All of the following are vitamers of Vitamin B6, except:

Vitamers: The term vitamers represents the chemically similar substances that possess qualitatively similar vitamin activity.  Some good examples of vitamers are given below: Retinol, retinal and retinoic acid are vitamers of vitamin A. Pyridoxine, pyridoxal and pyridoxamine are vitamers of vitamin B6. Key Concept: Pyridoxine, pyridoxal and pyridoxamine are vitamers of vitamin B6. Ref : 1- Textbook of Biochemistry, Satyanarayana