Monosaccharides
COMMON HEXOSE SUGARS
• Hexose: 6-carbon sugars
• Building blocks for complex carbohydrates/macromolecules
• Substrates for several metabolic rxn's
• Cellular energy store
• Same formula: C6H12O6 --> isomers
D-glucose
• Aldose sugar: aldohexose
• Pyranose ring: hexagonal ring structure
D-mannose
• Aldohexose
• C2 -OH group faces opposite direction of D-glucose
D-galactose
• Aldohexose
D-fructose
• Ketohexose (6-carbon ketose sugar)
• Furanose ring: pentagon shaped ring
RING FORMS OF SUGARS
• Monosaccharides self react: hemiacetal (aldoses) or hemiketal (ketoses) rxn
• Hemiacetal: aldehyde + alcohol
• Hemiketal: ketone + alcohol
• Rearrangement reactions: atoms change position; atoms not added/lost