Neuraminic acid derivative

Figure 10.7 Neuraminic acid derivatives accessible by NeuA catalysis, including an intermediate for alkaloid synthesis.

C-6,209,214 anhydro sugars,branched monosaccharides, fluori-nated amino sugars,difluorinated monosaccharides, and fluorinated monosaccharide phosphates,and phosphonates have been described. Further progress has been achieved in the synthesis and n.m.r.-spectral analysis of fluorinated avermectin Bu, tylono-lide, and neuraminic acid derivatives. " ... 

A synthetic neuraminic acid derivative having a methyl ether group at 0-4 (Neu5Ac4Me) was synthesized by Beau and coworkers101,102 by using an oxymercuration-demercuration reaction.103 The metabolic behavior of this compound will be described in Sections V and VI. 

M.-J. Kim, W. J. Hennen, H. M. Sweers, and C.-H. Wong, Enzymes in carbohydrate synthesis 79-Acetylneuraminic acid aldolase catalyzed reactions and preparation of 7V-aceiyl-2-deoxy-D-neuraminic acid derivatives, J. Am. Chem. Soc. 770 6481 (1988). 

The 4 9-bis-0- and 4>8,9-tris-0-t-butyldimethyl-silylether derivatives 2J and 8 of the biologically important neuraminic acid represent useful starting points for the synthesis of the new structurally varied nonulosonic acid derivatives 2 9 (figure 3) j5C and 21 (figure 6). Opening of the oxirsne ring of 29 with Hl. j leads to the 8-d.esoxy-8-azido-neuraminic acid derivative which corresponds completely 23. 

The use of chiral 1-oxa-l,3-butadienes for the stereoselective preparation of carbohydrates has also been investigated by Schmidt et al. [479]. The elegant syntheses of N-acetyl-/J-D-neuraminic acid derivatives are an impressive result of these studies [480]. 

C. Syntheses of Neuraminic Acid Derived Amino Acids... 

Scheme 27. Synthesis of a N-acetyl neuraminic acid derivative...

Hydrolysis of Sialic Acid (Neuraminic Acid) Derivatives... 

The oceurrence of this neuraminic acid derivative (Table 1) has first been described in cerumen of men [37], although its origin in this material remained unknown. Some hints to the possible enzymatic formation (by microorganisms ) come from the discovery... 

In an extension of the previous work [91] Takahashi and co-workers utilized the above procedure for the preparation of KDN and Neu5Ac [92]. In both these syntheses a sugar derived heptosyl bromide 84 was taken as a substrate (Scheme 21). It was reacted with cyanoacetate leading to Z-olefm 85. Stereo- and regioselective functionalization of the double bond in alcohol 85 via oxirane intermediate, and the introduction of acetamido group through trichloroacetimidate furnished 87, transformed into neuraminic acid derivative according to the previously described procedure. 

Influenza virus a- and j8-Ketosides of neuraminic acid derivatives Sepharose 4B 208... 

A careful investigation has been performed on the m.s. of per(tri-methylsilyl) ated neuraminic acid derivatives. " The study demonstrated that m.s. can be a valuable tool for the characterization of these compounds. 

When the neuraminic acid derivative 52 was treated with diethylamine, selective S-deacetylation occurred, and the deacetylated material could be alkylated with various 6-bramo-6-deoxyhexose derivatives to give thioglycoside disaccharides.5i... 

Figure 3.251 Separation of neuraminic acids derived from glycoproteins. Separator column CarboPac PA10 eluent (A) 0.1 mol/L NaOH, (B) 0.1 mol/L NaOH+ 1 mol/L NaOAc gradient linear, 7% B to 30% B in 10 min flow rate ...

Fig. 3-192. Separation of neuraminic acids derived from glycoproteins. - Separator column CarboPac PAIO eluant ...

Neuraminic acid derivatives newly discovered in humans A/-acetyl-9-0-lactoylneuraminic acid, N,9-0-diacetylneuraminic acid and A/-acetyl-2,3-dehydro-2-deoxyneuraminic acid. Hoppe-Seylers Zeitschrift Fur Physiologische Chemie, 357, 1699-1705. 

The 4- and 7-oxo-Macetylneuraminic acid derivatives (7) and (8) have been synthesized. Treatment of the latter with Na2C03 afforded a 1 1 mixture of 8-oxo-neuraminic acid derivatives (9) and (10) (Scheme 3). ... 

Neuraminic acid derivatives variously N-acylated have been prepared by reduction-acylation of a 5-azido compound, itself produced from 2-azido-2-deoxy-D-mannose using NeuNAc pyruvate lyase.54... 

Neuraminic Acid Derivatives as MAG Antagonists - First Generation. 172... 

In order to explore further the substmctural determinants of sialic acid required for MAG binding, Kelm and Brossmer [28, 72], and later our group [73, 74], evaluated the inhibitory potential of simple neuraminic acid derivatives towards MAG and... 

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