Cyanocobalamin (CNCbl)

Cyanocobalamin is the most common and widely produced of the chemical compounds that have vitamin activity as vitamin B12. Vitamin B12 is the "generic descriptor" name for any of such vitamers of vitamin B12. Because the body can[citation needed] convert cyanocobalamin to any one of the active vitamin B12 compounds, by definition this makes cyanocobalamin itself a form (or vitamer) of B12, albeit a largely artificial one. Cyanocobalamin usually does not occur in living organisms, but animals can convert commercially produced cyanocobalamin into active (cofactor) forms of the vitamin, such as methylcobalamin. The amount of cyanide liberated in this process is so small that its toxicity is negligible. Cyanocobalamin is the most famous and widely produced vitamer in the vitamin B12 family (the family of chemicals that function as B12 when put into the body), because cyanocobalamin is the most air-stable of the B12 forms.