Question
What is essentially the difference between $\alpha$-glucose and $\beta$-glucose? What is meant by pyranose structure of glucose?
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Answer
$\alpha$-glucose $\& \beta$ glucose differ only in the orientation of the hydroxyl group at $\mathrm{C}_1$ position. In $\alpha$-glucose the OH group is on right-hand side at $\mathrm{C}_1$ position whereas in $\beta$-glucose the OH group is on left-hand side at $\mathrm{C}_1$ position. The six-membered hetero cyclic structure of glucose is called pyranose structure.
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