Guilherme B Laranjeira

Bio: Guilherme B Laranjeira is an academic researcher from Federal University of Mato Grosso do Sul. The author has contributed to research in topics: Infrared spectroscopy & Coordination geometry. The author has an hindex of 1, co-authored 1 publications receiving 4 citations.

Harvesting greenish blue luminescence in gold(I) complexes and their application as promising bioactive molecules and cellular bioimaging agents

Abstract: Three novel highly photoluminescent mononuclear AuI compounds (1, 2, and 3) based on mixed phosphine/thiocarbamoyl-pyrazoline materials were synthesized at good yields using a sonochemical method and then structurally characterized. X-ray diffraction studies revealed the compounds to be mononuclear cationic complexes of the [Ph3PAu(L)]PF6 type with linear coordination geometry around AuI atoms. Investigation of photophysical properties showed an intense greenish blue emission when the complexes were excited at 305 nm in solution. The emission was attributed to mixed MLCT + IL and LLCT electronic transitions taking place after ligand complexation, as shown by DFT calculations. Full characterization of the compounds also comprised 1H and 13C NMR experiments, elemental analyses, infrared spectroscopy, and absorption–emission studies. Additionally, compounds 1, 2, and 3 and respective ligands were investigated as antibacterial agents against five Streptococcus aureus strains (Gram-positive) and one Escherichia coli strain (Gram-negative) with distinct antibiotic-resistance profiles. Cytotoxic activity was assessed using the MTT method against B16F10 melanoma, 4T1 mammary carcinoma, and normal BHK-21 baby hamster kidney cell lines. The synthesized AuI compounds proved more active than the respective precursors and free ligands. Tested as probes for cellular bioimaging, the complexes showed good biodistribution in the cytoplasm of MCF-7 and MDA-MB-231 (human breast adenocarcinoma cell lines).

Synthesis, crystal structure, Hirshfeld surface analysis and molecular docking analysis of new cadmium(II) iodide complex with the pyridine, 4-(1,1-dimethylethyl)

Abstract: Abstract This study was set out to introduce a newly synthesized cadmium complex, [Cd(4-tertbutyl-pyridine)2I2], where t-BP = 4-tert-butyl pyridine. The complex was synthesized and characterized using elemental analysis, X-ray diffraction, FTIR, and photoluminescence combined with DFT calculations. The X-ray analysis of (Cd(t-BP)2I2) revealed that the Cd center is approximately tetrahedrally coordinated with two nitrogen atoms from the 4-tertbutylpyridine groups and the two I ions forming an approximately tetrahedral geometry with τ4 = 0.89. The presence of various intermolecular interactions and 2 D-fingerprint regions is supported by the Hirshfeld surface analysis. In the theoretical calculations, the density functional theory (DFT) method with the PBEPBE functional, the SDD basis set for Cd and I, and the 6-311 G(d) basis set for C, N, and H at the B3LYP/LANL2DZ level were chosen as the computational method. Systems based on electronic and optical properties were also discussed. The frontier molecular orbitals (FMO) analysis, chemical activity, local reactivity descriptors (Fukui functions), and NLO properties were examined for the compound at the LANL2DZ level of theory. The Cd(II) complex was studied by using molecular docking analysis to identify the active site and binding energies with anti-cancer receptors.