Idose

Once the eight Fischer projections have been written they are named m order with the aid of the sentence All altruists gladly make gum m gallon tanks The words of the sentence stand for allose altrose glucose mannose gulose idose galactose talose... 

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... 

The aldohexoses are allose, altrose, glucose, mannose, gulose, idose, galactose, and talose. The mnemonic All altruists gladly make gum in gallon tanks is helpful in writing the conect Fischer projection for each one. 

D-Allose D-Altrose D-Glucose D-Mannose D-Gulose D-Idose D-Galactose D-Talose... 

Problem 25.22 What aldopentose would give a mixture of L-gulose and L-idose on Kiliani-Fischer chain extension ... 

When heated to 100 CC/ D-idose undergoes a reversible loss of water and exists primarily as 1,6-anhydro-n-idopyranose. 

L-idose 293, 311 ff. imine formation 57 imine-enamine tautomerization 467 iminium-RhH jt complex 351 f. imipenem 348 indoline ligands 681, 684 indolizomycin 47 Iff. -.retrosynthetic analysis 472ff. 

DDDU initial idose, then 5DDDU every 8-12 hours X 7 days 40 mg once daily x 7-10 days... 

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... 

C13-0015. Describe the differences in the structures of a-glucose and a-idose, a rare naturally occurring monosaccharide. 

The identification of L-iduronic acid as the major glycuronic acid constituent of heparin proved to be a much slower process than the identification of the amino sugar residue. Although this compound was detected in acid hydrolyzates of heparin116117 and heparin oligosaccharides,118 its yield was usually poor, because of the drastic conditions used for the acid hydrolysis (which are known to lead to extensive destruction of uronic acid).119120 Also, L-iduronic acid escaped detection as L-idose in the hydrolyzates of carboxyl-reduced heparin, probably because L-idose is readily converted into 1,6-anhydro-L-idose under the usual hydrolytic conditions. 

Examination of early -n.m.r. spectra of heparin and of chemically modified heparins121 prompted a reinvestigation of N,0-desulfated, carboxyl-reduced heparin, leading to the isolation of substantial amounts of L-iditol pentaacetate.121,122 In addition, improved conditions for the acid hydrolysis of heparin and carboxyl-reduced heparin gave increased recoveries of L-iduronic acid and 1,6-anhydro-L-idose, respectively.123 These findings confirmed the L-enantiomeric designation of the iduronic acid, and established that it is the main uronic acid in heparin. 

Some examples will illustrate the applicability of this generalization in so far as it concerns alkaline scission. 5,6-Anhydro-l,2-isopropylidene-D-glucofuranose with alcoholic sodium hydroxide gives a mixture of isopropylidene-D-glucose and isopropylidene-L-idose. The latter results from inversion on C5, the former presumably by inversion on the non-asymmetric C6.7 3,4-Anhydro-l,2-isopropylidene-D-psicose (or allu-lose17) (XX) when treated with sodium hydroxide yields a mixture of products among which 1,2-isopropylidene-D-fructose (XIX) was detected (in the representations inversions are denoted by circles above the arrows and the carbons inverted are noted below the arrows). With sodium methoxide, however, l,2-isopropylidene-4-methyl-D-sorbose (XXI) is the chief product and results from inversion on C4.1S... 

Acetolysis of LXXIV gives, as might be expected, a mixture of the acetates of n-mannose and D-idose and as the dianhydro sugar has a free hydroxyl on C2, it should prove to be a source of 2-substituted n-mannose or D-idose and of 2,4-derivatives of n-mannose and 2,3-derivatives of D-idose. 

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