Structural and vibrational characterizations, DFT calculations, second harmonic generation, molecular docking studies on L–argininium 3,3-dimethylacrylate

Abstract

This study is aimed to understand the structure, stability, and properties of L-argininium 3,3-dimethylacrylate (ADMA) crystals. These single crystals were cultivated through a solution growth method. The structure describes the orthorhombic crystal system with four molecules per unit cell, and crystallizes in a non-centrosymmetric (P212121) space group. A systematic structural analysis of ADMA was carried out using density functional theory (DFT) with a B3LYP/6-31+G* basis set to examine the intra/intermolecular type of bonding interactions, excitation energies, vibrations, and electrostatic interaction between the charged particles. The protonated L-argininium cation and dissociated 3,3-dimethylacrylate anion are joined via N–H⋯O hydrogen bonds with R22(8) to form an asymmetric unit of ADMA. The energy of interaction between l-arginine and 3,3-dimethylacrylic acid molecules was calculated to be 17.95 kcal mol−1 (75.09 kJ mol−1), leading to the formation of a 1:1 salt molecule. Additionally, the Density Functional Theory (DFT) calculations supported the assignment of vibrational bands. The calculated frontier molecular orbital energy gap 4.702 eV indicating the charge transport that happens between the cation and the anion. Furthermore, global chemical reactivity descriptors were calculated. The degree of second harmonic generation response of the orthorhombic phase of ADMA was found to be 0.22 relative to potassium dihydrogen phosphate. In addition, first-order hyperpolarization susceptibility calculations confirm the nonlinear optical activity of the ADMA crystal. The present study also focuses on the anti-breast cancer activity of ADMA using three breast cancer proteins (Protein Data Bank codes: 5NWH, 5NQR, and 1OQA) by molecular docking studies.