D-Quercitol

D-ohiro-lnositol, 2-deoxy- 2-Deoxy-D-chiro-inositol D-1-Deoxy-muoo-inositol (- )-Protoquercitol ( )-Quercitol d-Quercitol. Sugar found in aooms. Used as a chemical intermediate. Crystals mp = 234-235° 24-26° soluble in H2O, slightly soluble in hot EtOH,... 

The 1-phosphate ester of this diol is said to occur in brain tissue and sea-urchin eggs. Strong evidence that cordycepic acid is really D-mannitol. Not an enantiomorph of d-quercitol other isomeric relationship is involved. 

D-Quercitol (73) is common in members of the genus Quercus, oaks, of the family Fagaceae. This cyclitol derivative is known from at least nine other families. D-Pinitol (63) is known from six families of gymnosperms, in which it is widespread, but it is also known from a number of angio-sperms. 

Sixteen pentahydroxycyclohexanes are predicted on the basis of stereochemical theory. The configuration of d-quercitol was limited to that shown below by nitric acid oxidation to galactaric (mucic) acid (8 ) and by alkaline permanganate oxidation to 3-deoxy-D-galactaric acid (metasaccharinic acid) (83), This same acid was obtained from Z-viburnitol (58), Hence, the arrangement of hydroxyl groups on carbon atoms 2, 5, and 6 of d-quercitol and Z-viburnitol must be the same. Another series of reactions also led to identical compounds from these two deoxyinositols (53), It was found that Acetobacter suboxydans catalyzed the oxidation of Z-viburnitol to a deoxy-... 

This oxidation, as employed by Posternak, was very useful in elucidating the configuration of the inositols (see above). From mj/o-inositol, S. and T. Posternak obtained DL-talaric and DL-glucaric acids. From myo-inosose-2, T. Posternak obtained DL-idaric acid. In these instances, the ring was opened to form dibasic acids. d-Quercitol was oxidized by Posternak (6S) to 3-deoxy-D-galactaric acid. In all these oxidations, it was necessary to maintain low temperatures. 

There appears to be only one example of halohydrins obtained by direct action of halogen acids on the cyclitols d-quercitol was heated at 100° with a solution of HCl (saturated at 10°), and a very small amount of substance, m.p. 198-200°, was obtained which had an analysis corresponding to a monochlorohydrin 100) and also one, m.p. 155°, that appeared to be a trichlorohydrin, C6H7Cl3(OH)2. 

There is only one instance in the literature of the preparation of a di-cyclitol ether. This was obtained by Prunier 100) by heating d-quercitol at 235-250°. A compound, m.p. 228-230°, and having the composition C12H22O9, sublimed. The residual sirup contained a small amount of substance (quercitan) which may be an internal ether. 

D-Quercitol, a pentahydroxycyclohexane, is found in the bark of Quercus suber and Tiliacora acuminata and roots of Cissampelos pareira, Legnephora moorii and Cyclea burmanni (see 137). It appears to be uniformly present in the bark of oak (Quercus spp.). 

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