Multifaceted Study of a Y-Shaped Pyrimidine Compound: Assessing Structural Properties, Docking Interactions, and Third-Order Nonlinear Optics

Abstract

In this study, we report the synthesis of a new compound, N4,N4-dimethyl-2-(methylsulfanyl)-N6-(4phenoxyphenyl)pyrimidine-4,6-diamine (DMS), and its comprehensive analysis through structural and spectroscopic characterizations, reactivity parameters, and nonlinear optical properties, utilizing a combination of experimental and computational techniques. The experimental aspect of the investigation encompassed structural characterization using X-ray diffraction and spectroscopic assessments employing Fourier-transform infrared, Raman, and nuclear magnetic resonance techniques, along with thermal analysis. Our computational approach involved density functional theory (DFT) calculations and molecular dynamics (MD) simulations to examine the local reactivity properties of DMS. We employed fundamental reactivity descriptors to evaluate DMS's local reactivity and utilized MD simulations to identify DMS atoms engaging in significant interactions with water molecules. We conducted periodic DFT calculations on DMS's crystal structure to investigate the contributions of specific atoms and groups to the compound's overall stability as well as to analyze noncovalent interactions between DMS molecules. We assessed the nonlinear optical properties through dynamic second hyperpolarizability and third-order nonlinear susceptibility calculations. Additionally, we conducted a comparative analysis of the static and dynamic second hyperpolarizability for the DMS molecule within the sum-over-states framework. The obtained value for the third-order nonlinear susceptibility, 3 = 65.41 10 20 × m /V 2 2 (λ = 1907 nm), exceeds those of other organic materials reported in previous studies, indicating that the DMS crystal holds promise as a nonlinear optical material for potential application in photonic device fabrication. Furthermore, molecular docking studies were performed with the 3E5A, 4EUT, and 4EUU proteins, yielding binding affinities of −8.1, −8.2, and −8.3 kcal/ mol, respectively, in association with the ligand.