29 research outputs found
ON THE DIOXIMINE COMPLEXES OF TRANSITION METALS, Part XC NEW AZIDO-COMPLEX ACIDS OF COBALT(III) WITH ALICYCLIC α-DIOXIMES
Four new diazido-complex acids of the type H[Co(Diox.H)2(N3)2] (Diox.H2 = alicyclic
α-dioximes: Cpdox.H2, Niox.H2, Heptox.H2 and Octox.H2) and the
H[Co(Niox.H)2(N3)(NO2)] were obtained by air oxidation of the components and by sub-
stitution reactions. The free acids and their salts were characterized by IR and electronic
spectra and by potentiometric measurements. The composition of the azido-derivatives
was proved also by isolation of 30 new salts with cobalt(III)- and chromium(III)- amine bases
ON THE OXIMINE COMPLEXES OF TRANSITION METALS. PART CXVIII. STUDY ON THE PROTOLYTIC EQUILIBRIA IN THE SOLUTIONS OF MIXED CHELATES OF THE TYPE [Co(Diox.H)2AB]n WITH ALICYCLIC α-DIOXIMES1
16 new chelate compounds of the type
[Co(Diox.H)2AB]n (Diox.H2-alicyclic α-dioxime with
C5..C8 in the hydroaromatic ring, A, B monodentate ligands: NCO-,
NO2-, S2O32-, NH3, pyridine, aromatic amine) were obtained by
air oxidation of the components and by various substitution reactions,
respectively. The complexes were characterized by FTIR spectra. The complicated
protolytic equilibria with the participation of the intramolecular
O-H..O hydrogen bridges of the Co(Diox.H)2 moieties
were studied by spectrophotometric and potentiometric measurements
ON THE DIOXIMINE COMPLEXES OF TRANSITION METALS. XCV. NEW IODO-AMINO-BIS-DIMETHYLGLYOXIMATO-COBALT(III)-NONELECTROLYTES
New nonelectrolytic type chelate compounds of cobalt(III) with the general formula [Co(DH)₂IA)] DH-monodeprotonated dimethylglyoxime, A -different aromatic and heterocyclic amines and tertiary phosphines) were obtained by means of a substitution reaction from the diiodo-bis-dimethylglyoximato-cobaltiat and the corresponding amines and phosphines in alcoholic-aqueous media. The nonelectrolytes are sparingly soluble in water and soluble in some organic solvents, e.g. CHCl₃, DMFA, DMSO, etc. These derivatives were characterized by lR and electronic spectra, and in several cases by derivatographic measurements
Entropy measures and predictive recognition as mirrored in gating and lexical decision over multimorphemic Hungarian noun forms
Our paper is an attempt to indicate the relevance of information theoretical accounts
to understand word recognition and morphological processing in Hungarian, along with other
studies using more traditional predictors like linear position and morphological composition.
The first two experiments were gating studies. The effect of the decision points was only
evident in frequent words. The correct recognition means for the recognition points differ
from the means for one-before-recognition points, indicating that the recognition point
follows a sudden drop of the entropy value. This shows how entropy measures can be used to
predict word recognition in actual language performance. The next two experiments examined
the word reconstruction effect. A clear bathtub effect (Aitchison, 1987) was obtained:
reconstruction was highest in the cases where both the beginning and the end were correct.
The last, lexical decision based study used four basic morphological types of markers (plural,
second and first possessive) and three types of case (-nak,-ban-,-ra ‘DAT, INSIDE, ONTO).
The main effect of the frequency and the error type was significant. Frequent words were judged faster but less accurately, suggesting a trade-off. The later the mistake is, the faster and easier its rejection was
Novel cobalt complexes with glyoximes : synthesis, physicochemical analysis and biological study
Azomethine derivatives have several applications, especially as reagents for the determination of transition metal ions. Furthermore these ligands and their cobalt complexes were also reported to possess biological activities, such as antimicrobial, anti-tubercular, anticonvulsant, anti-inflammatory, anti-proliferative activities as well as antifungal inhibition potential [1]. Another reason for using metal-containing compounds as structural scaffolds is related to the kinetic stability of their coordination spheres in the biological environment. Metallic ions have been shown to play important role in the biological activity of different compounds in such away that, in some cases, activity is enhanced or only takes place in the presence of these ions [2]. In our research new cobalt(III) complexes were synthesized with -glyoximes, azides, amines, thiocyanate and halogens, such as [Co(Me-propyl-GlyoxH)2(N3)(amine)], [Co(Mepentyl-GlyoxH)2(N3)(amine)], [Co(Et-propyl-GlyoxH)2(N3)(amine)], [Co(Et-propylGlyoxH)2(Br)(amine)], [Co(Et-propyl-GlyoxH)2(SCN)(amine)], H[Co(Et-propylGlyoxH)2(SCN)2], [Co(phenyl-Me-GlyoxH)2(amine)2]I, [Co(Et-propyl-GlyoxH)2(amine)2]I, [Co(Et-Bu-GlyoxH)2(amine)2]I, where GlyoxH = mono deprotonated glyoxime, and the used amines: imidazole, 3-hydroxy-aniline, lepidine, 3,5-dimethyl-pyridine, di(n-butyl)-amine, diisopropyl-amine, 2-amino-pyrimidine, diphenyl-amine, 2-picoline, 3-picoline. The Co(II)- acetate salt dissolved in water and mixed with the glyoxime alcoholic solution was oxidized by air bubbling, then the corresponding diamines and the other complexing agents were added. The molecular structure of our products was investigated by IR, UV–VIS spectroscopy, mass spectrometry (MS), thermoanalytical measurements (TG-DTG-DTA), and powder XRD. The biological activity, like antimicrobial effect, was studied for a few bacteria
ON THE DIOXIMINE COMPLEXES OF TRANSITION METALS. PART XCVII. a-SUBSTITUTED OXIME DERIVATIVES IN THE SPECTROPHOTOMETRIC DETERMINATION OF COBALTl
The formation conditions, composition, stability and analytical application of some ternary
complexes: Co(II):11:X=1:2:2(11=aJiphatic and alycyclic a-dioximes; X=N;-, 1-),
binary derivatives: Co(II):12 =a-ketoximes: diacetylmonoxime, methyl-isopropyl dione
monoxime, 1,2,3-cyclohexane trione dioxime (1,3)), Co(II): 1 3=1:2 (13 =condensation
products of ketoximes with semicarbazide, thiosemicarbazide) and Co(II):14=Schiff's
bases with ethylenediamine and hydrazine) were studied spectrophotometrically. The
electronic spectra of these complexes were recorded and discussed
Novel platinum complexes with schiff bases and α-Dioximes, their physico-chemical and biological study
In our research project we prepared the following platinum(II) complexes with Schiff bases and -dioximes, such as [Pt(ketone)2A(L2)], (ketone: 2-heptanone, 2-octanone, 3-octanone; A: hydrazine, phenylhydrazine, o-phenylene-diamine; L: 1-naphthylamine, 2-aminopyrimidine, 2-methylimidazole, 2-amino-4-methylpyridine) and [Pt(DioxH)2L2], (DioxH2: methyl-phenyl-dioxime, butyl-methyl-dioxime; L: 1-naphthylamine, 2-methylimidazole, 2-amino-4-methylpyridine, lepidine, 2-methylpyridine, m-toluidine, dicyclohexylamine, 4-isopropylamine, cyclohexylamine), by the reaction of PtCl2 in suitable solvent. After a short bibliographical survey, involving the classification and evolution of platinum complexes with possible applications, we analyzed their physico-chemical properties using FTIR, Raman, NMR, UV-VIS spectroscopy, powder X-ray diffraction (XRD), mass spectrometry, thermal analysis (TG, DTG, DTA) and SEM. We also studied the antibacterial effect of complexes on different strains of bacteria. This class of compounds has relevance in biochemistry, some of them are antibacterial agents and potential anti-tumor drugs
Synthesis, physico-chemical characterization and bacteriostatic study of Pt complexes with substituted amine ligands
Three complexes of general formula PtCl2R2 were synthesized, where R is the amine ligand with aromatic substituents. Coordination compounds [Pt(an)2Cl2] (1), [Pt(pa)2Cl2] (2) and [Pt(aph)2Cl2] (3), where an = 2-aminonaphthalene, pa = 2-aminopyrimidine, aph = 4-anilinophenol, were characterized by on-line coupled TG/DTA-MS, powder XRD and spectroscopic techniques (FTIR, ESI–MS and NMR), and tested against selected Gram(+) and Gram(–) bacteria. The thermal data show that all three compounds contain lattice or absorbed water, and the stability of the anhydrous compounds in nitrogen decreases in the order 2 > 1 > 3. Above 200 °C, the complexes loose characteristic fragments of their ligands. The spectroscopic data are in accordance with the thermal properties of the samples and prove their composition. The compounds are more effective inhibitors of Gram(+) than Gram(−) bacteria. © 2016 Akadémiai Kiadó, Budapest, Hungar
Novel iron complexes with glyoximes, schiff bases and boric acid derivatives : synthesis, physico-chemical analysis and biological study
Iron(II) clathrochelate complexes obtained with glyoximes are macrobicyclic ligand systems, which completely encapsulate the metal ion, and are formed under mild conditions with high yields [1]. In particular, the riblike-functionalized clatrochelates both with the inherent and with the terminal closo-borate substituents synthesized recently have been proposed as new radiopharmaceuticals for boron neutron capture therapy of cancer [2]. In our research work new iron(II) complexes were synthesized with -glyoximes, boric acid derivatives, amines, Schiff bases, such as [Fe(Me-Pr-Glyox)3(BO–Et)2], [Fe(Et-BuGlyox)3(BO–R)2] (R = methyl, propyl, butyl), [Fe(phenyl-Me-GlyoxH)2(amine)2], [Fe(Et-BuGlyoxH)2(amine)2], [Fe(2-heptanone)2(en)(amine)2], where GlyoxH, Glyox = mono- or bideprotonated glyoxime, en = ethylenediamine and the used amines: dibutylamine, 3-picoline, 4-aminopyridine, 6-amino-3-picoline, 3-amino-1-propanol, imidazole, 2-aminopyrimidine, 3- methylpiperidine, 3-amino-1H-1,2,4-triazole. For preparation ironII -sulfate was dissolved in water and mixed with alcoholic solution of the glyoxime, then the corresponding amines and the other complexing agents were added. The mixture so obtained was refluxed under inert atmosphere. The molecular structures of our products were studied by IR, Mössbauer and UV–VIS spectroscopies, mass spectrometry (MS) and thermoanalytical measurements (TG-DTG-DTA). The biological activity, like antimicrobial effect, was studied for a few bacteria