A Computational Study of a Prebiotic Synthesis of Folic Acid (Vitamin B9)

The planetary molecules cyanogen, cyanoacetylene, hydrogen cyanide, ammonia, and carbon monoxide and hydrogen are invoked in a synthesis of the pteridine precursor of the vitamin folic acid. This is followed by the formation of a p-methylamino benzoyl α-glutamic acid from the planetary gases diacetylene, acetylene, hydrogen cyanide, carbon monoxide, ammonia, water and hydrogen. This latter requires a surface catalyzed, photochemically activated synthesis on the magnesium metalloporphyrin catalyst. The addition of several 5-amide glutamic acid entities may be added on the same catalyst surface. Finally the pteridine derivative and the p-methylamino benzoyl-α-glutamic acid derivative are combined to give the folic acid vitamin. The reactions have been shown to be feasible from the overall enthalpy changes in the ZKE approximation at the HF and MP2 /6-31G* level, and with acceptable activation energies.