Idose 6-deoxy

Most substrates, with the exception of hydroxypymvate, have a threo configuration of hydroxyl groups at the C-3 and C-4 positions (139). The new stereocenter formed in TK-catalyzed addition is formed in the threo configuration with high diastereo-selectivity (151). Using TK-catalyzed condensations of hydroxypymvic acid with a number of aldehydes a practical preparative synthesis of L-idose [5934-56-5], L-gulose [6027-89-0], 2-deoxy-L-xylohexose, and... 

Deoxy-5-fluoro-D-glucose and -L-idose were synthesized from 1,2-(9-isopropylidene-a-D-glucofuranurono-6,3-lactone (285). Treatment of l,2-0-isopropylidene-5-0-triflyl-a-D-gluco- (286 prepared from 285) and -) -L-ido-furanurono-6,3-lactones (289 prepared from 288), with BU4NF... 

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. 

The difference between the behavior of the 6-amino-6-deoxy-D-glucose and -L-idose derivatives can be rationalized as follows. In the transition states for the formation of the 3,6-anhydro ring from the Tt-gluco isomers, the oxygen (or hetero) atoms attached to C-4 and C-5 are in a sterically unfavorable, cis relationship. The transition states from the h-ido amines involve a trans relationship of these hetero atoms. Thus, for the D-gluco amine, deamination reactions other than 3,6-anhydro ring-formation compete more effectively. 

M. L. Wolfrom and S. Hanessian, The reaction of free carbonyl sugar derivatives with organo-metallic reagents. I. 6-Deoxy-L-idose and derivatives, J. Org. Chem. 27 1800 (1962). 

Gross and Oriez125 reported the synthesis of 4-S-acetyl-6-deoxy-4-thio-D-altrose (302) and 4-S-acetyl-6-deoxy-4-thio-D-idose (303) by using, as starting materials, the corresponding thiocyanates prepared in 35% yield from the 4-O-mesyl derivatives 298 and 299 by Sn2 displacement with thio-... 

As found typically for glucose and idose, nearly equal proportions of the two furanose forms were observed39 for 5-deoxy-5-fluoro-D-glucose (45 55) and -L-idose (47 53). 

O-Isopropylidene-l,0-di-O-tosyl-D-fructose 6-Deoxy-2,3-0-isopropyIidene-l-0-tosyl-D-fructose 5,6-Anhydro-l,2-0-isopropyIidene-3-0-tosyl-L-idose... 

Pyranoid compounds such as 252 undergo hydroboration and hydrogenation to give mixtures of D-glucose and L-idose derivatives and their 6-deoxy analogues, respectively, the ratios depending on reaction conditions and on structural details of the substrates. Acid-catalyzed hydrolysis leads to 6-deoxyaldos-5-uloses.6... 

Idopyranoside, methyl 4,6-0-benzyli-dene - 3 - 0 - (ethoxycarbonyl) - 2 - S-methyl-2-thio-a-D-, 120 Idose, 2-amino-2-deoxy-n-, derivatives of, 194... 

The study was intended to prove the intermediacy of nitroalkene 8 in the unexpected deacetona-tion-methoxylation of 1,2 3,5-diisopropylidene-6-deoxy-6-nitro-a-n-glucofuranose(ll), which occurred upon treating the latter carbohydrate with dilute methanolic sodium hydroxide60. In this reaction, deacetylated 9 and 10 were formed in a 4 1 ratio, too. Interestingly, under identical conditions, the cpimeric L-idose 12 was reversibly deprotonated and did not lose acetone. 

Another route to 5-amino-5-deoxy-L-idose proceeds from 5-(benzyl-amino)-5-deoxy-l,2-0-isopropylidene-R-L-idurononitrile (56), which is readily obtainable from 1,2-O-isopropylidene-a-D-xj/lo-pentodialdo-1,4-furanose (13) by reaction with benzylamine and hydrogen cy-anide. Partial hydrogenation of the nitrile 56 by the Kuhn procedure, in acid solution, leads to the hexodialdose (57), which is reduced with sodium borohydride to 5-amino-5-deoxy-l,2-0-isopro-pylidene-jS-L-idofuranose. From this compound, tbe acyclic bisulfite adduct (58) is obtained by reaction with sulfiirous acid. Treatment of 58 with barium hydroxide gives crystalline 5-amino-l,6-anhydro-5-deoxy-jS-L-idopyranose (60) in almost quantitative yield. The equilibrium between the pyranose form (61) and its 1,6-anhydride (60) lies far on the side of Ae bicyclic form (60). The equilibrium can be evaluated from the optical rotation of the solution obtained by treat-... 

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