# What do two sugar isomers have in common?

Oct 18, 2016

Isomers are compounds which share a molecular formula but have different structures. E.g., glucose and fructose are both ${C}_{6} {H}_{12} {O}_{6}$, but have different structures.
As you can see here, glucose contains a 5 carbon ring and only one hydroxymethyl group ($C {H}_{2} O H$), whereas fructose contains a 4 carbon ring and two hydroxymethyl groups. They do, however, contain the same number of each type of atom and are able to be converted to each other by isomerase enzymes.