# Homework Help: Planar representation to chair conformation

1. Nov 22, 2008

### leopard

For carbohydrates, the $$\alpha$$ position is to the right in a Fischer projection and down in a planar representation. Is it axial or equatorial in a chair conformation?

My book also says that all the OH groups in $$\beta$$-D-glucose are in axial positions. Is this true?

2. Nov 24, 2008

### chemisttree

You will note that in $$\beta$$-D-glucose the OH groups alternate left and right. This is the perfect alignment to have all of the OH groups in an equatorial arrangement. It is also the perfect alignment to have all of the OH groups (and the CH2OH group) in an axial arrangement. Which arrangement would be of lowest energy?