9-O-acetylneuraminate

Sialyl residues in oligosaccharides are introduced by the reaction of cyti-dine monophosphate-V-acetylneuraminic acid (49) as the sugar donor with the appropriate substrate, in the presence of specific transferases. Three of these have been utilized in syntheses which may be considered to be preparative. None are readily available. The most common, which we have called STA (see Table I), catalyzes the transfer of a 5-acetamido-3,5-di-deoxy-D-g/ycm>-a -D-ga/arfo-2-hexulopyranosonic acid unit (the a-D-pyra-nose form of JV-acetylneuraminic acid) to the primary position of D-galactose in a JV-acetyllactosamine residue.86 This enzyme also transfers vV-acetyl-9-O-acetylneuraminic acid (20) and V-glycolylneuraminic acid (12) from the corresponding cytidine monophosphate derivatives.16 The commercial enzyme is rather expensive, but pork liver from a butcher is a... 

The preparation of trisaccharide 63 illustrates the activation and enzymic coupling of the 9-acetate of vV-acetylneuraminic acid, This involves the utilization of enzymes in a cascade of reactions which probably do not occur in cells (a) synthesis of Neu5,9Ac2 from the 6-acetate of vV-acetylmannosa-mine with the catabolic sialyl aldolase, (b) activation with CMPNeu5Ac synthetase, and (c) coupling. Acetylation in cells seems posterior to coupling. Terminal nonreducing vV-acetyl-9-O-acetylneuraminic acid residues appear... 

C. Augd, S. David, C. Gautheron, and A. Veyrieres, Synthesis with an immobilized enzyme of iV-acetyl-9-O-acetylneuraminic acid, a sugar reported as a component of embryonic and tumor antigens. Tetrahedron Lett. 26 2439 (1985). 

Harms, G., Reuter, G., Corfield, A.P., and Schauer, R. Binding specificity of influenza C-virus to variably O-acetylated glycoconjugates and its use for histochemical detection of iV-acetyl-9-O-acetylneuraminic acid in mammalian tissues. Glycoconj. J. (19%) 13, 621-630. 

A-acetylneuraminic acid A-acetyl-4-O-acetylneuraminic acid A-acetyl-7-O-acetylneuraminic acid A-acetyl-8-O-acetylneuraminic acid A-acetyl-9-O-acetylneuraminic acid /V-acetyl-4,9-di-0-acetylneuraminic acid A-acetyl-7,9-di-0-acetylneuraminic acid A-acetyl-8,9-di-(9-acetylneuraminic acid A-acetyl-7,8,9-tri-0-acetylneuraminic acid A-acetyl-9-0-acetyl-8-0-methylneuraminic acid A-acetyl-9-O-lactoylneuraminic acid A-acetyl-4-0-acetyl-9-(7-lactoylneuraminic acid A-acetyl-8-0-methylneuraminic acid A-acetylneuraminic acid 9-phosphate A-acetylneuraminic acid 8-sulfate 2-deoxy-2,3-didehydro-A-acetylneuraminic acid 2-deoxy-2,3-didehydro-A-acetyl-9-(9-acetylneuraminic acid 2-deoxy-2,3-didehydro-A-acetyl-9-(9-lactoylneuraminic acid 2,7-anhydro-A-acetylneuraminic acid ... 

Munoz-Barroso, I., Garcia-Sastre, A., Villar, E., Manuguerra, J. C., Hannoun, C., and Cabezas, J. A., 1992, Increased influenza A virus sialidase activity with N-acetyl-9-O-acetylneuraminic acid-containing substrates resulting from influenza C virus O-acetylesterase action. Virus Res. 25 145-153. 

The structure of a novel L-fucose-containing ganglioside from pig cerebellum has been established (2). 9-O-Acetyl-A-acetylneuraminic acid accounts for up to 20% of the brain ganglioside fractions from man, cow, horse, pig, sheep, cat, rabbit, rat, chicken, and codfish. In the pig and cow, traces of the A-glycolyl derivative were also found. The novel trisialoganglioside, Giia (3), has been isolated and characterized and is responsible for 0.6% of the total ganglioside fraction of human brain. ... 

Rogers GN, HottIct G, Paulson JC, Klenk HD (1986) Influenza C virus uses 9-O-acetyl-iV-acetylneuraminic add as a high affinity receptor determinant for attachment to cells. J Biol Chem 261 5947-5951... 

The periodate oxidation of 9-O-acetyl and 4,9-di-O-acetyI derivatives of the methyl ester of 7V-acetyl-)8-D-neuraminic acid methyl glycoside has been studied the 9-O-acetyl group was found to hinder the oxidation, thus accounting for the low molar absorbancy coefficient of such derivatives in the periodate-thiobarbituric acid assay. The reactivity of a seven-carbon analogue of AT-acetylneuraminic acid, namely 5-acetamido-3,5-dideoxy-L-ara //io-heptulosonic acid, in the thiobarbituric acid and resorcinol assays has also been evaluated and the formation of the various chromophores discussed. ... 

The predicted results outlined in Fig. 4 are based upon the assumption that the C9 class of sialic acids is completely oxidized under the conditions employed in the PAT/KOH/PAS and PBT/KOH/PAS procedures. Haverkamp et al. (1975) showed that the oxidation of 9-O-acetyl-N-acetylneuraminic acid and its methylglycoside, with limited quantities of periodate, was very much slower than the oxidation of N-acetylneuraminic acid and its glycoside. Should this phenomenon occur under the very different conditions used in histochemistry, then some, or all, of any Cp class of sialic acids would be identified as members of the Cg class of sialic acids. 

N- Acetyl-7,8-di-O-acetylneuraminic acid or N-Acetyl-7,9-di-O-acetyIneuraminic acid 5- Acetamido-7,8(or 7,9)-di-0-acetyl-3,5-dideoxy-D-g/y-cero-D-galacto-nonu osonic acid C15H23NO11... 

N-Acetyl-4,9-di-O-acetylneuraminic acid" 5-Acetamido-4,9-di-0-acetyl-3,5-dideoxy-D- /ycero-D-g /flc o-nonulosonic acid C15H23NO11... 

The sialic acids whose structures were recently questioned by the above mass spectral data are indicated in Table I according to both the original and new assignments. In support of the revised structures, synthetic 9-0-acetyl derivatives were shown to react slowly with periodate comparable to the naturally occurring sialic acids (Haverkamp et al., 1975). Thus far no reports have appeared concerning the location of acetyl groups on the )V-acetyl-tri-0-acetylneuraminic acid (7) obtaind from bovine submaxillary mucin. Very recently a new sialic acid was discovered (Schauer et al., 1976) in bovine submandibular gland N-aceytl-9-O-L-lactylneuraminic acid (II). 

Derevitskaya, V. A., Kalinevich, V. M., and Kochetkov, N. K., 1965a, Synthesis of methyl ester of 9-O-glycyl-A-acetylneuraminic acid, Dokl. Akad. Nauk SSSR 160 5%. 

At least two species of sialic acid, V-acetyl- and N-glycolylneura-minic acids, have been identified in poultry serum, together with a very small amount of a third species, possibly A, 0-diacetylneuraminic acid (Faillard and Cabezas, 1%3 Dzulynska f u/., 1%9). The nest-cement-ing substance of the Chinese swiftlet, collocalia mucoid, is a glycoprotein containing V-acetyl-4-O-acetylneuraminic acid (Kathan and Weeks, 1969). 

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