What is the difference between alpha and beta glucose?

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Answer 1 · 2015-12-04T03:04:46

They differ in the orientation of the $"OH"$ group at $"C-1"$ .

When the straight-chain form of glucose closes to form a ring, it forms a new chiral centre at $"C-1"$ .

This gives two different structures.

Their Haworth formulas are

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Structure 1

and

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Structure 2

To assign the α or β configurations to these forms, you look at the relative positions of $"C-6"$ and the $"OH"$ group on $"C-1"$ .

In the α- form (Structure 1), the $"OH"$ group on $"C-1"$ is on the opposite side of the ring from $"C-6"$ .

In the β- form (Structure 2), the $"OH"$ group on $"C-1"$ is on the same side of the ring as $"C-6"$ .