2,3-Dideoxy ulosonic acids

Among various modifications of KDO, 2-deoxy-P-KDO which is believed to be inhibitor of CMD-KDO synthetase has attracted great interest as a potential antibiotic [142], Another importance of 2,3-dideoxy ulosonic acids comes from the possibility of using them as the precursors of glycosyl donors. 

The hetero Diels-Alder reaction has been used to access the eight [144,147], seven [145] and nine [146,148] carbon 2,3-dideoxy-ulosonic acid skeleton in which the C-2-C-3 and C-6-0-6 bonds were created in cycloaddition step. 

Neuraminic acid for 5-amino-3,5-dideoxy-D-g/ycero-D-ga/acfo-non-2-ulosonic acid... 

Mycarose Mycinose Neuraminic acid (Neu) 2,6-D ideoxy-3- C-methy I-l- ribo- hexose 6-Deoxy-2,3-di-Omethyl-D-allose 5-Amino-3,5-dideoxy-D-g/ycero-D-ga/acfo-non-2-ulosonic acid... 

Vinogradov, E., Korenevsky, A., Beveridge, TJ. The structure of the core region of the lipopolysaccharide from Shewanella algae BrY, containing 8-amino-3,8-dideoxy-D-manno-oct-2-ulosonic acid. Carbohydr Res 339 (2004) 737-740. 

The sialic acids are a large family of mono-saccharides derived from 3-deoxy-non-2-ulosonic acid. The three major sialic acids found in nature are W-acetyl (NeuSAc) 1 and A-glycolyl (NeuSGc) 2 derivatives of neuraminic acid (5-amino-3,5-dideoxy-D-gfycero-D-.ga/acto-non-2-ulosonic acid) and KDN (3-deoxy-D- /ycero-D- a/acto-non-2-ulosonic acid) 3 (O Fig. 1)... 

Fig. 1. Chemical structures for simple sialic acids in different views, (a) S-amino-S.S-dideoxy-D-gfycero-D-ga/acro-non-2-ulosonic acid (Neu, open chain, Fischer projection formula) (b) 5-acetaraido-3,5-dideoxy-D-g/> cero-a-D-gfl/acto-non-2-ulopyranosonic acid (a-Neu5Ac, Fischer projection formula, note that C7 is the anomeric reference atom) (c) a-Neu5Ac (Haworth projection formula) (d) a-Neu5Ac ( 5 chair conformation) (e) 3-deoxy-D-g/ycero-3-D-gfl/acto-non-2-ulopyranosonic acid (P-Kdn, 5 chair conformation). Note that the D-notation is part of the trivial name.

A-Acetylneuramic acid (D-NeupAc, NN) H HO ho h 3C0CHN OH N-Acetylneuramic acid, NeuAc is 5-acetamido-3,5-dideoxy-D-glycero-D-galacto-non-2-ulosonic acid. Substituted neuramic acids are also designated as sialic acid (Sia). Sia is linked to oligosaccharide chain of N-glycoprotein via a-2—>3 and a-2 6. 

Diamino-5,7,9-trideoxynon-2-ulosonic acid, D-483 l,2-Dideoxy-2-fluoro-l,5-iminoniannitol i>-form, D-566... 

Purified bovine-liver /3-D-glucuronidase (p/5.1, mol. wt. 2.9 x 10 , pH optimum 4.4) exhibited a broad pH-activity profile and contains 6.3% of carbohydrate consisting of o-galactose (8), o-glucose (7), o-mannose (45), 2-amino-2-deoxy-D-glucose (32), and 5-acetamido-3,5-dideoxy-D- /jccro-D- a/nc/o-2-non-ulosonic acid (5 moles mol" ). ... 

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