Acids, Formyltetrahydrofolic

Tetrahydrofolates which are substituted by a formyl group at either the Nitrogen atom in the 5 position or the Nitrogen atom in the 10 position. N(5)-Formyltetrahydrofolate is Leukovorin (citrovorum factor) while N(10)-formyltetrahydrofolate is an active coenzyme which functions as a carrier of the formyl group in a number of enzymatic reactions.