Alkali-Sensitive Glycosides

C. E. Ballou, Alkali-sensitive glycosides, Adv. Carbohydr. Chem., 9 (1954) 59-95. 

The descriptive term alkali-sensitive glycoside has special significance to one concerned with a study of the chemistry of carbohydrate substances, for experience often refutes the generalization that the gly-cosidic linkage is stable to alkalis. The acid-catalyzed hydrolysis of glycosides is well known, and is characteristic of the acetal structure they possess.1 However, it is not practical to assume that most glycosides have... 

Alkali-sensitive glycosides may be classified into three types (1) glycosides of phenols, (2) glycosides of enols, and (3) glycosides of alcohols substituted in the /8-position by a negative group. 

A third type of alkali-sensitive glycoside was described by Kuhn and Lowin 1941.13 Picrocrocin [(—)-4-hydroxy-2,6,6-trimethyl-l-cyclohexene-l-carboxaldehyde-(4 — 1) /3-D-glucopyranoside] (VIII), the bitter principle of saffron, was observed to decompose in aqueous alkali with the formation of D-glucose and the unsaturated aglucon safranal (2,6,6-tri-... 

Besides picrocrocin, at least one other naturally occurring glycoside would be expected to demonstrate the alkali-sensitivity of this class. Jarvis and Johnson63 have described a glycoside (LXXXIV), produced by... 

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