Vitamin B6. Computer graphic depicting a molecule of vitamin B6 (pyridoxine hydrochloride). The molecular formula is C8.H11.NO3. Atoms appear as spheres, joined by atomic bonds. Atoms are colour- coded: carbon (green), nitrogen (blue), oxygen (red), hydrogen (yellow). Vitamin B6 is one of the water-soluble B complex vitamins which, although they are chemically unrelated, perform similar functions in the body and are found in common dietary sources. Vitamin B6 is used by the body to form pyridoxal phosphate, a co-enzyme involved in the transamination of amino acids. Deficiency of vitamin B6 is rare. It is found in vegetables, milk, eggs and meat.