6-Deoxy-L-altrose

Such a situation is rather common for D-galactose and the structurally related monosaccharides L-arabinose218 and D-fucose thus far, the latter monosaccharide has been identified only as the furanose form in the O-specific polysaccharide of Eubacterium saburreum.219 6-Deoxy-L-altrose is present as the pyranose in the lipopolysaccharide of Yersinia enteroco-litica,20 but as the furanose in a similar polymer220 of Y. pseudotuberculosis type VB. Paratose, which is usually present in polysaccharides as the a-pyranose, was identified as the /3-furanose in the O-specific polysaccharide221,222 of Y. pseudotuberculosis serotype IB. 

Occurrence and preparation. 6-Deoxy-L-altrose (34) is a monosaccharide occurring rarely in Nature. 6-Deoxy-L-altropyranose forms homopolysaccharide O-chains in LPSs of some Yersinia enterocolitica serovars.164 6-Deoxy-L-altrofuranose is one of the constituent monosaccharides of an O-specific polysaccharide of Y. pseudotuberculosis serovar VB165 and was also found in a polysaccharide from Campylobacter jejuni 176.83 (serotype 0 41) that contains only furanose sugars.30 A homopolymer of 6-deoxy-L-altrofuranose has been found in the LPS of Pectinatus frisingensis,166 which is in turn the source for the isolation of this sugar. 

A number of 6-deoxyhexoses also are widespread in plants, but these compounds are especially common in cardiac glycosides (Courtois and Percheron, 1970). These sugars are formed from the corresponding hydroxylated monosaccharides (Luckner, 1990). Among the 6-deoxyhexoses are L-acofriose (6-deoxy-3-0-methyl-L-mannose) (18), l-acovenose (6-deoxy-3-6>-methyl-L-talose) (19), o-allometh-ylose (6-deoxy-D-allose) (20), L-altromethylose (6-deoxy-L-altrose) (21), D-antiarose (6-deoxy-o-gulose) (22), D-boivi-nose (2,6-dideoxy-D-xy/o-hexose) (17), D-cymarose (2,6-di-... 

Deoxy-p-L-altropyranosyl- D-36 (1 ->2)-6-deoxy-p-L-altropyranosyl-b ->3)-6-deoxy-L-altrose, 9CI... 

Deoxy-p-L-altropyranosyl-(l 2)-6-deoxy-p-L-altropyranosyl-(l 3)-6-deoxy-L-altrose p-Pyranose-/orm, D-36 6-Deoxy-p-L-altropyranosyl-(l 2)-6-deoxy-p-L-altropyranosyl-(l 3)-6-deoxy-L-altrose, D-36 6-Deoxyaltrose D-form, D-37... 

Deoxyketoses are of rare natural occurrence. The antibiotic hygromycin177 has been shown to contain 6-deoxy-D-arabmo-hexos-a-ulose residues, since reduction of the free sugar gave 6-deoxy-D-altrose and L-fucose. Yungsten and coworkers171 reported the isolation of a 6-deoxy-L-x2/io-hexulose (an-gustose) from the antibiotic Angustmycin A, for which structure (37) was proposed. 

Ionophoresis of Carbohydrates. Part VII. 2,5-Di-O-methyl-L-rhamnose Its Ionophoresis and Conversion into 6-Deoxy-2 5-di-0-methyl-L-altrose, A. B. Foster, J. Lehmann, and M. Stacey, /. Chem. Soc., (1961)4649-4653. 

Nativi, C, Reymond, J-L, Vogel, P, Acid-catalyzed rearrangement of 3-aza-8-oxatricyclo[3.2.1.0 ]octan-6-one acetals. Highly stereoselective total synthesis of 3-amino-3-deoxy-D-altrose and derivatives, Helv. Chim. Acta, 11, 882-891, 1989. 

Figure 4 Proposed biosynthetic pathway of pseudaminic acid in Campylobacter. The predicted activity of PseF (last step) is based on the homology to the corresponding enzyme (NeuA) in the sialic acid biosynthetic pathway. Pse, pseudaminic acid (5,7-diacetamido-3,5,7,9-tetradeoxy-L-glycero-L-manno nonulosonic acid) Alt, altrose 6-deoxy-AltdiNAc, 2,4-diacetamido-2,4,6-trideoxy-L-Alt.

From Chiral Non-carbohydrates - A section on amino-sugars has been included in a review of the synthesis of monosaccharides from non-carbohydrate sources. L-Ristosamine 42 was synthesized by addition of the Cs-synthon 40 (which contains a masked aldehyde function that can be readily demasked by mild acid hydrolysis) to the L-lactaldehyde derivative 41 (Scheme 11). The TBSOP adduct 43 (Vol.27, p.ll4), derived from 2,3-< -isopropylidene-D-glycer-aldehyde, has been converted into 3-amino-3-deoxy-D-altrose 46 by a route involving cis-hydroxylation of its unsaturated lactam moiety and periodate cleavage between C-6 and C-7 of the derived heptitol derivative 45 as key steps (Scheme 12). 3-Amino-3-deoxy-L-allose was obtained by converting 43 to its C-3... 

Deoxyaltrose L-form, D-37 6-Deoxy-3-0-methylaltrose Lrform, D-292 6-Deoxy-4-0-methyl-D-altrose, D-37... 

A. C. Richardson and H. O. L. Fischer, Cyclization of dialdehydes with nitromethane, Part VI. Preparation of 3- amino-1,6-anhydro-3-deoxy-p-D-gulose, -P-D-altrose and -p-D-idose derivatives and their characterization by means of inversion of mesyloxy groups,./. Am. Chem. Soc., 83 (1961) 1132-1139. 

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