Question

How can I draw axial and equatorial bonds in glucose?

Answer 1

You follow the steps below.

Explanation:

Step 1. Draw the Fischer projection of glucose.

Step 2. Draw a cyclohexane chair, showing the axial and equatorial bonds.

Replace `"C-6"` of the ring with an `"O"` atom (the `"O"` atom on `"C-5"` of glucose), and place the bulky `"CH"_2"OH"` group in the equatorial position of `"C-5"`.

Step 3. Insert the `"OH"` groups on `"C-2"` to `"C-4"`.

In the Fischer projection their orientations are in the order "right-left-right".

In the pyranose chair, the orientations will be "down-up-down".

Draw the `"OH"` groups on `"C-2"` and `"C-4"` in the "down" (equatorial) positions.

Draw the `"OH"` group on `"C-3"` in the "up" (equatorial) location.

Draw an `"OH"` below the ring (axial) on `"C-1"` for the α form. Draw it above the ring (equatorial) for the β form.

The chair form of α-D-glucopyranose is

And the structure of β-D-glucopyranose is

As you move around the β-glucose ring, you see that all the substituents are equatorial.