Reactions of glucose that cannot be explained by open chain structure :
(i) Glucose gives the characteristic reaction of alcohols and carbonyl group (aldehydes and ketones). However it does not form addition compound with ammonia and sodium bisulphite and does not respond to 2, 4-DNP test and Schiffs test.
(ii) The penta-acetate of glucose does not react with hydroxyl amine indicating the absence of free - CHO group.
