Synthesis and Characterization of Mononuclear Copper(II), Cobalt(II) and Nickel(II) Chelates with New Bidentate Aromatic Schiff Bases

Tümer, Mehmet; Köksal, Hüseyin; Serın, Selahattın

doi:10.1080/00945719708000226

Cited by 38 publications

(2 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…p* transitions [2 -6,16] the first with those of the benzene ring and the second with those of the imino group. [12,16,17] 1 H NMR Spectra From the 1 H NMR spectra, and IR absorption peaks of -OH groups binding metal ions in complexes, it is thought that the -OH groups are trans-to each other. p* transition is shifted to a longer wavelength as a consequence of coordination when binding with the metal, confirming the formation of Schiff base metal complexes.…”

Section: Electronic Spectramentioning

confidence: 99%

Spectroscopic and Conductance Studies of New Transition Metal Complexes with a Schiff Base Derived from 4‐Methoxybenzaldehyde and 1,2‐bis(p‐Aminophenoxy)ethane

Çakır

Temel

İhan

et al. 2003

Spectroscopy Letters

View full text Add to dashboard Cite

Four new metal complexes of Cu(II), Ni(II), Zn(II) and Co(III) with Schiff base derived from 4-methoxybenzaldehyde and 1,2-bis( p-aminophenoxy)ethane have been prepared and characterized by magnetic susceptibility, conductance measurements, elemental analyses, UV -Vis, H NMR and IR spectra studies. The magnetic and spectroscopic data indicate an octahedral geometry for the six-coordinate complexes. The ligand was used for complexation studies. Stability constants were measured by means of a conductometric method. Furthermore, the stability constants for complexation between ZnCl 2 , Cu(NO 3 ) 2 and AgNO 3 salts and ligand (L) in 80% dioxane -water and pure methanol were determined from conductance measurements. In 80% dioxane -water, the stability constants (log Ke) increase inversely with the crystal radii in the order Ag(I) < Zn(II) < Cu(II).

show abstract

Section: Electronic Spectramentioning

confidence: 99%

Spectroscopic and Conductance Studies of New Transition Metal Complexes with a Schiff Base Derived from 4‐Methoxybenzaldehyde and 1,2‐bis(p‐Aminophenoxy)ethane

Çakır

Temel

İhan

et al. 2003

Spectroscopy Letters

View full text Add to dashboard Cite

show abstract

“…As transições de transferência de carga para o metal, LMCT (π→dπ), são observadas em bandas na região próxima do visível e são de intensidade um pouco menor. As bandas na região do visível, de intensidade ainda mais baixa, referem-se às transições do metal, d-d, que usualmente não são permitidas pelas regras de Laporte ou de spin.Para os complexos de base Schiff, as transições LT são referentes aos gruposcromóforos C=N e C=C, e aparecem na região UV até cerca de 300 nm 73. As bandas referentes à transição LMCT aparecem entre 320 e 450 nm, aproximadamente.…”

unclassified

Complexos de cobre com análogos de produtos naturais encontrados em organismos marinhos com atividade antitumoral

Tofik¹

View full text Add to dashboard Cite

Neste trabalho foram sintetizados complexos de cobre(II) com derivados imínicos da isatina, incluindo isatinas bromadas semelhantes a compostos encontrados em gastrópodes, a fim de compará-los com o composto já produzido e investigado [Cu(isaepy)], complexo de cobre(II) com base de Schiff feita a partir da isatina e 2-aminoetilpiridina. A isatina é um oxindol produzido em algumas plantas, também encontrado no tecido de mamíferos, com propriedades antitumorais naturais. Isatinas bromadas foram previamente constatadas como mais citotóxicas frente a células tumorais do que a isatina sem substituições. O objetivo principal foi verificar se a presença de bromo nos compostos análogos ao [Cu(isaepy)] levaria a um aumento da atividade antitumoral, assim como maior interação com DNA, alvo usual de metalofármacos. Depois de sintetizados, os compostos foram caracterizados por análise elementar (CHN), espectroscopia no infravermelho, espectroscopia UV/Vis e EPR. Foram feitos testes de citotoxicidade pelo método MTT com células de sarcoma uterino (MES-SA e MES-AS/Dx5, esta última resistente a doxorrubicina), adenocarcinoma cervical (HeLa) e células não cancerosas de fibroblasto humano P4. Adicionalmente, foram feitos testes de interação com DNA por UV/Vis e dicroísmo circular, além de testes de clivagem de DNA plasmidial. De modo geral, foi demonstrado que a simetria tetragonal em torno do cobre, determinada pelo EPR, é importante para a citotoxicidade dos complexos, que dessa forma podem se intercalar ao DNA e impedir sua replicação, por acabar distorcendo a hélice, e pela habilidade de realizarem clivagem oxidativa das fitas. [Cu(isaepy)] e seus análogos bromados demonstraram uma atividade citotóxica muito parecida, assim como grau de interação e clivagem com DNA. Conclui-se que, embora a presença de bromo nos análogos de [Cu(isaepy)] não levem a um aumento de atividade antitumoral, como observado em ligantes correlatos livres, nossos estudos apontam para diferentes fontes naturais (animal ou vegetal) para obtenção de precursores de novos compostos antitumorais. Palavras-chave: oxindóis; iminas; complexos de cobre; atividade antitumoral; DNA. ABSTRACT Tofik, V. F. Copper complexes with analogues of natural products found in marine organisms with antitumor activity. 2018. 73p. Master's Thesis -Graduate Program in Biochemistry. Instituto de Química, Universidade de São Paulo, São Paulo.In the present work, copper(II) complexes were synthesized with isatin derived imine ligands, including brominated oxindoles similar to compounds found in gastropods, in order to compare their reactivity with that of [Cu(isaepy)], a Schiff base-copper(II) complex already investigated, obtained with the precursors isatin and 2-aminoethylpyridine. Isatin is a natural oxindole extracted from plants, and also found in mammal tissue, with antitumor properties. Brominated isatins were previously described as much more cytotoxic, towards tumor cells, than unsubstituted isatin. The aim of this work was to verify if the presence of brome in analogue [Cu...

show abstract

Synthesis, characterization, in vitro antimicrobial and cytotoxic studies of Co(II), Ni(II), Cu(II), and Zn(II) complexes obtained from Schiff base ligands of 1, 2, 3, 4‐tetrahydro‐naphthalen‐1‐ylamine

Devi

Sharma

Kumar

et al. 2022

Applied Organom Chemis

View full text Add to dashboard Cite

The transition metal complexes of Co(II), Ni(II), Cu(II) and Zn(II) with bidentate Schiff base ligands (HL1−5) were obtained from condensation of 1, 2, 3, 4‐tetrahydro‐naphthalen‐1‐ylamine with methanolic solution of 3‐hydroxy‐salicylaldehyde, 4‐hydroxy‐salicylaldehyde, 5‐bromo‐salicylaldehyde, 3,5‐dibromo‐salicylaldehyde, and 2‐hydroxy‐1‐napthaldehyde. The synthesized compounds were structurally elucidated by spectral and physical methods. The spectral characterization emphasized bidentate nature (NO) of Schiff base ligands which gets chelated with metal via nitrogen atom of imine group and deprotonated oxygen of salicylaldehyde/2‐hydroxy‐1‐napthaldehyde group to form octahedral geometry around metal atom. Thermal results supported that the complexes are stable upto 200°C leaving metal oxide as an end products. The reported compounds (1–25) in this series were screened against the bacterial strains, that is, two Gram positive: Bacillus subtilis and Staphylococcus aureus, two Gram negative: Pseudomonas aeruginosa and Escherichia coli, and two fungal strains: Candida albicans and Aspergillus niger and their results that indicated moderate to good activity with compounds 20 and 21 having good antimicrobial activity (minimum inhibitory concentration [MIC] value 0.0269–0.0067 μmol/ml) as compared with control drugs ciprofloxacine and fluconazole. Furthermore, cytotoxic studies of synthesized compounds were carried out against three human cancer cell lines: HCT‐116 (colon), A549 (alveolar), and MCF‐7 (breast) using standard drug paclitaxel. The results demonstrated that compounds 1 (IC50 values = 12.93, 15.13, 17.24), 3 (11.9, 9.29, 12.64), 9 (17.06, 20.06, 22.87), 14 (16.21, 18.47, 20.00), and 25 (17.54, 17.21, 20.23) for three cancer cell lines were found to be most potent candidates among the synthesized compounds.

show abstract

Synthesis and Characterization of Mononuclear Copper(II), Cobalt(II) and Nickel(II) Chelates with New Bidentate Aromatic Schiff Bases

Cited by 38 publications

References 14 publications

Spectroscopic and Conductance Studies of New Transition Metal Complexes with a Schiff Base Derived from 4‐Methoxybenzaldehyde and 1,2‐bis(p‐Aminophenoxy)ethane

Spectroscopic and Conductance Studies of New Transition Metal Complexes with a Schiff Base Derived from 4‐Methoxybenzaldehyde and 1,2‐bis(p‐Aminophenoxy)ethane

Complexos de cobre com análogos de produtos naturais encontrados em organismos marinhos com atividade antitumoral

Synthesis, characterization, in vitro antimicrobial and cytotoxic studies of Co(II), Ni(II), Cu(II), and Zn(II) complexes obtained from Schiff base ligands of 1, 2, 3, 4‐tetrahydro‐naphthalen‐1‐ylamine

Contact Info

Product

Resources

About