The role of the cyclic 2,3-N,O-carbamate protecting group in directing the selectivity of mannosylation reactions of diacetone-d-glucose, promoted by BSP/TfO via α-triflate intermediates, has been investigated through a combined computational and experimental approach. DFT calculations were used to locate the transition states leading to the α or β anomers. These data indicate the preferential formation of the β-adduct with mannosyl donors either equipped with the 4,6-O-benzylidene protection or without it. The synthetic results confirmed this preference, showing in both cases an α/β selectivity of 4:6. This highlights a role for the 2,3-N,O-carbamate in sharp contrast with what described in the case of 2,3-O-carbonate mannosyl donors.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/j.carres.2021.108421 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
2,3-Carbamate mannosamine glycosyl donors in glycosylation reactions of diacetone-d-glucose. An experimental and theoretical study.
Carbohydr Res
November 2021
Dipartimento di Biotecnologie Mediche e Medicina Traslazionale, Università degli Studi di Milano, Via Saldini 50, 20133 Milano, Italy. Electronic address:
The role of the cyclic 2,3-N,O-carbamate protecting group in directing the selectivity of mannosylation reactions of diacetone-d-glucose, promoted by BSP/TfO via α-triflate intermediates, has been investigated through a combined computational and experimental approach. DFT calculations were used to locate the transition states leading to the α or β anomers. These data indicate the preferential formation of the β-adduct with mannosyl donors either equipped with the 4,6-O-benzylidene protection or without it.
View Article and Find Full Text PDFIn a one pot procedure a series of novel triazole linked thiazolidinone derivatives 8a-g and 9a-g was prepared by condensation of (3aR,5S,6R,6aR)-6-((1-(4-chlorophenyl)-1H-1,2,3-triazol-4-yl)methoxy)-2,2-dimethyltetrahydro[2,3-d] [1,3]dioxole-5-carbaldehyde 7 with mercapto acids and primary amines in the presence of ZnCl2 under both microwave irradiation and conventional heating conditions. Compound 7 was prepared from diacetone D-glucose with oxidation followed by reduction, click reaction, primary acetonide deprotection and with oxidative cleavage. Characterization of new compounds has been done by means of IR, NMR, MS and elemental analysis.
View Article and Find Full Text PDFSynthesis of EFdA via a diastereoselective aldol reaction of a protected 3-keto furanose.
Org Lett
February 2015
Laboratory of Applied Bioorganic Chemistry, Graduate School of Agricultural Science, Tohoku University, Tsutsumidori-Amamiyamachi, Aoba-ku, Sendai 981-8555, Japan.
An efficient enantioselective total synthesis of EFdA, a remarkably potent anti-HIV nucleoside analogue with various favorable pharmacological profiles, has been achieved in 37% overall yield from diacetone-D-glucose by a 14-step sequence that features a highly diastereoselective installation of the tetrasubstituted stereogenic center at the C4' position, direct oxidative cleavage of an acetonide-protected diol derivative to an aldehyde, and one-pot 2'-deoxygenation of a ribonucleoside intermediate.
View Article and Find Full Text PDFApplication of the diastereoselective photodeconjugation of α,β-unsaturated esters to the synthesis of gymnastatin H.
Beilstein J Org Chem
February 2011
Université Lyon 1, UMR 5246 CNRS, Institut de Chimie et de Biochimie Moléculaire et Supramoléculaire, 69622 Villeurbanne, France.
The asymmetric synthesis of gymnastatin H has been achieved by using the photoisomerisation of a conjugated ester to its β,γ-unsaturated isomer through the protonation of a in situ generated dienol as key step. Thanks to diacetone D-glucose used as a chiral alkoxy group, the protonation occurred well onto one of the two diastereotopic faces with very high yields and selectivities. Moreover, by this way the configuration of the C-6 centre of the target molecule was controlled.
View Article and Find Full Text PDFScalable synthesis of L-iduronic acid derivatives via stereocontrolled cyanohydrin reaction for synthesis of heparin-related disaccharides.
Org Lett
October 2009
School of Chemistry and Manchester Interdisciplinary Biocentre, The University of Manchester, 131 Princess Street, Manchester M1 7DN, UK.
Article Synopsis
- L-ido cyanohydrin (3) was synthesized from diacetone-D-glucose through a four-step process, achieving a 76% overall yield and a 90% yield via the cyanohydrin reaction of aldehyde (2).
- The synthesis can be scaled up to produce more than 1 mole of pure L-ido cyanohydrin (3).
- L-ido cyanohydrin (3) was converted into various derivatives, including 1,2-isopropylidine-protected L-ido nitrile (8) and iduronic amide (9), which were then used to create new heparin-related disaccharides through coupling reactions with gluc
Want AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!