and infertility in a wide range of domestic and wild animals and debilitating disease in humans. Diagnosis relies on the detection of antibodies to the A and M antigens expressed in the O-polysaccharide. This molecule is a homopolymer of the rare monosaccharide, 4-formamido-4,6-dideoxy-d-mannopyranose (Rha4NFo). The A epitope is created by a uniform α1,2 linked internal polymeric sequence capped by a distinct tetrasaccharide sequence defining the M antigen. Unique oligosaccharides only available by chemical synthesis and conjugated via reducing and non-reducing residues to bovine serum albumin have revealed the structural basis of the fine specificity that allows the discrimination of these closely related A and M epitopes. All three M specific monoclonal antibodies (mAbs) are inferred to possess groove type binding sites open at each end, and recognize an α1,3 linked Rha4NFo disaccharide as a part of a trisaccharide epitope, which in two mAbs includes the terminal Rha4NFo residue. The binding site of one of these antibodies is sufficiently large to engage up to six Rha4NFo residues and involves weak recognition of α1,2 linked Rha4NFo residues. The third mAb binds an internal trisaccharide epitope of the M tetrasaccharide. Two A specific mAbs also possess groove type binding sites that accommodate six and four α1,2 linked Rha4NFo residues.
Mechanistic investigation of the radical S -adenosyl- L -methionine enzyme DesII using fluorinated analogues
Lin, Geng-Min,Choi, Sei-Hyun,Ruszczycky, Mark W.,Liu, Hung-Wen
, p. 4964 - 4967 (2015/05/05)
DesII is a radical S-adenosyl-l-methionine (SAM) enzyme that can act as a deaminase or a dehydrogenase depending on the nature of its TDP-sugar substrate. Previous work has implicated a substrate-derived, C3-centered α-hydroxyalkyl radical as a key interm
Bio-inspired synthesis of rare and unnatural carbohydrates and cyclitols through strain driven epimerization
Mohanrao, Raja,Asokan, Aromal,Sureshan, Kana M.
supporting information, p. 6707 - 6710 (2014/06/23)
We report a bio-inspired, strain driven epimerization of trans-ketals to cis-ketals through an enolate intermediate. Swern oxidation of a hydroxyl group adjacent to a trans-ketal effects both oxidation and its epimerization to cis-ketal. This novel and general strategy allows inversion of up to three contiguous stereocenters and has been illustrated by the synthesis of several unnatural/rare isomers of carbohydrates/cyclitols from their naturally abundant isomers. This journal is the Partner Organisations 2014.
Molecular recognition of brucella A and M antigens dissected by synthetic oligosaccharide glycoconjugates leads to a disaccharide diagnostic for brucellosis
Ganesh, N. Vijaya,Sadowska, Joanna M.,Sarkar, Susmita,Howells, Laurence,McGiven, John,Bundle, David R.
, p. 16260 - 16269 (2015/01/09)
The cell wall O-polysaccharides of pathogenic Brucella species are homopolymers of the rare sugar 4,6-dideoxy-4-formamido- α-d-mannopyranose. Despite the apparent simplicity of the polysaccharide it appears to be a "block copolymer" composed of A and M polysaccharide sequences expressed as a single molecule. The simultaneous presence of both in the cell wall has complicated the understanding of the molecular recognition of these antigens by antibodies present in the serum of infected animals and humans and by monoclonal antibodies. Since presumptive diagnosis of brucellosis, a serious disease in domestic livestock, wild animals, and humans, is based on detection of these antibodies it is important to separate the two antigenic epitopes, one of which is also found in other bacteria. Chemical synthesis provides the only means to achieve this outcome. A series of six oligosaccharides from di to hexasaccharides 1-6 were synthesized and conjugated to proteins to provide glycoconjugate antigens and conjugate vaccines. These chemically defined antigens identified the M antigenic determinant and provided a structural basis for understanding the fine specificity of monoclonal and polyclonal antibodies that bind the M antigen. This resulted in the discovery of a disaccharide that shows considerable potential as an unambiguous diagnostic antigen for detecting brucellosis in humans and animals and two hexasaccharide conjugate vaccine candidates that produce high levels of O-polysaccharide specific antibodies in mice.
Probe sialidase substrate specificity using chemoenzymatically synthesized sialosides containing C9-modified sialic acid
Khedri, Zahra,Muthana, Musleh M.,Li, Yanhong,Muthana, Saddam M.,Yu, Hai,Cao, Hongzhi,Chen, Xi
, p. 3357 - 3359 (2012/05/04)
A library of α2-3- and α2-6-linked sialyl galactosides containing C9-modified sialic acids was synthesized from C6-modified mannose derivatives using an efficient one-pot three-enzyme system. These sialosides were used in a high-throughput sialidase substrate specificity assay to elucidate the importance of C9-OH in sialidase recognition. The Royal Society of Chemistry 2012.
Synthesis of orthogonally protected d-olivoside, 1,3-di-O-acetyl-4-O-benzyl-2,6-dideoxy-d-arabinopyranose, as a C-glycosyl donor
Osman, Hasnah,Larsen, David S.,Simpson, Jim
body text, p. 4092 - 4098 (2009/09/30)
1,3-Di-O-acetyl-4-O-benzyl-2,6-dideoxy-d-arabinopyranose (11) was synthesised from thiophenyl α-d-mannopyranoside (21) in an eight-step sequence. Tosylation of 21 and subsequent reaction with 2,2-dimethoxypropane gave tosylate 22, which upon treatment with lithium aluminium hydride furnished 6-deoxy glycoside 24 and by-product thiophenyl 6-deoxy-2-O-isopropyl-α-d-arabinopyranoside. The X-ray crystal structure of the latter was determined. Benzylation of the 4-hydroxyl group of 24 and subsequent protecting group manipulation gave d-rhamnosyl bromide 29, which on treatment with zinc-copper couple gave the orthogonally protected d-rhamnal 30. Triphenylphosphine hydrogen bromide catalysed addition of acetic acid to 30 furnished the target molecule 11. The scandium(III) triflate promoted reaction of 11 and 2-naphthol gave the corresponding C-glycoside 36 in 86% yield. Crown Copyright
Synthesis and biological evaluation of enantiomeric rhamnose analogues of the antitumour agent spicamycin - Is the mode of action by modification of N-linked glycoproteins?
Martin, Angeles,Butters, Terry D.,Fleet, George W. J.
, p. 2343 - 2360 (2007/10/03)
The synthesis of both enantiomers of dodecyl rhamnospicamycin 2a and 2b, a rhamnose analogue of the naturally occurring combinatorial library spicamycin 1, are derived from L-rhamnose and methyl α-D-mannopyranoside, respectively. The L-(+)-enantiomer 2a c
The use of a new magnesium-derived hydride reagent for carbohydrate derivatives
Szabovik,Medgyes,Antal,Varga,Knott,Liptak
, p. 1003 - 1009 (2007/10/03)
The magnesium hydride based reagent in THF solution is an excellent tool for the stereoselective reduction of different uloside derivatives. Sugar azides, sulfonyl esters give aminosugars and methylose derivatives without affecting other functionalities. Halogenated sugars or methylene derivatives are stable under these conditions. The reagent can be applied in the presence of a wide variety of blocking groups (acetals, benzyl and allyl ethers, imides, C=C bonds) generally used in the carbohydrate chemistry.
