tereoisomers Diastereomers enantiomers
Stereoisomers = Diastereomers + enantiomers
Ketose-aldose pairs of sugars frequently are named by inserting the letters ul in the name of the corresponding aldose to derive the name of the ketose, an example is erythrose-erythrulose
Ketose-aldose pairs of sugars frequently are named by inserting the letters 'ul' in the name of the corresponding aldose to derive the name of the ketose. An example is erythrose - erythrulose
The predominant forms of glucose and fructose in solution are not open chains. Rather, the open-chain forms of these sugars cyclize into rings. In general, an aldehyde can react with an alcohol to form a hemiacetal 0 H R—C+HOR′=R-C-0R H OH Aldehyde Alcohol Hemiace
HO OR C、+HOR′ C R H R H Aldehyde Alcohol Hemiacetal
The C-1 aldehyde in the open-chain form of glucose reacts with the C-5 hydroxyl group to form an intramolecular hemiacetal. The resulting six- membered ring is called pyranose because of its similarity to byran. 6 CH2OH H OH H Reducing group OH H OH CHOH D-Glucopyranose 2 H-C-OH H C-OH H 3 H0-C-H=c OH H 4 H-C-OH 5 H-C-OH H OH CHOH CH,OH D-Glucose (Open-chain form) OH OH H HO OH B-D-Glucopyranose