Sialic acid peracetylated

G. P. Smirnova, N. V. Chekareva, O. S. Chizhov, B. M. Zolotarev, and N. K. Kochetkov, Mass spectrometry of sialic acids Peracetylated methyl esters of 5-acylamino-3,5-dideoxy-nononic and -heptonic acids, Carbohydr. Res., 59 (1977) 235-239. 

Selenoglycosides of sialic acid have been successfully prepared in excellent yields from the corresponding peracetylated glycosyl chloride with phenylselenol in the presence of N,N-di-isopropylethylamine [519]. This reagent combination succeeded where others were less effective or failed (Scheme 4.98 [520]. 

Another strategy for selective delivery of CA s at cancer cells exploits the intrinsic overexpression of sialic acid in them. Upon incubation of cancer cells with peracetylated N-levulinoylmannosamine the sialoside biosynthetic pathway affords N-levulinoyl sialic acid, the ketone group of which can be a target for an Gd3+ complex of an aminooxy-functionalized DTPA derivative [165]. 

Preparation of fructose dithioacetals involves the keto peracetate 6.3 which is the normal peracetylation product. However, the carbonyl group of sialic acid is transformed into diethyl dithioacetal 6.4 in excellent yield at room temperature. The a-carboxyl and lactonization in this medium no doubt help in the conversion. 

Chitin deacetylase has been used in the synthesis of partially and fully N-deacetylated 4-methyl umberlliferyl chitobiose derivatives as fluorogenic substrates for chitinase. Conversely, the reverse acylating action of chitin deacetylase has been used to prepare a partially N-acetylated chitosamine tetramer. The preparation of a 4-0-acetyl sialic acid derivative by a lipase OF-catalysed deacetylation of the peracetylated precursor has been reported. ... 

Modified with peracetylated iST-azidoacetylmannosamine (Ac ManNAz) was added to CHO cell lines containing the recombinant glycoprotein GlyCAM-Ig, and this resulted in metabolic incorporation of the corresponding N-azidoacetyl sialic acid into its glycans. 

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