Remarks concerning Certain Nonitol Configurations

One observes that it lies in the more accessible course in both the d-mannose and o-galactose series indeed, its parent octoses are known (n-manno-L-manno-octose and D-gala-L-giafa-octose) and its preparation from the two series seems feasible. 

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- olo-heptose is the epimer of minor yield by the cyanohydrin addition, the 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. 

The configuration also lies in the D-mannose series (o-manno-L-gfuZo-nonitol) it is in the more accessible path in two of the three steps, and only the passage from the D-manno-n-giaZa-heptose to n-manno-L-gfZuco-octose might be expected to give a low yield. 

2-ketose but it could be either mannoheptulose or sedoheptulose (see p. 13) and his data do not lead to a distinction between them. 

A Simple Proof of the Configurations in the Glucose and Galactose Series 

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