Lyxitol 2.5- anhydro

In a detailed study of the deamination of the four 1-amino-1-deoxy-D-pentitols (109-112), the products were analyzed by g.l.c. It was found that each aminodeoxypentitol gives three products in differing ratios.202 In addition to the pentitol and the corresponding 1,4-anhydropentitol, there is formed a second 1,4-anhydropentitol. The latter was found to be formed by ring closure between the 5-hydroxyl group and C-2, with inversion at C-2. For example, 1-amino-1-deoxy-D-lyxitol gives 1,4-anhydro-D-lyxitol, 2,5-anhydro-D-xylitol (= 1,4-anhydro-L-xylitol), and D-lyxitol. Because the second 1,4-... 

Cleavage of the dithioacetal groups from the products, followed by reduction of the resultant carbonyl derivatives (46, 49, 52) with sodium borohydride leads,68 with the three compounds (45, 48, and 51), to 1,4-anhydro-L-ribitol (2,5-anhydro-D-ribitol) (47), 1,4-anhydro-L-xylitol (2,5-anhydro-D-xylitol) (50), and 1,4-anhydro-D-arabinitol (2,5-anhydro-D-lyxitol) (53), identified by comparison with their enantiomorphs, 1,4-anhydro-D-ribitol,69 1,4-anhydro-D-xylitol,70 and 1,4-anhydro-L-arabinitol. 71... 

In contrast to ribitol and xylitol (which form a dl mixture on anhydride formation because of their molecular symmetry), D-arabinitol may, in principle, on heating with acid, give two different anhydrides, namely, a 1,4-anhydroarabinitol ora 2,5-anhydroarabinitol (1,4-anhydro-lyxitol), as the following reaction sequence illustrates. 

The enantiomorph, also a syrup, was synthesized from 3,6-anhydro-4,5-O-isopropylidene-D-mannitol18 by periodate oxidation to the corresponding D-arabinose derivative, followed by reduction in the presence of Raney nickel.17 2,5-Anhydro-D-xylitol, 2,5-anhydro-D-ribitol, and 2,5-anhydro-D-lyxitol (1,4-anhydro-D-arabinitol)19,20 were... 

Defaye19 called attention to the fact that the 2,5-anhydro-tri-0-(p-nitrobenzoyl)-D-lyxitol that he prepared is the enantiomorph of Barker and Fletcher s 1,4-anhydro-tri-0-(p-nitrobenzoyl)-L-arabinitol.l4alditol anhydrides derived, without Walden inversion, from two configurationally different sugars have been shown experimentally to possess the same, although enantiomorphic, configuration. 

D-arabinitoI (160a), 1,4-anhydro-L-ribitol (161), 1,4-anhydro-L-lyxitol (162), an arabinitol, and ribitol. Tetra-0-acetyl-l,4-anhydro-D-gIucitoI likewise reacts unpredictably in hydrogen fluoride the products found after hydrolysis were 1,4-anhydro-D-gIucitoI, 1,4-anhydro-D-mannitoI, galactitol, D-glucitoI, an iditol, and a mannitol. ... 

Tribenzoyl 2,5-Anhydro-l,3,4-tri-0-ben-zoyl-D-arabinitol. 1,4-Anhydro-2,3,5-tri-0-benzoyl-D-lyxitol C26H22O7 446.456... 

Anhydro-l-deoxy-D-lyxitol, -mannitol, and -talltol have been synthesized and examined as substrates and Inhibitors of hexo-... 

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