Definition of Furanose
Furanose is a class of carbohydrates that has a five-membered ring system. The chemical structure of these carbohydrates shows that there are four carbon atoms and one oxygen atom. There are no double bonds present in their structure as in furan which is an oxygen heterocycle. The furanose ring is either a cyclic hemiacetal of an aldopentose or a cyclic hemiketal of a ketohexose.
The anomeric carbon of the carbohydrate is present on the right of the oxygen atom. There are two configurations of this i.e. D-configuration and L-configuration. In L-configuration, the most substituted chiral carbon is pointed downwards whereas, in D-configuration, the most substituted chiral carbon is facing upwards. They are also present in α and β configuration.