Riboflavin (vitamin B2)

Riboflavin was isolated in  a crystalline form from milk by Kuhn  and co-workers in 1933.  Because of this,  the  early  name  of  the  vitamin  was  lactoflavin.  It  was synthesized  by two independent groups of scientists working with Kuhn  in  1935.

 Riboflavin has an  isoalloxazine nucleus i.e. a pteridine ring with a benzene ring fused on  to  it.  The side  chain  is  a  C5-polyhydroxy  group,  a  derivative of  ribitol, a  pentahydroxy  compound. Riboflavin is chemically known  as  6,7-dimethyl-9-D- ri  bitylisoalloxazine. The structure of riboflavin  is given in Figure 3.3. Once again, do not get intimidated by the chemical names of this compound. As a student of dietetics you  liiay  not  be asked  as  such  to  illustrate the  structure of these compounds, but surely knowledge of  the  structure will help you  understand  the  compound and  its properties better.