二、单糖( Monosaccharides) )结构( Structures) 差向异构体( Epimers)— Distereomers that differ in configuration at only one chirality center are called epimers HC=O HC=O HC=O HC=O HO-H HO H-oh HoH H-OH HO OH H-OH HO→H HO HHH H-OH H-OH H-OH H-OH CH,OH CH,OH CH,OH CHoO D-ribose D-arabinose D-idose D-talose C-2 epimers C-3 epimers二、单糖（Monosaccharides） （一）结构（Structures） 差向异构体 ( Epimers ) ——Distereomers that differ in configuration at only one chirality center are called epimers