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Several Imines (Schiff bases) have been reported for their significant biological activity. In this work, an imine, (E)-1-(3-bromobenzylidene)-2-phenylhydrazine has been synthesized under microwave irradiation and evaluated for its antioxidant activity by DPPH assay. The structure of synthesized compound was confirmed based on the spectroscopic data included UV-Vis, FT-IR, MS, 1D and 2D NMR. Based on the DPPH assay, the synthesized compound possessed a strong antioxidant activity with IC50 value of 62 μg/ml. [ABSTRACT FROM AUTHOR]

A Schiff base of E-4-(((1H-indol-3-yl)methylene)amino)-N-(pyrimidin-2-yl)benzene sulfonamide (IMAPB) were synthesized and characterized by FT-IR, ¹H & 13C NMR, Mass spectroscopy. Uv-vis spectroscopic measurement probe IMAPB of absorption band 296 nm was observed. The fluorescence intensity at 428 nm was obtained due to turn-on chemosensors for selectivity and sensitivity of Pb2+ ion with the interference of other metal ions. The stoichiometric of 1:1 complex formation of IMAPB+Pb2+ to confirmed association constant value at 2.3×10−4 M−1 (R²=0.94976). The PET mechanism was binding with IMAPB+Pb2+ linked nitrogen and oxygen. Competitive metal ions to select Pb2+ metal ions compared other metal ions. EDTA solution binding of IMAPB+Pb2+ with result fluorescence ON, however, different pH range was used in probe of IMAPB+Pb2+. The cytotoxicity activity of IMAP used different concentration used HeLa cells. [ABSTRACT FROM AUTHOR]

A Schiff base of E-4-(((1H-indol-3-yl)methylene)amino)-N-(pyrimidin-2-yl)benzene sulfonamide (IMAPB) were synthesized and characterized by FT-IR, ¹H & 13C NMR, Mass spectroscopy. Uv-vis spectroscopic measurement probe IMAPB of absorption band 296 nm was observed. The fluorescence intensity at 428 nm was obtained due to turn-on chemosensors for selectivity and sensitivity of Pb2+ ion with the interference of other metal ions. The stoichiometric of 1:1 complex formation of IMAPB+Pb2+ to confirmed association constant value at 2.3×10−4 M−1 (R²=0.94976). The PET mechanism was binding with IMAPB+Pb2+ linked nitrogen and oxygen. Competitive metal ions to select Pb2+ metal ions compared other metal ions. EDTA solution binding of IMAPB+Pb2+ with result fluorescence ON, however, different pH range was used in probe of IMAPB+Pb2+. The cytotoxicity activity of IMAP used different concentration used HeLa cells. [ABSTRACT FROM AUTHOR]

Schiff base play an important role in the development of Coordination Chemistry as they readily form stable coordination compounds with most of the transition metal ions. They are synthesized from the condensation of an amino compound with carbonyl compounds. This review article compiles most promising applied Schiff bases and their complexes with their applications in different areas of life. These coordination compounds have been characterized on the basis of elemental analyses, molecular weight, molar conductance, spectral (IR, reflectance, ¹H NMR, ESR) and magnetic susceptibility measurements. The coordination compounds widely used as catalyst in various reactions. They also show excellent biological activities like antiinflammatory, scavenging, analgesic, antibiotic, antioxidative, antifungal, antibacterial, antiviral and enzymaticactivities. This review summarizes the chemistry and application of metal Schiff bases complexes. [ABSTRACT FROM AUTHOR]

Three new complexes containing salicylaldazine (HL) ligand were synthesised by reacting suitable precursor complex [MCl2(PPh3)2] with the ligand (where M = Cu(II) or Ni(II) or Co(II)).The new complexes were characterised by various spectral studies such as IR, UV--Vis, ¹H NMR, EPR, fluorescence and elemental analyses. The binding modes of the complexes with HS-DNA have been studied by UV--Vis absorption titration. Binding of the complexes with bovine serum albumin (BSA) protein has been investigated using UV-visible, fluorescence and synchronous fluorescence spectroscopic methods. Redox behaviour of the complexes has been investigated by cyclic voltammetry. [ABSTRACT FROM AUTHOR]

A series of novel (-)-gossypol Schiff bases and hydrazones have been synthesized via an in-situ procedure in high yields. Structural data showed that all target compounds existed in enamine conformation. The bioassay result displayed that several compounds exhibited cytotoxic effects against three human cancer cell lines including HepG2, LU- 1 and MCF-7 with IC50 values of 16.56, 10.75 and 7.44 µg/mL, respectively. In antibacterial test, some compounds also inhibited Staphylococcus aureus and Bacillus cereus at the same MIC values of 1024 µg/ml. [ABSTRACT FROM AUTHOR]

Novel Zinc (II) metal complexes of Schiff base were prepared by the condensation of Zinc (II)) with Isatin Hydrazone and 2-Hydroxy Naphthaldehyde. Characterization of the new complexes was done by elemental analysis, conductance measurement, IR, UV, NMR and Mass spectral studies, thermal studies and microbial activities. The studies indicate that the ligand acts as a tridentate chelating ligand coordinating through oxygen and nitrogen atoms. Tetrahedral geometry is proposed for all the complexes by the analysisof the results of spectral, thermal and elemental analysis. All the new complexes show potent bacteriosides than the ligand. [ABSTRACT FROM AUTHOR]

The diorganotin(IV) complexes of the type Me2SnL, Bu2SnL and Ph2SnL (L) with the anion of the semicarbazone ligand formed by condensation reaction of 3,4-dihydroxybenzaldehyde with semicarbazide were synthesized using 1:1 metal to ligand reactant ratios. The newly synthesized complexes were characterized using elemental analysis, infrared and nuclear magnetic resonance (¹H, 13C, 119Sn) spectroscopic techniques. Complex formation between the organotin(IV) moiety and the anion of 3,4-dihydroxybenzaldehysemicarbazone occurred with chelation at the o-dihydroxy positions. The complexes were proposed to have tetrahedral geometry. [ABSTRACT FROM AUTHOR]

A novel hydroxynaphthaldehyde derived Schiff base ligand N,N'-bis-[2-[(2-hydroxy-1- naphthyl)methyleneamino]ethyl]propanediamide (DOTA2HNAP) containing nitrogen and oxygen donor atoms has been developed. The lowest energy molecular structure of DOTA2HNAP and its complexes with Cu (II) metal ion were examined by molecular mechanics using MM+ force which later was re-optimized by semi-empirical method. The theoretical IR and UV spectra of the ligand were obtained using semi empirical/ZINDO/PM3 and were compared with the experimental ones. The coordinating ability of DOTA2HNAP with H+ and Cu(II) ions was investigated in 1:99 (DMSO: water) binary solvent mixture at 25±1°C by potentiometric and spectrophotometric method. The electronic spectra of the ligand show three distinct peaks (253nm, 320nm and 360nm) implicating existence of the Schiff base in quinone form that was well supported by theoretical spectral studies. Out of various complex species forming in solution, all the metal ions show higher stability of complexes when in 1:1 metal-ligand stoichiometry, binding through two N-imine and two O-naphtholate groups. [ABSTRACT FROM AUTHOR]

Two new mono nuclear Fe(III) complexes of an azodye (ANSN) and a Schiff base (FAHP) are reported. The azodye is prepared by coupling diazotized l-amino-2-naphthol-4-sulphonicacid with 2-naphthol and the Schiff base is prepared by condensing 2- amino-3-hydroxy pyridine with furfural. The complexes were synthesized by the reaction of FeCb.2H20 with respective ligands. They were characterized on the basis of elemental analysis and spectral studies like IR, NMR, Electronic and Mössbauer. Magnetic susceptibility and Molar conductance of complexes at room temperature were studied. Based on the spectroscopic evidences and other analytical data the complexes are formulated as[Fe(ANSN)Cl(H20)2] and [Fe(FAHP)Cl2(H20)2] [ABSTRACT FROM AUTHOR]

A series of novel metal complexes of Schiff base have been prepared by the interaction of Cu(II) with isatin salicylic hydrazide. All the new compounds were characterized by elemental analysis, conductance measurement, magnetic moment determination, IR, UV, NMR, Mass and EPR spectral studies, thermal studies and microbial activities. The results indicate that the ligand acts as a tridentate chelating ligand coordinating through nitrogen and oxygen atoms. The ligand and complexes show inactive against Escherichia coli and active against Staphylococcus aureus and B.substilis. By analyzing the results of spectral, thermal and elemental analysis square planar geometry is proposed for all the complexes. [ABSTRACT FROM AUTHOR]

A new Schiff base was prepared from o-vanillin and acetazolamide followed by synthesis of di- and triorganotin(IV) complexes of the general formula RnSn(L)m and R'nSn(L)m [R = n-Bu, n = 2, m = 2; R' = n-?u, n = 3, m = 1; HL =Schiff base| by green methodology using microwaves. The synthesized complexes were characterized by elemental analysis and UV-Visible, IR and multinuclear (¹H, 13C, 119Sn) NMR Spectroscopic studies. [ABSTRACT FROM AUTHOR]

Five Chromium (III) complexes have been prepared using Schiff base ligands which derived from benzoin and five different amino acids (H2N-R). Samples were characterized by XRD, FTIR, UV-VIS and SEM method. X-Ray diffraction pattern analyzed that all chromium (III) complexes have hexagonal structure and crystalline, in nature, using Bruker D8 Advance instrument. Using VERTAX 70, FTIR spectroscopy reveals that Samples have (C=N), (C-O), (M-N) and (M-O) bonds in the range of 4000-400cm"¹. UV-VIS spectroscopy give information that samples absorb the visible light which is in the range of 380-780nm. For this, Lambda 960 spectrometer used. SEM is designed for studying of the solid objects, using JEOL JSM 5600 instrument. [ABSTRACT FROM AUTHOR]

The crystal structures of 1-(3,4,5-trimethoxybenzylidene)thiosemicarbazide (1) and N'-(3-nitrobenzylidene) isonicotinohydrazide (2) have been determined by single-crystal X-ray diffraction. In compound 1, the position of C8, O1, O2, O3 atoms are in a distorted trigonal planar geometry. The mean plane of 3,4,5-trimethoxybenzylidene ring forms a dihedral angle of 5.39(14)° with the mean plane of thiosemicarbazide group. In the structure, the molecular packing is stabilized by intermolecular N-H··N, O-H··S and intramolecular C-H··O hydrogen bonds. In compound 2, the position of C8 atom and N1 atom are in a distorted trigonal planar geometry. The mean plane of phenyl ring forms a dihedral angle of 8.09° with that of the pyridine ring. In the structure, the molecular packing is stabilized by intermolecular N-H··N and intramolecular C-H··O hydrogen bonds. [ABSTRACT FROM AUTHOR]

The title compound, (Z)-1-(3-chlorophenyl)-4[1{(2hydroxyphenyl)amino}propylidene]-3-methyl-1H-pyrazol-5(4H)- one was synthesized by refluxing compound 1-(m-chlorophenyl)-3-methyl-4-propionyl-5-pyrazolone, with 2-aminophenol in ethanol. The compound crystallizes in the orthorhombic crystal system with space group Pca21 having unit cell parameters: a = 26.2993(8), b = 7.0724(2) and c = 18.7170(5)Å .The structure contains two crystallographically independent molecules, A, and, B, in the asymmetric unit cell. The crystal structure was solved by direct method using single crystal X-ray diffraction data collected at room temperature and refined by full-matrix least-squares procedures to a final R- value of 0.049 for 5207 observed reflections. [ABSTRACT FROM AUTHOR]

Lead-210 is one of the highly radiotoxic metals reaching the water supplies from nuclear power plants and mines. The chelating ability of Schiff bases enhances their application as a new adsorbent material for the removal of several toxic metals and their radioisotopes. In this study, multi-walled carbon nanotubes were modified using bis-N,N'-u(salicylidene)-1,3-diaminopropane and bis-N,N'(salicylidene)-1,3-diaminopropane- Cu(II). Schiff bases used for the modification of the multi-walled carbon nanotubes were syntheses according to our previous study [1]. The obtained SB-MWCNTs was characterized by scanning electron microscopy (SEM) analysis. The prepared adsorbent was used to adsorb lead (II) ions in aqueous solution. Various parameters such as adsorbent dose, initial pH, contact time and different initial concentration of lead (II) ions which influenced the adsorption capacity were investigated. [ABSTRACT FROM AUTHOR]