Synthesis, crystal structure, Hirshfeld surface analysis and DNA binding studies of 1-((E)-3-(4-bromophenyl)-1-phenylallylidene)-2-(m-tolyl)hydrazine

摘要

1-((E)-3-(4-bromophenyl) -1-phenylallylidene)-2-(m-tolyl)hydrazine (4) was synthesized and characterized for structural elucidation by spectroscopy (FT-IR, H-1 NMR, and C-13 NMR) and single crystal X-ray diffraction. In the title compound, the benzene rings A, B, C were oriented at dihedral angles {A/B = 82.92 (3)degrees, A/C = 24.12 (3)degrees and B/C = 75.90 (3)degrees}. Crystal structure showed that intermolecular C-H center dot center dot center dot O and C-H center dot center dot center dot N hydrogen bonds linked the molecules, enclosing R-2(2) (10) and R-2(2) (16) ring motifs. The Hirshfeld surface analysis of the crystal structure indicated that the most important contributions for the crystal packing were from H center dot center dot center dot H (46.0%), H center dot center dot center dot C/C center dot center dot center dot H (17.6%), H center dot center dot center dot Br/Br center dot center dot center dot H (12.4%), H center dot center dot center dot O/O center dot center dot center dot H (8.5%) and C center dot center dot center dot C (6.6%) interactions. Hydrogen bonding and van der Waals contacts were the dominant interactions in the crystal packing. Compound's interaction with DNA was further investigated theoretically by DFT and experimentally by UV-visible spectroscopy and cyclic voltammetry. DFT analysis in terms of geometry optimization and computed parameters revealed reactive nature of 4 and the possibility of planar phenyl rings to intercalate within the DNA base pairs. Spectral and voltammetric analysis and related binding parameters suggested intercalation as a possible mode for 4 - DNA binding which was further verified by viscosity measurements. (C) 2019 Elsevier B.V. All rights reserved.