So we see that inside our body it's the ring structure, the sugars that predominate. In the case of six member rings, we have the chair confirmation. And in the case of the five member rings we have this envelope form, this puckered form that will basically exist. And we either have the C two endo or the C three endo. In the C two endo it's a second carbon. It's a second carbon that ends up being puckered.