Structural studies, solubility, and aqueous solvation of Vitamin B6 using Car-Parrinello Molecular Dynamics

This study aims to elucidate the influence of an aqueous environment on the geometric and electronic properties of pyridoxine through CPMD simulations. The supramolecular arrangement in the crystalline state was investigated using HS analysis, complemented by cohesive energy calculations comparing the solid and solution phases to understand the dissolution process. Helmholtz free energy calculations confirm that these interactions are thermodynamically favorable, with geometric analysis classifying them as moderately strong hydrogen bonds. Topological analysis of the electronic density revealed that two of these interactions range from weak to moderate in strength after stabilization, while the remaining two vary from weak to strong. HS analysis highlighted the presence of significant intermolecular hydrogen bonds, which are responsible for the formation of a zigzag-shaped, sheet-like crystalline network structure. Cohesive energy assessments support the experimental observation of pyridoxine's solubility in water. These findings provide valuable insights into the molecular behavior of vitamin B6 in solution, thereby enhancing our understanding of its chemical properties and biological activities.