Related Experiment Video
Updated: Aug 18, 2026

Metabolic Glycoengineering of Sialic Acid Using N-acyl-modified Mannosamines
Published on: November 25, 2017
Alpha-N-acetylmannosamine (ManNAc) synthesis via rhodium(II)-catalyzed oxidative cyclization of glucal 3-carbamates
Rena Bodner1, Bridget K Marcellino, Alexandra Severino
1Department of Chemistry, Barnard College, 3009 Broadway, New York, New York 10027, USA.
Abstract:
[reaction: see text] Glucal 3-carbamates 1 and 7 underwent oxidative cyclization with iodobenzene diacetate or iodosobenzene in the presence of Rh2(OAc)4, providing mannosamine 2-N,3-O-oxazolidinones. With iodosobenzene, incorporation of 4-penten-1-ol provided a readily separable anomeric mixture of n-pentenyl glycosides, with the anomers exhibiting pronounced differences in reactivity as glycosyl donors. N-acylation of the sugar oxazolidinones led to alpha-selective glycosyl donors for the elaboration of various 2-mannosamine frameworks. Alternatively, the anomeric n-pentenyl glycosides of N-Cbz 2-mannosamine oxazolidinones were converted separately to oxazolidinone-opened derivatives 28alpha and 28beta. These served as stereoconvergent glycosyl donors, and the alpha-linked products were readily advanced to a variety of N-acetylmannosamine (ManNAc) frameworks, using an intramolecular O-->N acetyl transfer as the final step.
More Related Videos
06:46Facile Preparation of (2Z,4E)-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
08:46Regioselective O-Glycosylation of Nucleosides via the Temporary 2',3'-Diol Protection by a Boronic Ester for the Synthesis of Disaccharide Nucleosides
Published on: July 26, 2018
Related Concept Videos
Cyclohexenones via Michael Addition and Aldol Condensation: The Robinson Annulation
Preparation of 1° Amines: Gabriel Synthesis
Strong bases like NaOH or KOH deprotonate the phthalimide to form the corresponding anion, which acts as a nucleophile. Further, the anion attacks an...
Acid-Catalyzed α-Halogenation of Aldehydes and Ketones
In the first step of the mechanism, the acid protonates the carbonyl oxygen resulting in a resonance-stabilized cation, which subsequently loses an α-hydrogen to form an enol tautomer. The C=C bond in an enol is highly nucleophilic because of the electron-donating nature of the –OH group. Consequently, the double bond attacks an electrophilic halogen to form a...
Preparation of Amines: Reductive Amination of Aldehydes and Ketones
Preparation of 1° Amines: Hofmann and Curtius Rearrangement Overview
Preparation of 1° Amines: Hofmann and Curtius Rearrangement Mechanism