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44 2. Write formulas of ribose, deoxyribose, fructose in an open form (Fisher’s formula) and in cyclic furanose form (Heuorths’s formula). 3. Write the formulas of glucose, galactose, mannose in the open form (Fish- er’s formula) and in the cyclic pyranose form (Heuorths’s formula). 4. Write formulas for α-anomers and β-anomers of glucose, galactose, fructose. 5. Write formulas for the products of oxidation and reduction of glucose and galactose. 6. Write formulas for monosaccharide derivatives: • phospho derivatives: ribose‑5‑phosphate, glucose‑1‑phosphate, glucose‑6‑ phosphate, fructose‑1‑phosphate, fructose‑6‑phosphate, fructose‑1,6‑diphosphate. • amino derivatives: glucosamine, galactosamine. • N‑acetylamine derivatives: N‑acetylglucosamine, N‑acetylgalactosamine. Laboratory work Experiment 1. Proof of the presence of hydroxyl groups in D‑glucose. Put 1 drop of 0.5% D‑glucose solution and 6 drops of 10% NaOH into the tube. Add 1 drop of 2% solution of CuSO 4  to the resulting mixture. The precipitate of Cu (OH) 2  is formed, which quickly dissolves and a clear blue solution is obtained. Keep the resulting solution for the next experiment. Copper (II) hydroxide forms a blue solution with compounds having diol fragments. The chelate compound is formed in this reaction: H H Cu O H C (CHOH) 2 O-CH O-CH CH 2 OH HOCH 2 CH-O CH-O (CHOH) 2 C H O + Cu(OH) 2 HOCH 2 CH-OH CH-OH (CHOH) 2 C H O + 2H 2 O Experiment 2. Reduction of copper (II) hydroxide by glucose in an alkaline medium (Trommer test). Pour distillated water to the height of the liquid layer in a test tube of 18–20 mm into the blue solution obtained in the previous experiment. Heat it over the flame of the spirit lamp. The tube should be kept so that only the upper part of the solution is heated, and the lower one remains for monitoring (without heating). Heat only until the boiling point, but do not boil. When heated, the color of the top of the solution changes from blue