Structural elucidation, solvent (polar and non-polar) effect on electronic characterization, non-covalent charge interaction nature, topology and pharmacological studies on NLO active l-argininium methanesufonate

Abstract

Reaction of l-arginine (l-Arg) with methanesulfonic acid (l-ArgH) (CH3SO3) in aqueous solution was investigated. The method of synthesis of (l-ArgH)(CH3SO3) was solvothermal. The precursors l-arginine and methanesulfonic acid was dissolved in aqueous solution. The solution was allowed to slowly evaporate, leading to the formation of non-centrosymmetric crystals of (l-ArgH)(CH3SO3). The crystal structure was determined using X-ray diffraction analysis. Using Hirshfeld surfaces and 2D-fingerprint plots, the interactions between the crystal structures were studied. The structure is optimized using density functional theory (DFT) at the B3LYP/ 6–31 + G* level in gas phase which in turn compared with the empirically determined molecular structure in the solid state. Vibrational spectrum analyses were also used to characterise the (l-ArgH)(CH3SO3) salt. To ascertain the energy gap, the HOMO-LUMO behaviour in several solvents (polar and non-polar) has been performed. The HOMO-LUMO energies from various liquids (polar and non-polar) indicate that the molecules are interacting via charge transfer. The interaction of the lone pair, bonding, and anti-bonding molecular orbitals has been evaluated by NBO. Topology investigations also shed light on the molecule's molecular structure and reactivity. The molecular electrostatic potential illustrates the potential for electrophilic and nucleophilic sites in a molecule for different solvents. A few polar and non-polar solvents were computed for NLO characteristics such the dipole moment, total polarizability, and first order hyper polarizability in addition to the gas phase. The SHG efficiency of (l-ArgH)(CH3SO3) salt relative to KDP was found to be 0.9. SwissADME is performed to get the drug likeness of the grown (l-ArgH)(CH3SO3).