Which Form of D-Glucose Does NOT Exist as a Result

Question

Which form of D-glucose does NOT exist as a result of mutarotation?
A)L-glucopyranose
B)b-anomer
C)free aldehyde
D)a-anomer

Accepted Answer

Mutarotation is the process in which anomer of a sugar shifts to the other due to the equilibrium between the open-chain and cyclic form. Hence, all forms of D-glucose can be converted to its other anomer or the open-chain form through mutarotation. However, L-glucose is the enantiomer of D-glucose, and its cyclic form would be L-glucopyranose, which is different from the forms of D-glucose obtained through mutarotation. Therefore, L-glucopyranose (A) does not exist as a result of mutarotation.