scholarly journals Tautomeric Equilibrium of Salicylidene Schiff Base. UV-Visible Absorption and Raman Spectroscopic Studies

1986 ◽  
Vol 59 (9) ◽  
pp. 2897-2898 ◽  
Author(s):  
Ho-hi Lee ◽  
Teizo Kitagawa
Keyword(s):  
Schiff Base ◽  
Spectroscopic Studies ◽  
Tautomeric Equilibrium ◽  
Visible Absorption ◽  
Raman Spectroscopic ◽  
Uv Visible

Raman Spectroscopic Studies of Titanium Alkoxides Using UV Excitation

1986 ◽  
Vol 73 ◽  
Author(s):  
Mark J. Payne ◽  
Kris A. Berglund
Keyword(s):  
Spectroscopic Studies ◽  
Excitation Wavelength ◽  
Raman Signal ◽  
Titanium Alkoxides ◽  
Visible Absorption ◽  
Raman Spectroscopic ◽  
Low Concentrations ◽  
Raman Enhancement ◽  
Uv Visible ◽  
Uv Excitation

ABSTRACTThe use of Raman spectroscopy can be greatly hindered by the presence of fluorescing impurities. Even at low concentrations, fluorescence can completely obscure the Raman signal. In the current study, Raman spectra were recorded for various titanium alkoxides (ethoxide, isopropoxide, isobutoxide) as a function of concentration and laser excitation wavelength. It has been shown that fluorescence can be avoided by using uv-excitation (363.8 nm). In addition, titanium alkoxides exhibit a preresonance Raman enhancement as the excitation wavelength appreaches the UV. This result is confirmed by a uv-visible absorption spectrum of the isopropoxide.

scholarly journals Spectroscopic studies on the interaction of hypocrellin A with myoglobin

2007 ◽  
Vol 21 (4) ◽  
pp. 235-243 ◽  
Author(s):  
J. H. Zhou ◽  
X. H. Wu ◽  
C. Yang ◽  
X. T. Gu ◽  
L. Zhou ◽  
...  
Keyword(s):  
Binding Sites ◽  
Spectroscopic Analysis ◽  
Spectroscopic Studies ◽  
Interaction Process ◽  
Quenching Mechanism ◽  
Visible Absorption ◽  
Paramagnetic Resonance ◽  
Hypocrellin A ◽  
Uv Visible ◽  
Electron Paramagnetic

Experimental results of UV-visible absorption spectroscopy and fluorescence spectroscopy indicate that hypocrellin A, which has been studied in photodynamic therapy, can interact with the surface of myoglobin through hydrophobic forces, and form a complex. Based on the Stern–Volmer equation, the quenching constants of the process can be calculated to be 4.81×1012L mol−1s−1(t=25°C) and 4.54×1012L mol−1s−1(t=42°C) respectively, and the binding constant is 5.53×104M−1(t=25°C), while the binding sites is 0.94 (t=25°C). In addition, Electron paramagnetic resonance and fluorescence spectroscopic analysis suggests that that the quenching mechanism of the interaction process occurs through the electron transfer between hypocrellin A and myoglobin.

scholarly journals Synthesis and Characterization of New Palladium(II) Schiff Base Complexes Derived from β-Diketones and Diamines

2020 ◽  
Vol 32 (5) ◽  
pp. 1039-1042
Author(s):  
Mridula Gupta ◽  
Sheela M. Valecha
Keyword(s):  
Schiff Base ◽  
Schiff Base Complexes ◽  
Schiff Base Ligands ◽  
Visible Absorption ◽  
Oh Groups ◽  
Uv Visible ◽  
Coordinated Water ◽  
Heterocyclic Schiff Bases ◽  
Phenolic Oh Groups

A new series of heterocyclic Schiff bases were prepared from condensation of 1-phenyl-3-methyl-4-acetyl/benzoyl-pyrazolone with 4,4′-diaminodiphenylmethane and 4,4′-diaminodiphenyl ether, resulting in the formation of four novel Schiff base ligands. These ligands were then treated with ethanolic solution of PdCl2, to form corresponding palladium(II) complexes. These complexes were characterized by elemental analysis, IR, 1H NMR, TGA, magnetic susceptibility measurements and UV-visible absorption spectroscopy. All the Pd(II) complexes were found to have one coordinated water molecule. Schiff base ligands chelated with the metal atom through two donor sites N and O of azomethine (-C=N-) and phenolic (-OH) groups, respectively.

Raman Spectroscopic Studies of Amsacrine

1992 ◽  
Vol 46 (10) ◽  
pp. 1540-1544 ◽  
Author(s):  
Catherine A. Butler ◽  
Ralph P. Cooney ◽  
William A. Denny
Keyword(s):  
Crystal Structure ◽  
Raman Spectroscopy ◽  
Crystal Structure Data ◽  
Visible Spectrum ◽  
Spectroscopic Studies ◽  
Resonance Raman Spectrum ◽  
Raman Spectroscopic ◽  
Ft Raman Spectroscopy ◽  
Uv Visible ◽  
Ft Raman

Amsacrine (4′-(9-acridinylamino)methanesulfon- m-anisidide) in both solid and aqueous forms was characterized with the use of resonance and nonresonance Raman spectroscopy (including FT-Raman spectroscopy). Evidence that the acridine nucleus is the dominant chromophoric unit contributing to the resonance Raman spectrum is based upon the apparent similarities of the spectra of aqueous amsacrine (in the unpro-tonated form) and acridine (in ethanol). The probable non-coplanarity of the acridine and phenyl units in the amsacrine molecule (based on previously reported crystal structure data) is consistent with the suggestion that the acridine nucleus may constitute an independent chromophoric unit. Further evidence is derived from analysis of the UV-visible spectrum, which indicates that excitation at 457.9 nm falls within an electronic transition of the acridine nucleus of amsacrine. The excitation profiles of aqueous amsacrine are presented, and four types of profiles have been identified.

Spectroscopic Studies of the Interaction of 1,4-Diphenyl-1,3-Butadiene with α-, β-, and γ-Cyclodextrins

1997 ◽  
Vol 51 (2) ◽  
pp. 153-159 ◽  
Author(s):  
Arsenio Muñoz de la Peña ◽  
Rezik A. Agbaria ◽  
Montserrat Sánchez Peña ◽  
Isiah M. Warner
Keyword(s):  
Fluorescence Emission ◽  
Spectroscopic Studies ◽  
Visible Absorption ◽  
Spectral Shifts ◽  
Equilibrium Reaction ◽  
High Anisotropy ◽  
Spectroscopic Characteristics ◽  
Uv Visible ◽  
High Absorption ◽  
Absorption Measurements

Steady-state fluorescence, anisotropy, and UV-visible absorption measurements have been used to investigate the structure and spectroscopic characteristics of the complexes formed by trans, trans-1,4-diphenyl-1,3-butadiene (DPB) with α-, β-, and γ-cyclodextrins (CDs). The behavior of α-CD with DPB is very different from that of DPB with respect to β-CD or γ-CD. In the presence of α-CD, clear solutions with high absorption and fluorescence emission, relatively high anisotropy, a rapid equilibrium reaction, and Benesi–Hildebrand plots lead us to conclude that normal 2:1 inclusion compounds are formed. In the presence of γ-CD, turbid solutions, with absorption and fluorescence emission intensities lower than those in α-CD, higher values of anisotropy, slow equilibrium reaction, and spectral shifts to the red in the absorption, excitation, and emission wavelengths are evidence of the formation of extended linear aggregates. In the presence of β-CD, both mechanisms of inclusion appear to be present.

UV-Visible and Raman Spectroscopic Studies of Lithocholic Acid on E-2-Butenal for AntiGlioma

2015 ◽  
Vol 48 (7) ◽  
pp. 506-513 ◽  
Author(s):  
Bo Zhang ◽  
Yanbin Su ◽  
Lei Chen ◽  
Zhuofu Wu ◽  
Fengrong Zhang ◽  
...  
Keyword(s):  
Lithocholic Acid ◽  
Spectroscopic Studies ◽  
Raman Spectroscopic ◽  
Uv Visible

scholarly journals Synthesis, Spectroscopic and Electrochemical Studies of Mononuclear Fe(II) and Ni(II) Complexes Containing a Macrocyclic Ligand Derived from Pyridine-2,6-dicarboxaldehyde and 1,2-Bis(2-aminoethoxy) Ethane

2011 ◽  
Vol 3 (3) ◽  
pp. 599-607 ◽  
Author(s):  
M. M. Alam ◽  
R. Begum ◽  
S. M. M. Rahman ◽  
S. M. S. Islam
Keyword(s):  
Schiff Base ◽  
Macrocyclic Ligand ◽  
Nickel Complexes ◽  
Spectroscopic Studies ◽  
Octahedral Geometry ◽  
Electrochemical Studies ◽  
Metal Source ◽  
Elemental Analyses ◽  
Uv Visible ◽  
Metal Perchlorate

The cyclic (2+2) template condensation of 2,6-pyridinedicarboxaldehyde with 1,2-bis(2-aminoethoxy) ethane using Pb(SCN)2 as the metal source gave dinuclear lead(II) complex, Pb2L1(SCN)4 (1), where L1 is tetra-Schiff-base macrocycle. The transmetallation treatment of 1 with suitable metal perchlorate yield [FeL1](ClO4)2 (2) and [NiL1](ClO4)2 (3). The complexes (2 & 3) have been characterized by elemental analyses, IR, UV-visible, and ESI-MS spectroscopy. Based on spectral data, octahedral geometry may be proposed for these complexes. The electrochemical behavior of iron and nickel complexes is reported.Keywords:  Macrocyclic complexes; Spectroscopic studies; 1,2-Bis(2-aminoethoxy) ethane; Charge transfer.© 2011 JSR Publications. ISSN: 2070-0237 (Print); 2070-0245 (Online). All rights reserved.doi: 10.3329/jsr.v3i3.7231               J. Sci. Res. 3 (3), 609-617 (2011)

The UV-visible action-absorption spectrum of all-trans and 11-cis protonated Schiff base retinal in the gas phase

2018 ◽  
Vol 20 (10) ◽  
pp. 7190-7194 ◽  
Author(s):  
Jeppe Langeland Knudsen ◽  
Anika Kluge ◽  
Anastasia V. Bochenkova ◽  
Hjalte V. Kiefer ◽  
Lars H. Andersen
Keyword(s):  
Absorption Spectrum ◽  
Schiff Base ◽  
Gas Phase ◽  
Visible Absorption ◽  
Base Form ◽  
Uv Visible ◽  
Visible Action

The UV-visible absorption of retinal in its protonated Schiff-base form is studied in the gas-phase.

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