A compound formed by the reaction of a pyranose sugar with a nonsugar molecule (an aliphatic or aromatic hydrocarbon) termed the aglycone. The aglycone replaces the hydrogen in the hydroxyl group of carbon atom one of the sugar ring. Glucose is the sugar component of many glycosides, such compounds being called glucosides. Some rare sugars are only found in glycosides, e.g. digilalose, which has only been detected in certain Digitalis glycosides. Major classes of glycosides include the anthoxanthin glycosides, important as plant pigments, the steroid glycosides (see saponin
, cardiac glycoside
), and the cyanogenic glycosides, which release hydrogen cyanide on hydrolysis. An example of the last group is the glucoside amygdalin, which is obtained from certain members of the Rosaceae, e.g. almond (Primus amygdalus) and peach (Prunus persica). Cyanogenic glycosides may act to deter grazing animals.