Folic Acid: Solution Structure and NMR Strategy for Conformational Analysis

The solution structure of folic acid was determined by the combined use of NMR experimental results, mechanics and dynamics calculations, and theoretical simulation of NMR spectra. The solution structure of folic acid showed a different molecular rearrangement to the X-Ray conformation. In particular, we identified a hydrogen bond which stabilizes a folded glutamic acid molecular moiety between the NH₍₁₈₎ and the C₍₂₃₎ carboxylic group. A different spatial conformation of the phenyl ring was also found.