Structure and peroxidase activity of ferric Streptomyces clavuligerus orf10-encoded protein P450CLA: UV-visible, CD, MCD and EPR spectroscopic characterization

Pentasulfur hexanitride, S5N6, has been prepared in good yield by the reaction of [n-Bu4N+][S4N5−] with bromine (or iodine) in methylene chloride at 0 °C. In contrast, the tetrasulfur pentanitride(−1) ion reacts smoothly with chlorine to give S4N5Cl, while the reaction with sulfuryl chloride produces S4N5Cl and S5N6 and the reaction with thionyl chloride produces a mixture of S3N2O, S3N2O2, S4N4, and S5N6. Pentasulfur hexanitride is an air-sensitive, explosive, yellow-orange solid which sublimes at ca. 45 °C/10−2 Torr without significant decomposition. It has been characterised by infrared, Raman, uv–visible, and mass spectra and by a single crystal X-ray structure determination. The crystals are monoclinic and belong to the space group C2/c, a = 8.787(2), b = 11.190(2), c = 7.427(2) Å, β = 106.46(2)°, V = 700.3(5) Å3, Z = 4, Dc = 2.317 g cm−3. The refined structure (Rw = 0.040) has twofold symmetry and resembles a basket in which an —N=S=N— unit (d(S—N) = 1.54 Å) is the handle which bridges an S4N4 cradle via S—N single bonds (d(S—N) = 1.70 Å). The introduction of this bridge widens one of the [Formula: see text] transannular separations in S4N4 to 3.94 Å while the other is shortened to 2.43 Å. Thus, the S4N4 cradle can be viewed as two five-membered rings fused at the S—S bond.

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Synthesis and NMR Spectroscopic Characterization of Some Fluoro-2H-1-Benzopyran Derivatives

Australian Journal of Chemistry ◽

10.1071/ch05062 ◽

2005 ◽

Vol 58 (7) ◽

pp. 517 ◽

Cited By ~ 4

Author(s):

Yannick Teral ◽

Gabriel Roubaud ◽

Claude Aubert ◽

Robert Faure ◽

Mylène Campredon

Keyword(s):

Mass Spectra ◽

Spectroscopic Characterization ◽

Molecular Probe ◽

Visible Spectroscopy ◽

Chemical Shift Correlation ◽

Photochemical Process ◽

Fragment Ions ◽

Complete Assignment ◽

Uv Visible

The synthesis of some new fluoro-2H-1-benzopyran derivatives utilizing a reaction between titanium phenolates and β-phenylcinnamaldehydes in toluene is reported. These compounds were characterized by NMR and UV/visible spectroscopy as well as mass spectrometry. In solution all the compounds are photochromic. Complete assignment of the 1H and 13C resonances was achieved by concerted application of homonuclear (gs-COSY), proton-detected (C, H) one-bond (gs-HMQC), and long-range (gs-HMBC) heteronuclear two-dimensional chemical shift correlation experiments using a 500 MHz NMR spectrometer equipped with a cryoplatform and a 5 mm cryoprobe. The mass spectra of the different compounds were characterized by intense molecular and high fragment ions. The introduction of an atom of fluorine as a molecular probe is of interest in determining the mechanistic aspects of the photochemical process.

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Manganese(III) and manganese(IV) corroles: synthesis, spectroscopic, electrochemical and X-ray structural characterization

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s1088424605000502 ◽

2005 ◽

Vol 09 (06) ◽

pp. 398-412 ◽

Cited By ~ 27

Author(s):

Zhongping Ou ◽

Christoph Erben ◽

Marie Autret ◽

Stefan Will ◽

Daniel Rosen ◽

...

Keyword(s):

Redox Reactions ◽

Esr Spectroscopy ◽

Spectroscopic Characterization ◽

Axial Ligand ◽

X Ray Diffraction ◽

Nonaqueous Media ◽

X Ray ◽

Cation Radicals ◽

Uv Visible ◽

Electron Reduction

The synthesis, spectroscopic characterization and electrochemistry of four Mn(III) and Mn(IV) octaethylcorroles are reported and the potentials of the Mn(III) / Mn(IV) and Mn(IV) / Mn(III) processes examined as a function of the axial ligand. The investigated compounds are represented as ( OEC ) Mn , ( OEC ) MnCl , ( OEC ) Mn ( py ) and ( OEC ) Mn ( C 6 H 5) where OEC is the trianion of octaethylcorrole. The first one-electron oxidation of ( OEC ) Mn III and ( OEC ) Mn III ( py ) in PhCN or pyridine containing 0.1 M TBAP leads to the facile formation of a Mn(IV) species while the first one-electron reduction of ( OEC ) Mn IV Cl and ( OEC ) Mn IV ( C 6 H 5) in the same two solvents leads to the Mn(III) corrole. All other redox reactions occur at the corrole macrocycle to give π-cation radicals or π-anion radicals and there is no evidence for electrogeneration of a compound with a Mn(II) oxidation state as is the case for manganese(III) porphyrins which are all easily reduced to the Mn(II) state in nonaqueous media. The products of each Mn(III)/Mn(IV) redox reaction were characterized by UV-visible and/or ESR spectroscopy and the structures of ( OEC ) MnCl , ( OEC ) Mn ( py ) and ( OEC ) Mn ( C 6 H 5) were determined by single-crystal X-ray diffraction.

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Synthesis, Spectroscopic Characterization, Antibacterial and Short Term in vitro Cytotoxicity Studies of Copper(II) Complexes of Novel Tridentate N,N,S Donor Ligand 2-Benzoylpyridine-N(4),N(4)-(N,N-diethyl-N-methylamine-2,2'-diyl)thiosemicarbazone

Asian Journal of Chemistry ◽

10.14233/ajchem.2019.22138 ◽

2019 ◽

Vol 31 (10) ◽

pp. 2269-2274

Author(s):

Janey Mary Mathew ◽

Varughese Philip ◽

Jesty Thomas

Keyword(s):

Spectroscopic Characterization ◽

Positive Control ◽

In Vitro Cytotoxicity ◽

Planar Geometry ◽

Blue Dye ◽

Short Term ◽

Donor Ligand ◽

Cytotoxicity Studies ◽

Uv Visible

A tridentate N,N,S-donor ligand, 2-benzoylpyridine-N(4),N(4)-(N,N-diethyl-N-methylamine-2,2'-diyl)thiosemicarbazone (Hbptsc) has been synthesized and characterized by elemental CHN analysis, UV-visible, FT-IR and 1H NMR spectroscopy. Copper(II) complexes of the ligand, Hbptsc synthesized have been characterized by elemental analysis, UV-visible spectra, FTIR spectra and EPR spectroscopic simulation. The complexes hold the stoichiometry of the type [CuLX] where X= Cl (1), NO3 (2), SO4 (3), N3 (4), SCN (5) confirmed by the molar conductivity studies of 10-3 M solutions in DMF at room temperature. The EPR spectra of the complexes recorded in DMF at 77 K shows an axial type spectra with two distinct g-values, g|| and g⊥ indicating a four coordinated planar geometry. The antimicrobial studies of the copper(II) complexes shows an appreciable activity against both gram positive and gram negative bacteria using streptomycin as positive control. The short term in vitro cytotoxicity studies following trypan blue dye exclusion method exhibits pronounced activity against the Dalton’s Lymphoma Ascites tumour cells extruded from the peritoneal cavity of mice.

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Synthesis, characterization, structural exploration and quantum chemical calculations of (E)-8-(1-((4-aminobenzyl)imino)ethyl)-7-hydroxy-4-methyl-coumarin

Oriental Journal Of Chemistry ◽

10.13005/ojc/370231 ◽

2020 ◽

Vol 37 (2) ◽

pp. 484-492

Author(s):

Chethan Prathap K. N ◽

Niranjana S. V ◽

Lokanath N. K

Keyword(s):

Quantum Chemical ◽

Visible Spectrum ◽

Spectroscopic Characterization ◽

Coumarin Derivative ◽

The Novel ◽

Monoclinic Crystal ◽

Supramolecular Architectures ◽

Biological Interest ◽

Uv Visible ◽

Quantum Chemical Dft Calculations

Coumarin derivatives are one of the very important compounds of high biological interest. A novel coumarin derivative (E)-8-(1-((4-aminobenzyl)imino)ethyl)-7-hydroxy-4-methyl-coumarin was synthesized using substituted acetyl coumarin and 4-aminobenzylamine. Following the detailed spectroscopic characterization, the structure of the compound was confirmed using XRD studies. The novel coumarin derivative crystallizes in monoclinic crystal system in P21/c space group and displays diverse intermolecular interactions. One-dimensional array along b-axis and R_2^2 (18) supramolecular architectures are”0 formed mediated by N24—H24…O1 and C17—H17…O10 hydrogen bonds respectively. Hirshfeld surface analysis quantified that H…H, C…H and O…H contacts are the major contributors to the crystal structure with a contribution of 42.9%, 32.7% and 20.1% of total interactions respectively. Further, structural optimization was carried out using quantum chemical DFT calculations that displayed high correlation with XRD structure. The electronic absorption spectrum from TDDFT calculations is matching well with the results of UV-visible spectrum.

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Preparation, Spectroscopic Characterization and Theoretical Studies of Transition Metal Complexes with 1-[(2-(1H-indol-3-yl)ethylimino)methyl]naphthalene-2-ol Ligand

Asian Journal of Chemistry ◽

10.14233/ajchem.2019.21908 ◽

2019 ◽

Vol 31 (11) ◽

pp. 2430-2438 ◽

Cited By ~ 3

Author(s):

Vian Yamin Jirjees ◽

Veyan Taher Suleman ◽

Abbas Ali Salih Al-Hamdani ◽

Suzan Duraid Ahmed

Keyword(s):

Transition Metal ◽

Metal Complexes ◽

Transition Metal Complexes ◽

Spectroscopic Characterization ◽

Bidentate Ligand ◽

Spectroscopic Techniques ◽

Theoretical Studies ◽

Ft Ir ◽

Uv Visible ◽

Methyl Naphthalene

A new Schiff base [1-((2-(1H-indol-3-yl)ethylimino)methyl)naphthalene-2-ol] (HL) has been synthesized by condensing (2-hydroxy-1-naphthaldehyde) with (2-(1H-indol-3-yl)ethylamine). In turn, its transition metal complexes were prepared having the general formula; [Pt(IV)Cl2(L)2], [Re(V)Cl2(L)2]Cl and [Pd(L)2], 2K[M(II)Cl2(L)2] where M(II) = Co, Ni, Cu] are reported. Ligand as well as metal complexes are characterized by spectroscopic techniques such as FT-IR, UV-visible, 13C & 1H NMR, mass, elemental analysis. The results suggested that the ligand behaves like a bidentate ligand for all the synthesized complexes. On the other hand, theoretical studies of the ligand as well its metal complexes were conducted at gas phase using HyperChem 8.0. These metal complexes exhibited good antibacterial activity.

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A haloarchaeal ferredoxin electron donor that plays an essential role in nitrate assimilation

Biochemical Society Transactions ◽

10.1042/bst20110709 ◽

2011 ◽

Vol 39 (6) ◽

pp. 1844-1848 ◽

Cited By ~ 6

Author(s):

Basilio Zafrilla ◽

Rosa María Martínez-Espinosa ◽

María José Bonete ◽

Julea N. Butt ◽

David J. Richardson ◽

...

Keyword(s):

Essential Role ◽

Inorganic Nitrogen ◽

Nitrate Assimilation ◽

Spectroscopic Characterization ◽

Redox Properties ◽

Nitrite Reduction ◽

Plant Type ◽

Uv Visible ◽

Nitrate And Nitrite

In the absence of ammonium, many organisms, including the halophilic archaeon Haloferax volcanii DS2 (DM3757), may assimilate inorganic nitrogen from nitrate or nitrite, using a ferredoxin-dependent assimilatory NO3−/NO2− reductase pathway. The small acidic ferredoxin Hv-Fd plays an essential role in the electron transfer cascade required for assimilatory nitrate and nitrite reduction by the cytoplasmic NarB- and NirA-type reductases respectively. UV–visible absorbance and EPR spectroscopic characterization of purified Hv-Fd demonstrate that this protein binds a single [2Fe–2S] cluster, and potentiometric titration reveals that the cluster shares similar redox properties with those present in plant-type ferredoxins.

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Tungsten and molybdenum oxo complexes of tetrakis(phenyldiazenyl)calix[4]arene substituted derivatives: EHMO calculations, spectroscopic characterization, and perturbations of the photophysical properties by neutral guest molecules

Canadian Journal of Chemistry ◽

10.1139/v96-256 ◽

1996 ◽

Vol 74 (11) ◽

pp. 2279-2288 ◽

Cited By ~ 8

Author(s):

Pierre D. Harvey ◽

Jonathan Gagnon ◽

Réjean Provencher ◽

Bing Xu ◽

Timothy M. Swager

Keyword(s):

Excited States ◽

Photophysical Properties ◽

Binding Constants ◽

Spectroscopic Characterization ◽

Guest Molecules ◽

H Nmr ◽

Oxo Complexes ◽

Visible Luminescence ◽

Uv Visible ◽

Host Chemistry

Bowl-shaped chromophores fabricated with tungsten and molybdenum oxo complexes of calix[4]arenes substituted at the para positions with phenyldiazenyl (R2C6H3N2) derivatives are investigated. The nature of the lowest energy excited states has been addressed theoretically using Extended Hückel Molecular Orbital (EHMO) calculations and experimentally using UV-visible, luminescence, and polarized emission spectroscopy at 77 K. The lowest energy excited states are intraligand (azobenzene fragment) ππ* (S2 and T2) and ππ*states (S1, and T1). The compounds are weakly luminescent in the 600–630 nm range exhibiting emissions arising from the 1(ππ*) states [Formula: see text]. The region located above 900 nm was not investigated. Evidence for guest–host chemistry has been demonstrated by1H-NMR spectroscopy, and the binding constants for two of the compounds with pyridine in toluene as a solvent were obtained by UV–visible spectroscopy. The presence of a guest molecule inside the luminescent metal oxo complex of a calix[4]arene hosts decreases the emission lifetimes.Key words: host–guest, photophysics, calix[4]arene, EHMO, fluorescence

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Electrochemical, spectroelectrochemical and ESR spectroscopic characterization of 2,3- and 3,4-cobalt tetrapyridoporphyrazine isomers in non-aqueous media

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s1088424609001170 ◽

2009 ◽

Vol 13 (08n09) ◽

pp. 876-887 ◽

Cited By ~ 6

Author(s):

Jianguo Shao ◽

Juliette Commodore ◽

Baocheng Han ◽

Cynthia Pruente ◽

Christopher A. Hansen

Keyword(s):

Dimethyl Sulfoxide ◽

Aqueous Media ◽

Spectroscopic Characterization ◽

Spectroscopic Properties ◽

Axial Ligand ◽

Electron Transfer Mechanism ◽

Axial Ligands ◽

Uv Visible ◽

High Concentrations

Two cobalt porphyrazines, 2,3-tetrapyridoporphyrazine and 3,4-tetrapyridoporphyrazine, were examined in N,N-dimethylformamide, dimethyl sulfoxide and pyridine solutions as to their electrochemical, spectroelectrochemical and ESR spectroscopic properties. These results were compared with those of the unsubstituted cobalt phthalocyanine. At high concentrations, aggregation was observed for each investigated compound in the three solvents. The intensity of ESR signals of each derivative depends upon the extent of aggregation in its solution. The g values shift towards high field with an increase in the strength of the axial ligand and the number of axial ligands on the cobalt center. Both tetrapyridoporphyrazine complexes undergo one oxidation and three reductions in N,N-dimethylformamide, dimethyl sulfoxide or pyridine solution. Thin-layer UV-visible spectroelectrochemical results confirmed that the first oxidation and first reduction of both compounds are metal-centered while the second and third reductions are ring-centered. An overall electron transfer mechanism for both porphyrazine derivatives is proposed.

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