A fluorescent biosensor based on acetylcholine sterase and 5-oxazolone derivative immobilized in polyvinylchloride (PVC) matrix

A new 2-phenyl-4-[4-(1,4,7,10-tetraoxa-13-azacyclopentadecyl)benzylidene]-5-oxazolone (CPO) derivative was utilized to develop an optical acetylcholinesterase (AChE) biosensor in which the azlactone derivative was embedded in plasticized polyvinylchloride (PVC) matrix. The sensor system was calibrated for the detection of acetylcholine (ACh) and donepezil which is a competitive cholinesterase (ChE) inhibitor. Two different biosensing systems were developed by using AChE enzyme in solution and immobilized together with the fluorescent derivative (CPO) doped in transparent PVC membrane. The enzymatic hydrolysis of ACh was monitored by following changes in the pH induced fluorescence intensity. When AChE enzyme was immobilized in PVC matrix together with CPO, the sensitivity of the measuring system has increased approximately three times for ACh, in comparison to the sensing system where AChE enzyme was in solution phase

Fluorescence emission studies of 4-(2-furylmethylene)-2-phenyl-5-oxazolone embedded in polymer thin film and detection of Fe3+ ion

The photophysical and photochemical properties of azlactone derivative 4-(2-furylmethylene)-2-phenyl-5-oxazolone (PFO) were examined in solvents of tetrahydrofuran (THF), acetonitrile (ACN) and dichloromethane (DCM) and in solid matrix of polyvinyl chloride (PVC)

Synthesis and spectroscopic properties of new 5-oxazolone derivatives containing an N-phenyl-aza-15-crown-5 moiety

Novel 5-oxazolone derivatives containing an N-phenyl-aza-15-crown-5 moiety were synthesized for the first time. The structures of the new derivatives were confirmed by H-1 NMR, C-13 NMR and FT-IR. In addition, evaluation of the visible absorption and emission properties of the structures were carried out in eight different solvents. The products show intense visible absorption maxima in the range 467-524 nm, and fluoresced strongly, with emission maxima from 496 to 689 nm in all the solvents tested. (c) 2007 Elsevier Ltd. All rights reserved

Synthesis and Characterization of New Y-shaped Fluorophores with an Imidazole Core

Four new y-shaped fluorophores of 4- {4,5-[2,2'-Bis(2,4,6-trimethoxyphenyl)vinyl]-1-H-imidazole-2-yl}benzonitrile 1a, 2-phenyl-{4,5-[2,2'-Bis(2,4,6-trimethoxyphenyl)vinyl]-1-H-imidazole} 1b, 2- (9-anthryl)-{4,5-[2,2'-Bis(2,4,6-trimethoxyphenyl)vinyl] }-1-H-imidazole 1c and 2- (4-nitrophenyl) - {4,5-[2,2'-Bis(2,4,6-trimethoxyphenyl)vinyl] -1-H-imidazole 1d which bear an imidazole core, were synthesized for the first time via intermediate 1,6-Bis(2,4,6-trimethoxyphenyl)hexa-1,5-diene-3,4-dion with different aldehydes. The structures of the new derivatives were confirmed by H-1 NMR, C-13 NMR and FT-IR. The optical properties such as absorption and emission maxima, Stokes' shift and quantum yield values were investigated in solvents of toluene, tetrahydrofuran and acetonitrile. The products show intense emission maxima in the range of 440-630 nm. The imidazole derivatives exhibited excellent photostabilities

2-Methoxy-4-[(5-oxo-2-phenyl-4,5-dihydro-1,3-oxazol-4-ylidene)methyl]-phenyl 4-methylbenzenesulfonate

Molecules of the title compound, C24H19NO6S, adopt the Z configuration and have a distorted tetrahedral geometry around the S atom. The oxazolone, 2-phenyl and methoxyphenyl rings are approximately coplanar. The C atom between the methoxyphenyl and oxazolone rings displays a distorted trigonal bonding geometry. Pairs of molecules are linked into dimers through weak C - H center dot center dot center dot O hydrogen bonds

Fluorescence Properties and Electrochemical Behavior of Some Schiff Bases Derived from N-Aminopyrimidine

A series of Schiff bases (L (1) , L (2) and L (3) ) were prepared by refluxing aromatic aldehydes with N-Aminopyrimidine derivatives in methanol and ethanol. The structures of synthesized compounds were characterized by FTIR, H-1 NMR, C-13 NMR and microanalysis. The electrochemical behaviors of the Schiff base ligands were also discussed. Moreover, the evaluation of absorption and emission properties of the structures were carried out in five different solvents. The products show visible absorption maxima in the range of 304-576 nm, and emission maxima from 636 to 736 nm in all solvents tested

STRUCTURAL AND PHOTOPHYSICAL CHARACTERIZATION, TOPOLOGICAL AND CONFORMATIONAL ANALYSIS OF 2-o-TOLYL-4-(3-N,N-DIMETHYLAMINOPHENYLMETHYLENE)-OXAZOL-5-ONE

A novel oxazole-5-one derivative 2-o-tolyl-4-(3-N,N-dimethylaminophenylmethylene)-oxazol-5-one (TDPO) C19H18N2O2 is synthesized and characterized and the crystal structure is determined by X-ray crystallography. TDPO is monoclinic in the P2(1)/c space group. The molecule adopts the Z configuration. To enlighten the flexibility of TDPO, the selected torsion angle is varied from -180 degrees to 180 degrees in each 10 degrees separately, and the molecular energy profile is calculated and analyzed by density functional calculations. In addition, Bader's QTAIM analysis is performed to investigate the intramolecular weak interactions

Transition Metal(II) Complexes of a Novel Symmetrical Benzothiazole-Based Ligand: Synthesis, Spectral/Structural Characterization and Fluorescence Properties

2,6-bis (benzothiazol-2-yl)-4-(tert-butyl) phenol ligand (HL) derived from o-aminothiophenol and 4-tert-butyl-2,6-diformylphenol was synthesized and characterized by using elemental analysis, FTIR, X-ray crystallographic analysis, H-1 and C-13-NMR and UV-vis spectra. Its complexes with Cu (II), Ni (II) and Co (II) were prepared and isolated as solid products and characterized by elemental analysis, spectral techniques as well as magnetic susceptibility. The FTIR spectra showed that the benzothiazole-based ligand under investigation behaves as a bidentate ligand. The UV-vis spectra and magnetic moment data suggested an octahedral geometry around Ni (II) and Co (II) complexes, and tetragonal geometry for Cu (II) complex. Moreover, the evaluation of absorption and emission properties of the ligand and its complexes were carried out in different solvents. The ligand and its complexes showed absorption maxima in the range of 275 - 432 nm, and emission maxima from 367 to 581 nm in toluene, tetrahydrofuran and ethyl acetate

Synthesis of Novel Carbazolyl-Oxazolone Derivatives and Their Spectroscopic Properties

Novel carbazolyl-oxazolones, 3a-d, were synthesized with 3-[N-(2-hydroxycarbonylmethyl)-carboxamide]-4-methyl-9H-carbazole and several aryl aldehydes for the first time. Photo physical characterization of synthesized 2-carbazolyl-4-arylidene-5-oxazolones (3a-d) in dichloromethane, chloroform, and toluene was performed

Crystal Structure and Conformational Analysis of 4-[(p-N,N-Dimethylamino) benzylidene]-2-(3,5-dinitrophenyl)oxazole-5-one

An azlactone derivative, 4-[(p-N,N-dimethylamino)benzylidene]-2-(3,5-dinitrophenyl)oxazol-5-one (DNPO), C18H14N4O6, has been synthesized, and its crystal structure has been investigated by single crystal X-ray analysis and ab initio method. DNPO is monoclinic, with a=9.3628(4), b=13.5148(9), c=13.7701(6), =92.921(4), Z=4, Dx=1.46g/cm3, (MoK)=0.112mm-1, and space group P 121/c1. The whole molecule is almost planar. The crystal structure is stabilized by C-HN type intramolecular, C-HO type intermolecular interactions. To determine the flexibility of DNPO, the selected torsion angle is varied from-180 to 180 in steps of 10, and the molecular energy profile is calculated and analyzed