II. CHEMISTRY 337 



296-297°; f/-inositol (VIII), m.p. 249-250°; [a]f = +65.0° (in water); 

 /-inositol (IX), m.p. 249-250°; [a]^^ = -63.8° (in water). 



The behavior of cyclohexitols toward oxidizing agents is not yet com- 

 pletely understood. Vigorous action of nitric acid, as it is employed in the 

 Scherer test for the qualitative demonstration of inositol, leads to aromati- 

 zation and a whole series of six- and five-membered polycarbonyl com- 

 pounds, such as tetrahydroxyquinone and rhodizonic, croconic, and leuconic 

 acids. Under milder conditions meso-inositol (V) is converted by nitric 

 acid to DL-2-keto-ep*-inositol (numbering as in Table I).^^ 



meso-Inositol (V) behaves in an anomalous fashion toward oxidation 

 by periodic acid.^'' Instead of the expected uptake of 6 equivalents of oxi- 

 dizing agent, only 4 equivalents are consumed in a first rapid phase, which 

 is followed by a second, much slower one. The reaction mechanism is not 

 5^et understood completely. It is the opinion of this writer, however, that 

 the spatial constellation of the hydroxyl group in a given inositol isomer, 

 as discussed in Section II. C and in Tables II and III, will probably be 

 found to influence the course of its oxidation by periodate. In this connection 

 it is noteworthy that the product of the oxidation of weso-inositol by 

 Acetohadcr suboxijdans,''' ^' which carries a carbonj^l group in position 

 2 instead of the polar hydroxyl ,"* is cleaved in a normal manner by periodic 

 acid,^- and that, on the other hand, the tetraacetyl derivative of meso- 

 inositol containing a cts-glycol structure, which comprises a polar and an 

 adjacent equatorial hydroxyl, is not attacked by periodate.^ 



A number of mono- and dicarbonyl derivatives of the different cyclo- 

 hexitols may be obtained through the action of Acetobader suboxydans. 

 (Compare also Section II. C.) The inosose produced from meso-inositol^^ 

 has the following structure.'^ 



ep2-Inositol (II) yields a levoratory keto derivative wdth the following 

 structure.'* • ^- ^^ 



p 



^'T. Posternak, Helv. Chim. Ada 19, 1333 (1936). 



"* P. Fleury, G. Poirot, and J. Fievet, Compl. rend. 220, 664 (1945). 



"' A. J. Kluyver and A. G. J. Boezaardt, Rec. trav. chim. 58, 956 (1939). 



«2 D. ]J. Sprinson and E. Chargaff, ./. Biol. Chern. 164, 433 (1946). 



