Allitol oxidation

An amount of 16 g. of the glycol (m. p. 18°) dissolved in 250 ml. of water was oxidized with 18 g. of silver chlorate and 0.3 g. of osmic acid. The reaction mixture yielded 3 g. of allitol and no D,L-mannitol. We may therefore assign the meso configuration to the divinylglycol melting at 18°, since on hydroxylation it yielded allitol, but not D,L-mannitol. 

The effect of an ally lie hydroxy group was first observed in divinylglycol (1,5-hexadiene-cA-3,4-diol and 1.5-hexadiene-/raw.v-3,4-diol). It was shown that the hydroxy substitutions directed the addition of the osmium tetraoxide to syn addition, so that the cA-diol yielded allitol (all cA-hexaol) and the iraws-diol yielded mannitol42. The oxidation of the dienol 35 yielded a lactone ring 36 by cA-dihydroxylation and transesterification... 

Upon application of these principles to the biochemical oxidation of allitol (XII), it becomes apparent that L-psicose (XIII) would be the product expected with A. suboxydans and indeed this enantiomorph is the one that was obtained using A. xylinum. 

L-Allulose (LXI) was prepared by Steiger and Reichstein through the oxidative fermentation of allitol (LX) by the sorbose bacterium, Acetobacter xylinum. The product was isolated and purified by means of its crystalline diacetone derivative, of m. p. 57° and - -99 in... 

L-Allulose (LXI) was prepared by Steiger and Reichstein through the oxidative fermentation of allitol (LX) by the sorbose bacterium, Acetobacter xylinum. The product was isolated and purified by means of its crystalline diacetone derivative, of m. p. 57° and [a]o +99° in acetone. To the latter compound was assigned the l,2 3,4-diisopropyl-idene-L-allulofuranose structure LXII because it could be oxidized by alkaline permanganate to a crystalline uronic acid (LXIII) which, from its behavior, must have the carboxyl group in the 6- and not the 1-position. After removal of the isopropylidene groups from LXII, the free sugar, L-allulose (LXI), was obtained as a colorless sirup with — 3.3° in water. It is not fermented by yeast. 

DL-Mannitol (a-acritol) has been obtained by the reduction of a-acrose (see p. 104). Divinylglycol from acrolein was the starting point of Lespieau and Wiemann (4S). The glycol was obtained from acrolein by reduction with the zinc-copper couple and was then oxidized with silver chlorate and osmium tetroxide to DL-mannitol. Allitol was obtained simultaneously. It is apparent, therefore, that this divinylglycol must be a mixture of diols in which the hydroxyls are cis and trans. 

The diolization of the double bond in this series of reactions appears to be analogous to the diolization of the double bond of conduritol, a cyclohexene-tetrol (see Cyclitol section). When the hexenetetrol above was oxidized directly, the hydroxyls entered cis to the hydroxyls already present and allitol was the chief product similarly, aHo-inositol was obtained on oxidation of o-isopropylideneconduritol diacetate with potassium permanganate. On the other hand, for the two fully acetylated tetrols (acyclic and cyclic), the hydroxyls entered trans to those already present, giving galactitol and mwco-inositol tetraacetate, respectively (p. 284). 

CIS hydroxyls was obtained, which on oxidation with the silver chlorate-osmic acid reagent gave allitol with but a trace of galactitoL... 

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