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Mamta, Chaudhary A. Novel tetraaza macrocyclic Schiff base complexes of bivalent zinc: microwave-assisted green synthesis, spectroscopic characterization, density functional theory calculations, molecular docking studies, in vitro antimicrobial and anticancer activities. Biometals 2024:10.1007/s10534-024-00616-y. [PMID: 38922505 DOI: 10.1007/s10534-024-00616-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Accepted: 06/10/2024] [Indexed: 06/27/2024]
Abstract
In the present manuscript, novel macrocyclic Schiff base complexes [Zn(N4MacL1)Cl2-Zn(N4MacL3)Cl2] were synthesized by the reaction of ZnCl2 and macrocyclic ligands (N4MacL1-N4MacL3) derived from diketone and diamines under microwave irradiation method and conventional method. The structures of the obtained complexes were identified by various spectrometric methods such as Fourier transformation infra-red (FT-IR), nuclear magnetic resonance (NMR), high-resolution mass spectrometry (HR-MS), powder X-ray diffraction, molar conductivity, and UV-vis. The structures of the synthesized compounds were optimized by using the def2-TZV/J and def2-SVP/J Coulomb fitting basis sets at B3LYP level in density functional theory (DFT) calculations. The macrocyclic Schiff base complexes exhibited higher activities against Gram-positive bacteria (Staphylococcus aureus and Bacillus cereus), Gram-negative bacteria (Escherichia coli and Xanthomonas campestris), and fungal strains (Fusarium oxysporum and Candida albicans) in comparison to macrocyclic Schiff base ligands. Furthermore, the newly synthesized macrocyclic compounds were assessed for their anticancer activity against three cell lines: A549 (human alveolar adenocarcinoma epithelial cell line), HT-29 (human colorectal adenocarcinoma cell line), and MCF-7 (human breast adenocarcinoma cell line) using the MTT assay. The obtained results showed that the macrocyclic complex [Zn(N4MacL3)Cl2] displayed the highest cytotoxic activity (2.23 ± 0.25 µM, 6.53 ± 0.28 µM, and 7.40 ± 0.45 µM for A549, HT-29, and MCF-7 cancer cell lines, respectively). Additionally, molecular docking investigations were conducted to elucidate potential molecular interactions between the synthesized macrocyclic compounds and target proteins. The results revealed a consistent agreement between the docking calculations and the experimental data.
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Affiliation(s)
- Mamta
- Department of Chemistry, Kurukshetra University, Kurukshetra, Haryana, 136119, India
| | - Ashu Chaudhary
- Department of Chemistry, Kurukshetra University, Kurukshetra, Haryana, 136119, India.
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2
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Kant S, Saha S, Lloret F, Cano J, Mukherjee R. A tetracobalt(II) cluster with a two vertex truncated dicubane topology endogenously supported by carboxylate-based (2-pyridyl)methylamine ligands: magneto-structural and DFT studies. Dalton Trans 2023; 52:11922-11933. [PMID: 37574905 DOI: 10.1039/d3dt01131c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/15/2023]
Abstract
A reaction between CoCl2 and L3-(CO2-)2 (2 : 1 stoichiometry) in CH3OH affords a discrete complex [CoII4-{L3-(CO2-)2}2(μ3-OCH3)2(CH3OH)2(H2O)2Cl2] (1) [L3-(CO2-)2 = 3-[N-{2-(pyridin-2-yl)methyl}amino]-bis(propionate)]. The structure of 1 reveals two terminal mononuclear CoII{L3-(CO2-)2}Cl units connected by a dimeric CoII2(μ3-OCH3)2(CH3OH)2(H2O) unit present in the centre through two methoxo (μ3-OCH3)- and two carboxylate (μ-1,1-OCO-) bridges affording a tetranuclear coordination cluster of Co(II) with a defective dicubane topology. In 1, Co1 (terminal) has distorted octahedral CoIIN2O3Cl and the central Co2 has CoIIO6 coordination. Such coordination arrangements afford the observed topology. Variable-temperature magnetic studies reveal anti-ferromagnetic coupling in 1. Three magnetic exchange interactions (one anti-ferromagnetic and two ferromagnetic: J1 = +3.3 cm-1 (Co⋯Co 3.176 Å; μ-1,1-OCO- and μ3-OCH3 bridges), J2 = -2.5 cm-1 (Co⋯Co 3.228 Å; μ-1-OCO- and μ3-OCH3 bridges) and J3 = +10.6 cm-1 (Co⋯Co 3.084 Å; two μ3-OCH3 bridges)) have been identified, with the inclusion of the orbital reduction parameter (α = Aκ = 1.38), spin-orbit coupling (λ = -158 cm-1) and axial distortion (energy gap Δ = -975 cm-1 between singlet and doublet levels), rationalized by density functional theory (DFT) calculations.
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Affiliation(s)
- Shashi Kant
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh 208016, India.
- Department of Chemistry, Bhola Prasad Singh College, Bhore, Gopalganj (Jai Prakash University Chapra), Bihar 841426, India
| | - Sayan Saha
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh 208016, India.
| | - Francesc Lloret
- Departament de Química Inorgànica/Instituto de Ciencia Molecular (ICMOL), Universitat de València, Polígono de la Coma, s/n, 46980 Paterna, València, Spain
| | - Joan Cano
- Instituto de Ciencia Molecular/Departament de Química Inorgànica, Universitat de València, C/Catedrático José Beltrán 2, 46980 Paterna, València, Spain.
| | - Rabindranath Mukherjee
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh 208016, India.
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3
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Shu J, Yue J, Qiu X, Liu X, Ren W, Li Q, Li Y, Xu B, Zhang K, Jiang W. Binuclear metal complexes with a novel hexadentate imidazole derivative for the cleavage of phosphate diesters and biomolecules: distinguishable mechanisms. Inorg Chem Front 2021. [DOI: 10.1039/d1qi00108f] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Oxidative cleavage of phosphate diesters (HPNP, BNPP) is highly faster than the hydrolytic one by binuclear metal complexes with novel imidazole derivative, producing a non-lactone phosphate monoester due to the direct attack of free radicals.
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Affiliation(s)
- Jun Shu
- School of Chemistry and Environmental Engineering
- Sichuan University of Science & Engineering
- Sichuan Zigong 643000
- P. R. China
| | - Jian Yue
- School of Chemistry and Environmental Engineering
- Sichuan University of Science & Engineering
- Sichuan Zigong 643000
- P. R. China
| | - Xin Qiu
- School of Chemistry and Environmental Engineering
- Sichuan University of Science & Engineering
- Sichuan Zigong 643000
- P. R. China
| | - Xiaoqiang Liu
- School of Chemistry and Environmental Engineering
- Sichuan University of Science & Engineering
- Sichuan Zigong 643000
- P. R. China
| | - Wang Ren
- School of Chemistry and Environmental Engineering
- Sichuan University of Science & Engineering
- Sichuan Zigong 643000
- P. R. China
| | - Qianli Li
- College of Chemistry and Chemical Engineering
- Liaocheng University
- Shandong Liaocheng 252059
- P. R. China
| | - Yulong Li
- School of Chemistry and Environmental Engineering
- Sichuan University of Science & Engineering
- Sichuan Zigong 643000
- P. R. China
| | - Bin Xu
- School of Chemistry and Environmental Engineering
- Sichuan University of Science & Engineering
- Sichuan Zigong 643000
- P. R. China
| | - Kaiming Zhang
- School of Chemistry and Environmental Engineering
- Sichuan University of Science & Engineering
- Sichuan Zigong 643000
- P. R. China
| | - Weidong Jiang
- School of Chemistry and Environmental Engineering
- Sichuan University of Science & Engineering
- Sichuan Zigong 643000
- P. R. China
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4
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Chakraborty T, Mukherjee S, Parveen R, Chandra A, Samanta D, Das D. A combined experimental and theoretical rationalization of an unusual zinc(ii)-mediated conversion of 18-membered Schiff-base macrocycles to 18-membered imine–amine macrocycles with imidazolidine side rings: an investigation of their bio-relevant catalytic activities. NEW J CHEM 2021. [DOI: 10.1039/d0nj05635a] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Macrocyclic Zn(ii)-based Schiff base complexes exhibit significant phosphatase-like activity as well as high potential anticancer activity against breast cancer cells.
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Affiliation(s)
| | - Somali Mukherjee
- Department of Chemistry
- University of Calcutta
- Kolkata 700009
- India
| | - Rumana Parveen
- Department of Chemistry
- University of Calcutta
- Kolkata 700009
- India
| | - Arpita Chandra
- In Vitro Carcinogenesis and Cellular Chemotherapy
- Chittaranjan National Cancer Institute
- Kolkata-700026
- India
| | - Debabrata Samanta
- Department of Chemistry
- Dukhulal Nibaran Chandra College
- Aurangabad
- India
| | - Debasis Das
- Department of Chemistry
- University of Calcutta
- Kolkata 700009
- India
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Manda M, Arora H, Sengupta A, Kant S, Lloret F, Mukherjee R. Dimeric Mn( ii), Co( ii), Ni( ii) and Cu( ii) complexes of a common carboxylate-appended (2-pyridyl)alkylamine ligand: structure, magnetism and DFT study. NEW J CHEM 2021. [DOI: 10.1039/d1nj01150b] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Weak anti- (1) and ferro-magnetic (2–4) interactions are observed in [MII2(L3)2(S)2]2+ (Mn 1, Co 2, Ni 3) (S = MeOH) and Cu 4 (S = none).
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Affiliation(s)
- Munirathnam Manda
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur 741 246, India
| | - Himanshu Arora
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208 016, India
- Department of Chemistry, School of Engineering and Sciences, G.D. Goenka University, Gurugram, Haryana 122103, India
| | - Arunava Sengupta
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208 016, India
- Department of Chemistry, Techno India University, West Bengal, Kolkata 700 091, India
| | - Shashi Kant
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208 016, India
- Department of Chemistry, B. P. S. College Bhore, Gopalganj, Bihar 841426, India
| | - Francesc Lloret
- Departament de Química Inorgànica/Instituto de Ciencia Molecular (ICMOL), Universitat de València, Polígono de la Coma, s/n, 46980 Paterna, València, Spain
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Jana NC, Jagličić Z, Brandão P, Adak S, Saha A, Panja A. A novel triple aqua-, phenoxo- and carboxylato-bridged dinickel( ii) complex, its magnetic properties, and comparative biomimetic catalytic studies with analogous dinickel( ii) complexes. NEW J CHEM 2021. [DOI: 10.1039/d1nj00708d] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
A unique triply bridged dinickel(ii) complex and two doubly bridged dinickel(ii) complexes are reported, and their magnetic properties and comparative biomimetic catalytic performances are studied.
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Affiliation(s)
- Narayan Ch. Jana
- Department of Chemistry
- Panskura Banamali College
- Panskura RS
- India
| | - Zvonko Jagličić
- Institute of Mathematics
- Physics and Mechanics & Faculty of Civil and Geodetic Engineering
- University of Ljubljana
- 1000 Ljubljana
- Slovenia
| | - Paula Brandão
- Department of Chemistry
- CICECO-Aveiro Institute of Materials
- University of Aveiro
- 3810-193 Aveiro
- Portugal
| | - Sarmistha Adak
- Department of Chemistry
- Panskura Banamali College
- Panskura RS
- India
- Department of Chemistry
| | - Amrita Saha
- Department of Chemistry
- Jadavpur University
- Kolkata-700032
- India
| | - Anangamohan Panja
- Department of Chemistry
- Panskura Banamali College
- Panskura RS
- India
- Department of Chemistry
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7
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Chowdhury T, Dasgupta S, Khatua S, Acharya K, Das D. Executing a Series of Zinc(II) Complexes of Homologous Schiff Base Ligands for a Comparative Analysis on Hydrolytic, Antioxidant, and Antibacterial Activities. ACS APPLIED BIO MATERIALS 2020; 3:4348-4357. [PMID: 35025433 DOI: 10.1021/acsabm.0c00372] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Six zinc(II) complexes, namely, [Zn(HL1H)Cl2] (1), [Zn(HL1H)Br2] (2), [Zn2(HL1H)2(OH)I2]·I (3), [Zn(HL2)Cl] (4), [Zn2(HL2)Br3] (5), and [Zn(HL2)I] (6) have been manufactured by using two homologous Schiff base ligands H2L1 and H2L2 for the purpose of perlustrating their phosphatase-like activity, antioxidant activity, and antibacterial activity. Complexes 1, 2, 4, and 5 have been reported earlier by us, whereas complexes 3 and 6 have been synthesized and structurally characterized by regular physicochemical methods The hydrolytic property of the six complexes has been evaluated by checking the hydrolysis of the P-O bond of a widely used substrate, namely, disodium salt of (para-nitrophenyl)phosphate (PNPP) in 97.5% (v/v) mixture of N,N-dimethylformamide and water (DMF-water). Complexes 2-5 have profound efficiency toward hydrolysis of phosphate ester bonds, and complexes 1 and 6 were noted to be inactive toward hydrolysis. Complex 3 displayed the highest efficacy among the six complexes. Additionally, antioxidant and antibacterial activities of the complexes were studied thoroughly. A detailed study of their antioxidant property revealed that complex 3 manifested superior radical scavenging activity, thus exhibiting the highest antioxidant property. The antibacterial activity was tested using four investigating bacteria, specifically Listeria monocytogenes ATCC19111, Staphylococcus aureus ATCC 700699, Salmonella typhimurium ATCC 23564, and Escherichia coli ATCC 25922 by determining minimum inhibitory concentration (MIC) values using the microdilution method. Here as well, complex 3 exhibited the highest activity to both Gram positive and Gram negative bacteria. The chemistry behind these experimental findings has been manifested by shedding light upon the structural features of the complexes. The suitable choice of ligand H2L1 where one methylene group is less than its homologous ligand and metal precursor (ZnI2) imparts a unique hydroxo-bridged molecular geometry and 2D hydrogen bonding network which in turn probably enhances the hydrolytic and biological activities of complex 3.
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Affiliation(s)
- Tania Chowdhury
- Department of Chemistry, University of Calcutta, 92, A. P. C. Road, Kolkata 700009, India
| | - Sanchari Dasgupta
- Department of Chemistry, University of Calcutta, 92, A. P. C. Road, Kolkata 700009, India
| | - Somanjana Khatua
- Molecular and Applied Mycology and Plant Pathology Laboratory, Centre of Advanced Study, Department of Botany, University of Calcutta, 35, Ballygunge Circular Road, Kolkata 700019 West Bengal, India
| | - Krishnendu Acharya
- Molecular and Applied Mycology and Plant Pathology Laboratory, Centre of Advanced Study, Department of Botany, University of Calcutta, 35, Ballygunge Circular Road, Kolkata 700019 West Bengal, India
| | - Debasis Das
- Department of Chemistry, University of Calcutta, 92, A. P. C. Road, Kolkata 700009, India
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8
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Experimental and theoretical exploration of sensing and magnetic properties of a triply bridged dicopper(II) complex: The first discrete metal complex to sense picric acid in pure water. J Photochem Photobiol A Chem 2019. [DOI: 10.1016/j.jphotochem.2019.111987] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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9
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Mirdya S, Basak T, Chattopadhyay S. Photocatalytic ability of two hetero-tetranuclear complexes with CuO2Cd cores to degrade methylene blue: Influence of their structures on activity. Polyhedron 2019. [DOI: 10.1016/j.poly.2019.05.043] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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10
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Rajput A, Saha A, Barman SK, Lloret F, Mukherjee R. [Cu II{(L ISQ)˙ -} 2] (H 2L: thioether-appended o-aminophenol ligand) monocation triggers change in donor site from N 2O 2 to N 2O (2)S and valence-tautomerism. Dalton Trans 2019; 48:1795-1813. [PMID: 30644480 DOI: 10.1039/c8dt03778g] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Using a potentially tridentate o-aminophenol-based redox-active ligand H2L1 (2-[2-(benzylthio)phenylamino]-4,6-di-tert-butylphenol) in its deprotonated form, [Cu(L1)2] has been synthesized and crystallized as [CuII(L1)2]·CH2Cl2 (1·CH2Cl2). A cyclic voltammetry experiment (in CH2Cl2; V vs. SCE (saturated calomel electrode)) on 1·CH2Cl2 exhibits two oxidative (E = 0.20 V (peak-to-peak separation, ΔEp = 100 mV) and E = 0.90 V (ΔEp = 140 mV)) and two reductive (E = -0.52 V (ΔEp = 110 mV) and E = -0.92 V (ΔEp = 120 mV)) responses. Upon oxidation using a stoichiometric amount of [FeIII(η5-C5H5)2](PF6), 1·CH2Cl2 yielded [Cu(L1)2](PF6) (2). Structural analysis (100 K) reveals that 1·CH2Cl2 is a four-coordinate bis(iminosemiquinonato)copper(ii) complex (CuN2O2 coordination), and that the thioethers remain uncoordinated. The twisted geometry of 1 (distorted tetrahedral) results in considerable changes in the electronic structure, compared to well-known square-planar analogues. Crystallographic analysis of 2 both at 100 K and at 293 K reveals that it is effectively a four-coordinate complex with a CuN2OS coordination; however, a substantial interaction with the other phenolate O is observed. The metal-ligand bond distances and metric parameters associated with the o-aminophenolate rings indicate a valence-tautomeric (VT) equilibrium involving monocationic (iminosemiquinonato)(iminoquinone)copper(ii) and bis(iminoquinone)copper(i). Complex 1·CH2Cl2 is a three-spin system and a magnetic study (4-300 K) established that it has a S = 1/2 ground-state, owing to the strong antiferromagnetic coupling between the unpaired spin of the copper(ii) and the iminosemiquinonate(1-) π-radical anion. Electron paramagnetic resonance (EPR) spectral studies corroborate this result. Complex 2 is diamagnetic and the existence of VT in 2 was probed using variable-temperature (248-328 K) 1H NMR and EPR (100-298 K) spectral measurements and X-ray photoelectron spectroscopic studies at 298 K. Remarkably, modification of the well-studied 2-anilino-4,6-di-tert-butylphenol by incorporation of a benzylthioether arm leads to the occurrence of VT in 2. The electronic structure of 1·CH2Cl2 and 2 has been assigned using density functional theory (DFT) calculations at the B3LYP-D3 level of theory. Time-dependent (TD)-DFT calculations have been performed to elucidate the origin of the observed UV-VIS-NIR absorptions.
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Affiliation(s)
- Amit Rajput
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208 016, India. and Department of Basic and Applied Sciences, School of Engineering, G. D. Goenka University, Sohna Road, Gurugram 122 103, Haryana, India
| | - Anannya Saha
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur 741 246, India
| | - Suman K Barman
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208 016, India.
| | - Francesc Lloret
- Departament de Quımíca, Inorgànica/Instituto de Ciencia Molecular (ICMOL), Universitat de Valeńcia, Polígono de la Coma, s/n, 46980-Paterna, València, Spain
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11
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Goswami S, Singha S, Saha R, Singha Roy A, Islam M, Kumar S. A bi-nuclear Cu(II)-complex for selective epoxidation of alkenes: Crystal structure, thermal, photoluminescence and cyclic voltammetry. Inorganica Chim Acta 2019. [DOI: 10.1016/j.ica.2018.10.066] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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12
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Dasgupta S, Aullón G, Zangrando E, Das D. Mapping the working route of phosphate monoester hydrolysis catalyzed by copper based models with special emphasis on the role of oxoanions by experimental and theoretical studies. NEW J CHEM 2019. [DOI: 10.1039/c8nj04018d] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The mechanistic pathway of phosphate-ester bond hydrolysis with special emphasis on the role of oxoanions was explored by experimental and theoretical study.
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Affiliation(s)
| | - Gabriel Aullón
- Departament de Química Inorgànica i Orgànica (Secció de Química Inorgànica) and Institut de QuímicaTeorica i Computacional
- Universitat de Barcelona
- 08028 Barcelona
- Spain
| | - Ennio Zangrando
- Department of Chemical and Pharmaceutical Sciences
- University of Trieste
- 34127 Trieste
- Italy
| | - Debasis Das
- Department of Chemistry
- University of Calcutta
- Kolkata 700009
- India
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13
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Rajput A, Sharma AK, Barman SK, Lloret F, Mukherjee R. Six-coordinate [Co III(L) 2] z (z = 1-, 0, 1+) complexes of an azo-appended o-aminophenolate in amidate(2-) and iminosemiquinonate π-radical (1-) redox-levels: the existence of valence-tautomerism. Dalton Trans 2018; 47:17086-17101. [PMID: 30465680 DOI: 10.1039/c8dt03257b] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Aerobic reaction of the ligand H2L1, 2-(2-phenylazo)-anilino-4,6-di-tert-butylphenol, CoCl2·6H2O and Et3N in MeOH under refluxing conditions produces, after work-up and recrystallization, black crystals of [Co(L1)2] (1). When examined by cyclic voltammetry, 1 displays in CH2Cl2 three one-electron redox responses: two oxidative, E11/2 = 0.30 V (peak-to-peak separation, ΔEp = 100 mV) and E21/2 = 1.04 V (ΔEp = 120 mV), and one reductive E1/2 = -0.27 V (ΔEp = 120 mV) vs. SCE. Consequently, 1 is chemically oxidized by 1 equiv. of [FeIII(η5-C5H5)2][PF6], affording the isolation of deep purple crystals of [Co(L1)2][PF6]·2CH2Cl2 (2), and one-electron reduction with [CoII(η5-C5H5)2] yielded bluish-black crystals of [CoIII(η5-C5H5)2][Co(L1)2]·MeCN (3). A solid sample of 1 exhibits temperature-independent (50-300 K) magnetism, revealing the presence of a free radical (S = 1/2), which exhibits an isotropic EPR signal (g = 2.003) at 298 K and at 77 K an eight-line feature characteristic of hyperfine-interaction of the radical with the Co (I = 7/2) nucleus. Based on X-ray structural parameters of 1-3 at 100 K, magnetic and EPR spectral behaviour of 1, and variable-temperature (233-313 K) 1H NMR spectral features of 1-3 and 13C NMR spectra at 298 K of 2 and 3 in CDCl3 point to the electronic structure of the complexes as either [CoIII{(LAP)2-}{(LISQ)}˙-] or [CoIII{(L1)2}˙3-] (delocalized nature favours the latter description) (1), [CoIII{(LISQ)˙-}2][PF6]·2CH2Cl2 (2) and [CoIII(η5-C5H5)2][CoIII{(LAP)2-}2]·MeCN (3) [(LAP)2- and (LISQ)˙- represent the redox-level of coordinated ligands o-amidophenolate(2-) ion and o-iminobenzosemiquinonate(1-) π-radical ion, respectively]. Notably, all the observed redox processes are ligand-centred. To the best of our knowledge, this is the first time that six-coordinate complexes of a common tridentate o-aminophenolate-based ligand have been structurally characterized for the parent 1, its monocation 2 and the monoanion 3 counterparts. Temperature-dependent 1H NMR spectra reveal the existence of valence-tautomeric equilibria in 1-3. Density Functional Theory (DFT) calculations at the B3LYP-level of theory corroborate the electronic structural assignment of 1-3 from experimental data. The origins of the observed UV-VIS-NIR absorptions for 1-3 have been assigned, based on time-dependent (TD)-DFT calculations.
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Affiliation(s)
- Amit Rajput
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208 016, India.
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14
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Das B, Daver H, Pyrkosz-Bulska M, Gumienna-Kontecka E, Himo F, Nordlander E. An Unsymmetric Ligand with a N5
O2
Donor Set and Its Corresponding Dizinc Complex: A Structural and Functional Phosphoesterase Model. Eur J Inorg Chem 2018. [DOI: 10.1002/ejic.201701416] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Biswanath Das
- Chemical Physics; Department of Chemistry; Lund University; Box 124 22100 Lund Sweden
| | - Henrik Daver
- Department of Organic Chemistry; Arrhenius Laboratory; Stockholm University; 106 91 Stockholm Sweden
| | - Monika Pyrkosz-Bulska
- Faculty of Chemistry; Arrhenius Laboratory; University of Wroclaw; F. Joliot-Curie Street 14 50-383 Wroclaw Poland
- Institute of Chemistry; Arrhenius Laboratory; University of Silesia; Szkolna 9 40-006 Katowice Poland
| | - Elzbieta Gumienna-Kontecka
- Faculty of Chemistry; Arrhenius Laboratory; University of Wroclaw; F. Joliot-Curie Street 14 50-383 Wroclaw Poland
| | - Fahmi Himo
- Department of Organic Chemistry; Arrhenius Laboratory; Stockholm University; 106 91 Stockholm Sweden
| | - Ebbe Nordlander
- Chemical Physics; Department of Chemistry; Lund University; Box 124 22100 Lund Sweden
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15
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Neelakantan M, Balakrishnan C, Balamurugan K, Mariappan S. Zinc(II)-N 2
O 2
ligation complex-based DNA/protein binder and cleaver having enhanced cytotoxic and phosphatase activity. Appl Organomet Chem 2018. [DOI: 10.1002/aoc.4400] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- M.A. Neelakantan
- Chemistry Research Centre; National Engineering College; K. R. Nagar, Kovilpatti - 628 503 Thoothukudi District Tamil Nadu India
| | - C. Balakrishnan
- Chemistry Research Centre; National Engineering College; K. R. Nagar, Kovilpatti - 628 503 Thoothukudi District Tamil Nadu India
| | - K. Balamurugan
- Chemistry Research Centre; National Engineering College; K. R. Nagar, Kovilpatti - 628 503 Thoothukudi District Tamil Nadu India
| | - S.S. Mariappan
- Chemistry Research Centre; National Engineering College; K. R. Nagar, Kovilpatti - 628 503 Thoothukudi District Tamil Nadu India
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16
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Joshi P, Hussain N, Ali SR, Rishu R, Bhardwaj VK. Enhanced activity of trinuclear Zn(ii) complexes towards phosphate ester bond cleavage by introducing three-metal cooperativity. NEW J CHEM 2018. [DOI: 10.1039/c7nj03759g] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The catalytic efficiency (DNA binding followed by phosphate ester bond cleavage) of Zn(ii) complexes has been tuned by variation in the nuclearity, flexibility and coordination environment to explore the structure activity correlation.
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Affiliation(s)
- Pooja Joshi
- Department of Chemistry
- D.S.B. Campus
- Kumaun University
- Nainital
- India
| | - Navid Hussain
- Department of Chemistry
- Indian Institute of Technology Ropar
- Rupnagar
- India
| | - Shah Raj Ali
- Department of Chemistry
- D.S.B. Campus
- Kumaun University
- Nainital
- India
| | - Rishu Rishu
- Department of Chemistry
- MCM DAV College for Women
- Chandigarh-160036
- India
| | - Vimal K. Bhardwaj
- Department of Chemistry
- Indian Institute of Technology Ropar
- Rupnagar
- India
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17
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Chakraborty T, Dasgupta S, Zangrando E, Das D. Portraying the role of halo ligands and the auxiliary part of ligands of mononuclear manganese(iii)-Schiff base complexes in catalyzing phospho–ester bond hydrolysis. NEW J CHEM 2018. [DOI: 10.1039/c8nj02634c] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The influences of the auxiliary part of ligands and halo ligands have been explored towards phosphatase like activity using a series of manganese(iii)-Schiff base complexes as catalysts.
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Affiliation(s)
| | | | - Ennio Zangrando
- Department of Chemical and Pharmaceutical Sciences
- University of Trieste
- 34127 Trieste
- Italy
| | - Debasis Das
- Department of Chemistry
- University of Calcutta
- Kolkata 700009
- India
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