What functional group is folic acid part of, and use the chemical structure to explain why?

Answer 1

Folic acid and folate (the anion form) are forms of the water-soluble Vitamin B9. These occur naturally in food and can also be taken as supplements. Folate gets its name from the Latin word folium ("leaf").
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In the form of a series of tetrahydrofolate compounds, folate derivatives are substrates in a number of single-carbon-transfer reactions, and also are involved in the synthesis of dTMP (2'-deoxythymidine-5'-phosphate) from dUMP (2'-deoxyuridine-5'-phosphate). It helps convert vitamin B12 to one of its coenzyme forms and helps synthesize the DNA required for all rapidly growing cells.

The pathway leading to the formation of tetrahydrofolate (FH4) begins when folate (F) is reduced to dihydrofolate (FH2), which is then reduced to tetrahydrofolate (FH4). Dihydrofolate reductase catalyses both steps.