Properties of the Higher-carbon Sugars

An outstanding property of most heptuloses is the ease with which they form anhydrides (2,7-anhydroheptulopyranoses) under acidic conditions. The methods used for identifying these products are similar to those 

Aldoheptoses are less ready to form anhydrides in acidic solution, although 1,6-anhydroheptopyranoses are obtained in yields of 43% and 7%, respectively, from D- Ij/cero-n-fdo- and D-g ij/cero-D-g(MZo- %eptoses. At the same time, the latter furnishes the unique 1,7-anhydro-n-gZycero-/S-D-yuZo-heptopyranose (77) in 12% yield. 

It is noteworthy that heptoses having the aliro, gido, or ido configura- 

Institute of Organic Chemistry, University of Basel, Switzerland 

A chapter by Elderfield discussing the carbohydrate components of the cardiac glycosides and one by Overend and Stacey concerning 2-deoxy sugars in general have appeared in this Series. Other reviews have also been published. A certain amount of repetition of some aspects of the subject will therefore be unavoidable in this presentation. This compilation was written in August 1960, but, so far as possible, references to literature up to July 1961 have been added. 

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