THE HT.VVK OF Tin: Hl(!.\h' l\ Till: HLDOh 645 



rai)icll\- uiuler<iULS eiiemical cluinge. But botli types of phase are 

 present in both blood and cells although in different proportions. 

 The blood is therefore the phase par excellence in which to study the 

 " Sucre actuelle" and the tissues the place to study the "sucre vir- 

 tuelle." According to this conception "sucre virtuelle" would be 

 glucose in process of utilization or storage and not beyond recall, 

 hence chiefly glucose polymers. 



DIOSE 13 



Diose, glyt'ollic aldeliyde, CH.OH-COH, the simplest sugar, of whicli there is 

 but one possible form, is higlily sensitive to oxidative infhiences and, in vitro, 

 readily roiidenses with alkali to yield a complex mixture of higher sugars and 

 saccharinic acids in a manner analogous to that manifested liy tlie trioses. Not- 

 withstanding its instability and sensitiveness to oxidative clianges in the test 

 tube, it would appear that glycollic aldehyde is insusceptible of direct oxidation 

 in the body but that it may be converted into glucose, like other sugars, and then 

 utilized. When given intravenously at the rate of only 0.1 gm. per kg. per hour, 

 unchanged diose appears in the urine after the first few minutes of injection 

 (author). P. Mayer reported glycosuria and death following administration of 

 imi)ure glycollic aldehyde to rabbits. Parnas and Baer saw an increase of glycogen 

 in tortoise livers perfused with glycollic aldehyde. This is confirmed by Barren- 

 scheen. Smedley noted the rapid disappearance of diose added to liver emulsions. 

 Sansum and Woodyatt, and also Greenwald observed slight increases of the 

 glycosuria following parenteral administrations of diose in phlorhizinized but not 

 completely deglycogenized dogs. The extra sugar could liave come from glycogen 

 in these experiments. A Hnal proof of the conversion of diose into glucose in the 

 living bodv has not been brought. The relationship of this substance to glvcine, 

 CH.XH,-COOH; glycollic acid, CH,OH-COOH; and ethyl alcohol, CH.rCH.OH; is 

 close. Lusk states that glycine is capable of conversion into glucose in the body. 

 However, glycollic acid and alcohol are apparently not sugar formers. 



TRIOSES 11 



There are three possible trioses, d- and 1-glyceric aldehyde and the ketotriose 

 dihydroxyacetone. Tlie optically inactive d, 1-glyceric aldehyde has been jircpared 

 ami recently the d- and 1-forms. The preparation is still tedious and expensive. 

 Dihydroxy-acetone is somewhat easier to prepare. Both trioses are imstable, 

 easily oxidized and very prone to undergo rearrangements and condensation with 

 even traces of alkali. lender the inlluence of alkali they yield complex mixtures of 

 hexoses, chiefly S-kctohexoses, formerly known as a and /3-acrose from which 

 Schmitzis has recently isolated d,l-fructose and d,l-sorbose. If oxygen is avail- 

 able as well as alkali, they burn. If the alkali is strong and oxygen lacking, much 

 lactic acid is formed together with certsiin rearranged tetrose, pentose and hexose 

 molecules, known as saccharinic acids (or "saccharines," of Kiliani). The same 

 phenomena occur when the alkali is dilute, but more slowly. The structural 

 formuht of the trioses and their relationship to glycerol, glyceric acid and lactic 

 acids (the latter of which might be regarded as a .3-carbon saccharinic acid) may 

 be seen from the following chart: 



13 Literature on diose: Mayer, P., Zeit. f. physiol. Chem., 100,3 (.38). 135; 

 Woodvatt, R. T., .Tour. Amer.' Med. Assoc, 1010 '(5.5). 2100; Parnas and Baer, 

 Biochem. Zeit., 1012 (41), 386; Smedlev, Ida, .Tour. Phvsiol., 1012 (44), 203; 

 Sansum, W. D. and Woodyatt, R. T., .Toiir. Biol. Chem., 1014 (17) r)21. 



1* Literature on Trioses: The cliemical literature is reviewed and an improved 

 method of preparing glyceric aldehyde described by Witzemann, K. .!., .Ttnir. Am. 

 Chem. Soc, 1014 (36)", lOOS, and ihid., p. 222.3. The biological literature is 

 reviewed bv Sansum, W. D. and Woodvatt. 15. T.. .Tour. Biol. Chem., lOKi (24). 327. 



isBer. Deut. Chem. Ges., 1914 (46)', 2327. 



