D-Fructose can also form a six-membered ring. Draw the β anomer of D-fructose in the six-membered ring form.

Trehalose is a naturally occurring disaccharide used in cosmetics because of its ability to retain moisture. The formal name of trehalose is glucose α, α(1→1) glucose. Draw the structure of trehalose. Is it a reducing or nonreducing sugar?