D-Mannitol 1.5- anhydro

Ana,6s (2 AM6S (where I = a-L-iduronic acid, ANA6S = 2-acetamido-2-deoxy-a-D-glucopyranose 6-sulfate, G = / -D-glucuronic acid, and AMes = 2,5-anhydro-D-mannitol 6-sulfate, the last arising from 2-deoxy-... 

Ring contraction ofglycals.1 The oxidative ring contraction of cyclic alkenes (4,492-493) can be applied to protected glycals. Thus oxidation of the D-glucal 1 with TTN in CH3CN provides the 2,5-anhydro-D-manose 2, whose structure was established by conversion to the 2,5-anhydro-D-mannitol derivative (3). 

Another example of solvolysis of a sulfonate has been described by Buchanan and coworkers 90 it occurs without acid, but utilizes a highly polarizable sulfonic ester group. Solvolysis of methyl 2-0-(p-nitrophenylsulfonyl)-a-D-glucopyranoside (84) in water in the presence of sodium acetate for 6 hours at 100° leads, after reduction of the reaction mixture by means of sodium borohydride, to a fraction identified as 2,5-anhydro-D-mannitol (85). This reaction, which... 

The competitive inhibition of aldolase by a number of structural analogs of D-ftuctose 1,6-diphosphate has been investigated.120 Among these analogs were 1,4-anhydro-DL-ribitol 5-phosphate, 1,4-anhydro-DL-xylitol 5-phosphate, 1,4-anhydro-D-arabinitol 5-phosphate, 2,5-anhydro-D-mannitol 1,6-diphosphate, and 2,5-anhydro-D-glucitol 1,6-diphosphate. Their respective, enzyme-inhibitor,... 

Glucitol ("sorbitol") is converted at the initial rates of 0,135 x 10"4mol.min g cai.at 493 K and 8,8 x 10 mol.min g cat. at 533 K. The main path is its cyclization into, first, 1,4-anhydro-D-glucitol and then to 1,4-3,6-dianhydro-D-glucitol (isosorbide) (figure 1). Two secondary ways of conversion are observed leading to 2,5-anhydro-L-iditol and 2,5-anhydro-D-mannitol. 

Both 2,5-anhydro-D-mannitol and 2,5-anhydro-D-glucitol contain the requisite 1,4-anhydro-D-arabinitol ring system.215-240 The D-mannitol derivative is about 3.5 times as potent an inhibitor as the D-glucitol derivative, perhaps by virtue of the fact that it may bind to con A either through the hydroxyl groups at C-l, C-3, and C-4, or C-3, C-4, and C-6 (compare Ref. 429). Finally, the important observation that methyl a-and /3-D-fructofuranoside are inhibitors (the (3 anomer being approximately three times as active as the a anomer) provides an explanation for the interaction of con A with plant and bacterial levans120-215-364 (see Section II,l,h). 

The formation of alditols in eye lenses is one of the major complications in diabetic patients. Interestingly, the detailed molecular pattern of the lens alditols allows us to differentiate between the diabetic lens having increased concentrations of sorbitol 3-phosphate and fructose 3-phosphate, and the galactosemic lens, where the major products are galactitol 2-phosphate and galactitol 3-phosphate [202]. 2,5-Anhydro-D-mannitol is an analogue of fructose that has become popular in cellular metabolic studies using perfused rat liver [203]. 

The inclusion of Frechet-type dendrons around stereogenic cores such as (3/v ,4.S, 5A )-3,5-dihydroxy-4-hydroxymethyl-2,2-dimethylhexane,288 289 (1 / , 2 S) -2-amino-l-phenyl- 1,3-propanediol,290 2,5-anhydro-D-mannitol,291 and TADDOL292 produced the opposite effect. As the generation number of the attached dendrons increased, the molar optical rotation of these materials generally decreased. This trend is believed to result from perturbation of the chiral conformation by the bulky dendrons.86... 

Iduronate 2-sulfate sulfohydrolase 0-(a-L-idopyrano-syluronic acid 2-sulfate)-(l— 4)-2,5-anhydro-D-mannitol 6-suIfate 4.0 0.01 1.0... 

Anhydro-D-glucitol, 2,5-anhydro-D-mannitol and their 6-phosphate and... 

Scheme 7). All the partially methylated and ethylated 1,5-anhydro-D-mannltol acetates expected from reductive cleavage-acetylation of permethylated or perethylated D-mannans have been synthesized by standard procedures and their mass spectra recorded. Application of the method to fructans revealed that 1,2-linked D-fructofuranosyl units gave mainly a 2,5-anhydro-D-mannitol derivative, while 2,6- and 1,2,6-llnked units gave mainly... 

Deamination of N-deacetylated glycosamino-glycans followed by sodium borodeuteride reduction led to pseudo-disaccharides of 2,5-anhydro-D-mannitol or -D-talitol (from D-glucosamine and D-galact-osamine residues respectively) with attached glucuronic acid,... 

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