The Vitamin C molecule in 3-D

The Vitamin C molecule - rotatable in 3 dimensions

Vitamin C - ascorbic acid - is well known for its ability to prevent scurvy, which is characterised by a number of problems with connective tissue and bone.Vitamin C is an electron donor and acts as a cofactor for several different hydroxylase enzymes in the human body, notably those involved in hydroxylation of proline and lysine in the synthesis of collagen.
As an antioxidant, it is sometimes added to foods - especially snack foods containing fats, e.g. crisps, to prevent them from becoming rancid.
Current chemical names:
2-Oxo-L-threo-hexono-1,4-lactone-2,3-enediol
or
(R)- 3,4-dihydroxy -5-((S)- 1,2-dihydroxy ethyl) furan-2 (5H)- one
Label ring numbers
Label/ Unlabel atoms

Ascorbic acid used to be called L-hexuronic acid, which reminds us that there is another isomer: D-hexuronic acid, which has no such ability (to prevent scurvy).