Banca de QUALIFICAÇÃO: BEATRIZ AZEVEDO GALVÃO DE LIMA

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : BEATRIZ AZEVEDO GALVÃO DE LIMA
DATE: 12/12/2025
TIME: 08:30
LOCAL: Auditório do CCET
TITLE:

Novel copper, zinc, and manganese complexes with aminobisnaphthol ligand: spectroscopic, crystallographic, and structural study with prospects for biological application.

KEY WORDS:

Coordination compounds; Copper; Zinc; Manganese; Aminobisnaphthol

PAGES: 145
BIG AREA: Ciências Exatas e da Terra
AREA: Química
SUBÁREA: Química Inorgânica
SPECIALTY: Determinação de Estrutura de Compostos Inorgânicos
SUMMARY:

This work reports the synthesis, characterization, and cytotoxic evaluation against tumor cells of the ligand N,N-bis(2-hydroxynaphthylmethyl)methylamine (H₂L) and three new metal complexes of Cu(II), Zn(II), and Mn(IV). Single-crystal X-ray diffraction revealed a non-iso­structural system. The compounds [Cu(L)]₂ (CuL) and [Zn(L)(CH₃OH)]₂ (ZnL) are binuclear with a double M–Oµ–M bridge, displaying square-planar and distorted trigonal bipyramidal geometries, respectively. The complex [Mn(L)₂] (MnL) is mononuclear with a distorted octahedral geometry. In all cases, the ligand L²⁻ acted in a tridentate fashion (O,N,O)²⁻. Hirshfeld surface analysis complemented the structural elucidation, highlighting intra- and intermolecular interactions responsible for crystal stabilization. The system was characterized by elemental analysis (C, H, N), infrared spectroscopy (IR), UV-Vis spectroscopy, fluorescence spectroscopy, ¹H and ¹³C NMR (1D and 2D, for the ligand), and cyclic voltammetry. Coordination of the naphtholic ligand was confirmed by characteristic νC–O and νC=C bands (1237–1272 cm⁻¹ and 1460–1617 cm⁻¹), as well as δC–H deformations (956–1161 cm⁻¹ and 741–816 cm⁻¹). In the UV-Vis spectra, intraligand π→π* and n→π* transitions were observed (281–356 nm), along with d–d transitions at 407, 478, and 682 nm for CuL, and LMCT transitions at 496 and 595 nm for MnL. Emission spectra showed fluorescence quenching in copper and manganese complexes, while the zinc complex significantly enhanced ligand emission (229 a.u.). Electrochemical studies revealed oxidation processes associated with the ligand, as well as Mn⁴⁺/³⁺ and Mn³⁺/²⁺ redox pairs (E₁/₂: –435 mV) for MnL and Cu²⁺/¹⁺ (E₁/₂: –987.5 mV) for CuL. Cytotoxicity assays against HeLa, A549, and MCF-7 cell lines demonstrated that both the ligand and the complexes induced concentration-dependent cytotoxic effects, with the complexes showing higher activity than the free ligand.

COMMITTEE MEMBERS:
Interno - 1645110 - CARLOS ALBERTO MARTINEZ HUITLE
Externo ao Programa - 2313421 - CARLOS ROBERTO OLIVEIRA SOUTO - nullPresidente - 1715109 - DANIEL DE LIMA PONTES
Externo ao Programa - 1945343 - FRANCISCO ORDELEI NASCIMENTO DA SILVA - null