2.2.5(p. 295) Most of the monosaccharides found in living organisms are the D-isomers(e.g, D-ribose, D-glucose, D-galactose, D-mannose fructose 2. 2.6 Each stereoisomer has a different conventional name, ending with“-0se” suffix 2. 2. 7 Ketoses are often named by inserting an"ul into the name of the corresponding aldoses(e.g aldopentose is named as ribose, the ketopentose is named as ribulose
2.2.5 (p. 295) Most of the monosaccharides found in living organisms are the D-isomers (e.g., D-ribose, D-glucose, D-galactose, D-mannose, Dfructose) 2.2.6 Each stereoisomer has a different conventional name, ending with “-ose” suffix. 2.2.7 Ketoses are often named by inserting an “ul” into the name of the corresponding aldoses (e.g., aldopentose is named as ribose, the ketopentose is named as ribulose
2.2.8 Two sugars differing in configuration at a single asymmetric carbon is called epimers to each other(e.g D-glucose and D-mannose are epimers at C-2; D-glucose and D-galactose are epimers at C-4) 2.2.9 Monosaccharides easily form intramolecular hemiacetals(in aldoses or hemiketals (in ketoses) in aqueous solutions. (fig. 2.2.10The optical activity of D-glucose slowly changes when dissolved in water
2.2.8 Two sugars differing in configuration at a single asymmetric carbon is called epimers to each other (e.g., D-glucose and D-mannose are epimers at C-2; D-glucose and D-galactose are epimers at C-4). 2.2.9 Monosaccharides easily form intramolecular hemiacetals (in aldoses) or hemiketals (in ketoses) in aqueous solutions. (fig.) 2.2.10 The optical activity of D-glucose slowly changes when dissolved in water
Three carbons Four carbons Five carbons H OH HO-C-H -OH HO H-C-OH HO H-C-OH HO H-C-OH H-C-OH H-C-OH H-C-OH OH CHOH CH2OH H,OH CH OH CHOH CH,OH THreose D-Ribose D-Arabinose DXylose D-Lyxose Six carbons H H OH HO--C-H OH HO H HO--C-H H→C-OHHo -OH H-C-OH HO--C-H HO→C-H H-C-OH HO-C-H H-C-OH H-C-OH H→C- OH HO-C-H HO--C-H HO→C-H H-C-OH H-C-OH H-YOH H-C-OH H-C-OH H-C-OH H-C-OH H-C-OH CHOF CH,OH H,OH CHOH CH, OH CH OH CH,OH CH,OH D-Allose D-Altrose D-Glucose D-Mannose D-Gulose D-Idose D-Galactose D-Talose DAldoses (a)
Three carbons HO H-C-OH CHoO D-Glyceraldehyde
Four carbons H O H O C C HC-OHHO-C—H H-C-OH H-C-OH CH2OH CH2Oh D-Erythrose D-Threose