Heptonic acids

CN D-g/ycero-D-gw/o-heptonic acid compd. with erythromycin (1 1)... 

I, 7-diphosphate.170 1 (f> This tetrose phosphate is involved with phosphoenol pyruvate in the formation of shikimic acid via 3-deoxy-2-keto-D-ara6ino-heptonic acid 7-phosphate and, hence, of aromatic compounds.170(d) A synthesis of the tetrose phosphate has been described.170 1 Aldolase shows a high affinity for the heptulose diphosphate and, compared with that for D-fructose 1,6-diphosphate, the rate of reaction is about 60 %. The enzyme transaldolase, purified 400-fold from yeast, catalyzes the following reversible reaction by transfer of the dihydroxyacetonyl group.l70(o>... 

In the form of sodium salts all are very soluble and have low freezing points, so that solidification in winter conditions is unlikely. Figure 1.8 shows the types and formulae of materials which have been reported to find application in the formulation of this type of water-reducing admixture. However, the only materials finding widescale application in formulations are the salts of gluconic and heptonic acids. 

Synthesis of 7-Amino-2,6-anhydro-7-deoxy-L-g/ycero-L-g /o-heptonic Acid... 

Of all these products, sodium glucoheptonate has been the most widely used chelant in cooling water formulations. It shows a greater stability than sodium gluconate and retains the ability to chelate ions effectively in high pH water, which citrates and EDTA do not do so well. Sodium glucoheptonate is a sodium salt of polyhydroxymonocarboxylic acid (2,3,4,5,6,7-hexahydroxy-s-heptonic acid). It is a reaction product of sodium cyanide and sucrose. 

G. P. Smirnova, N. V. Chekareva, O. S. Chizhov, B. M. Zolotarev, and N. K. Kochetkov, Mass spectrometry of sialic acids Peracetylated methyl esters of 5-acylamino-3,5-dideoxy-nononic and -heptonic acids, Carbohydr. Res., 59 (1977) 235-239. 

Gluconic acid Salicylic acid Heptonic acid Malic acid ... 

D-Gala-irffoZo-octose oxime, IV, 124 heptaacetate, IV, 124 octaacetate, IV, 150 D-Gala-L-ffluco-heptitol, I, 9, 11 and heptaacetate, I, 35 L-Gala-D-gluco-heptitol, I, 14 and heptaacetate, I, 35 L-Gala-D-gfuco-heptonic acid, 7-desoxy-, I, 30... 

L-Gala-D-monreo-heptitoI, 7-desoxy-, V, 9 D-Gala-L-manno-heptonic acid, I, 3 L-Gala-D-manno-heptonic acid, 7-desoxy-, I, 30 V, 9... 

Heuser, Emil, obituary of, 1 Heptonic acid, 3-deoxy-D-( JMCo(or man-no)-, 7-phosphate, 250 —, 3-deoxy-n-jiwco(or rmnno)-, methyl ester, 250... 

The use of this procedure has led to the crystallization of one of the two possible epimeric lactose carboxylic acids (c/. ref. 12, p. 5), which proved to be D-gluco-o- ulo-heptonic acid with the /3-D-galacto-pyranosido attachment at its carbon atom 5. Attempts so far to lac-tonize this acid have failed. 

II3C - C C C C C COOH irGala-D-7nanno-7-deBoxy-heptonic acid and H OH OHH H... 

It has been mentioned (p. 13) that D-manno-o-tolo-heptitol is identical with natural voleraitol. If -one desires a supply of voleraitol, probably the best procedure at the present time is its synthetic production from D-mannose even though the D-manno-D-synthetic method appears to be more practicable than the isolation of the alcohol in quantity from known natural sources. The use of barium cyanide or the equivalent mixture of a barium salt and sodium cyanide, in place of hydrocyanic acid appears to favor the yield of the desired heptonic acid. On the other hand, the possibility of starting with o-altrose, which is now no longer a particularly rare sugar, appears of interest because the desired heptose (D-altro-D-mormo-heptose) should be the major product in that series if the generalizations that have been presented hold for altrose. This speculation has been offered because it seems to the writer that many carbohydrates that are now only laboratory curiosities, can be made at costs that are not prohibitive for the use of them in exploratory researches, especially in the bacteriological, physiological and biochemical fields. 

Cyanohydrin formation from lactose was first described by Fischer in 1890 and later by Hann and Hudson,who used aqueous sodium cyanide in the presence of calcium chloride at 0°. After alkaline hydrolysis, 4-0- -D-galactopyranosyl-D- /j/cero-D- wfo-heptonic acid was crystallized in 26% yield. 

---