1. 13.4 Chemical Properties of Monosaccharides 1  Tautomerization (enol-keto tautomerization) Main Menu  Reduction  Oxidation [H] [O]

2. Example of Tautomerization 2 Dihydroxyacetone phosphate 5 th Reaction in glycolysis Mechanism: Glyceradehyde 3-phosphate Triosephosphate isomerase

3. Example of Reduction 3 Hydrogenation of xylose Xylitol, a common ingredient in chewing gum and other food products, was first discovered almost simultaneously by German and French chemists in the late 19th century. Xylitol is produced by hydrogenation (reduction) of xylose, which converts the aldopentose into a primary alcohol. xylose H 2, metal catalyst xylitol

4. Example of Oxidation 4 Oxidation of glucose Gluconic acid occurs naturally in fruit, honey, and wine. As a food additive (E574[2]), it is an. It is used as acidity regulator or cleaning products. Calcium gluconate is used to treat burns from hydrofluoric acid. Quinine gluconate is a salt between gluconic acid and quinine, which is used for intramuscular injection in the treatment of malaria. Zinc gluconate injections are used to neuter male dogs. Iron gluconate injections have been proposed in the past to treat anemia [O] glucosegluconic acid

5. 5 Learning Check 1. Tollens' reagent (Ag(NH 3 ) 2 + ) can be used to differentiate aldoses and ketoses (Tollens’ test). Which of the following description is correct based on the following reaction scheme of Tollenes’ test? (a) This is an oxidation where sugar is reduced. (b) This is a reduction where sugar is reduced. (c) The starting sugar is a lactone. (d) The produced sugar is a lactone. (e) None of the above positivenegative

6. 6 Learning Check 2. Which of the following is the tautomer (isomer from tautomerization) of glucose? (a) I (b) II (c) III (d) IV (e) None of the above Main Menu