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1.
Artigo em Inglês | MEDLINE | ID: mdl-19162535

RESUMO

The reaction of tribenzyltin(IV) chloride and di(para-chlorobenzyl)tin(IV) dichloride with thiohydrazones derived by condensation of 2-phenylethyl N-thiohydrazide with benzaldehyde, salicaldehyde, p-methylacetophenone and cinnamaldehyde have been investigated in 1:1 molar ratio. These ligands act as neutral, bidentate species and coordinate to the central tin (IV) atom through the thiosulphur and azomethine nitrogen. The newly synthesized complexes have been characterized by elemental analysis and molecular weight determination. The mode of bonding of the complexes has been suggested on the basis of infrared, electronic and (1)H NMR spectroscopy, and probable structures have been assigned to these complexes. Phenomenological and kinetic parameters have been calculated using thermogravimetric (TG) and differential thermal analytical (DTA) curves and their variations have been correlated with some structural parameters of the complexes. The ligands and their tin(IV) complexes have been screened in vitro for their fungicidal activity against Rhizoctonia solanii and Sclerotium rolfsii and found to be quite active in this respect.


Assuntos
Antifúngicos , Hidrazonas/química , Compostos Orgânicos de Estanho , Antifúngicos/química , Antifúngicos/farmacologia , Fungos/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Compostos Orgânicos de Estanho/química , Compostos Orgânicos de Estanho/farmacologia , Temperatura
2.
Artigo em Inglês | MEDLINE | ID: mdl-17631043

RESUMO

Nickel(II) complexes of type [Ni(L)(2)Cl(2)] and [Ni(L)(2)(OCOCH(3))(2)], where L=N,N-diphenyl-N-thiohydrazide (L(1)) and (N,N-diphenyl-N-thio)-1,3-propanediamine (L(2)), have been synthesized. The thiodiamines coordinate as a bidentate N-S ligand. The synthesized nickel(II) complexes of the thiodiamines were characterized by elemental analysis, IR, mass, electronic and (1)H NMR spectroscopic and TG/DTA studies. Various kinetic and thermodynamic parameters like order of reaction (n), activation energy (E(a)), apparent activation entropy (S(#)) and heat of reaction (DeltaH) have also been carried out for one complex. These complexes were also screened for in vitro antifungal and in vitro antibacterial activities and significant activity have been found.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Diaminas/química , Diaminas/síntese química , Difenilamina/análogos & derivados , Hidrazinas/química , Hidrazinas/síntese química , Níquel/química , Compostos Organometálicos/química , Compostos Organometálicos/síntese química , Tioureia/análogos & derivados , Antibacterianos/síntese química , Antibacterianos/química , Antifúngicos/síntese química , Antifúngicos/química , Bactérias/efeitos dos fármacos , Análise Diferencial Térmica , Difenilamina/síntese química , Difenilamina/química , Elétrons , Fungos/efeitos dos fármacos , Cinética , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Espectrofotometria Infravermelho , Temperatura , Termogravimetria , Tioureia/síntese química , Tioureia/química
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 71(2): 669-75, 2008 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-18337163

RESUMO

Some complexes of 2-phenylethyl dithiocarbamate, thiohydrazides and thiodiamines with dibenzyltin(IV) chloride, tribenzyltin(IV) chloride and di(para-chlorobenzyl)tin(IV) dichloride have been synthesized and investigated in 1:2 and 1:1 molar ratio. The dithiocarbamate ligand act as monoanionic bidentate and thiohydrazide, thiodiamines act as neutral bidentate ligand. The synthesized complexes have been characterized by elemental analysis and molecular weight determination studies and their bonding pattern suggested on the basis of electronic, infrared, 1H and 13C NMR spectroscopy. Using thermogravimetric (TG) and differential thermal analysis (DTA) various thermodynamic and kinetic parameters viz. reaction order (n), apparent activation energy (Ea), apparent activation entropy (S#) and heat of reaction (DeltaH) have been calculated and correlated with the structural aspects for solid-state decomposition of complexes. The ligands and their tin complexes have also been screened for their fungitoxicity activity against Rhizoctonia solanii and Sclerotium rolfsii and their ED50 values calculated.


Assuntos
Antifúngicos/química , Antifúngicos/farmacologia , Nitrogênio/química , Compostos Orgânicos de Estanho/química , Compostos Orgânicos de Estanho/farmacologia , Fenetilaminas/química , Enxofre/química , Cinética , Ligantes , Estrutura Molecular , Rhizoctonia/efeitos dos fármacos , Análise Espectral , Temperatura
4.
Eur J Med Chem ; 42(10): 1239-46, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17498848

RESUMO

Some new platinum (IV) and palladium (II) thiodiamine complexes of type [Pt(L)2Cl2] and [Pd(L)Cl2], [where, L=(cyclohexyl-N-thio)-1,2-ethylenediamine (L(1)) and (cyclohexyl-N-thio)-1,3-propanediamine (L(2))] have been synthesized. The thiodiamines coordinate as a bidentate N-S ligand. The synthesized platinum (IV) and palladium (II) complexes of the thiodiamines were characterized by elemental analysis, IR, mass, electronic and (1)H NMR spectroscopic studies. These complexes were also screened for cytotoxicity, in vitro antifungal and in vitro antibacterial activities. Thermodynamic parameters such as activation energy (Ea), apparent activation entropy (S(#)) and enthalpy change (DeltaH) for the dehydration and decomposition reactions of one complex has also been evaluated.


Assuntos
Aminas/síntese química , Aminas/toxicidade , Antibacterianos/síntese química , Antifúngicos/síntese química , Paládio/química , Compostos de Platina/síntese química , Compostos de Sulfidrila/química , Aminas/química , Antibacterianos/química , Antibacterianos/toxicidade , Antifúngicos/química , Antifúngicos/toxicidade , Aspergillus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Estrutura Molecular , Compostos de Platina/química , Compostos de Platina/toxicidade , Análise Espectral , Temperatura
5.
Spectrochim Acta A Mol Biomol Spectrosc ; 66(4-5): 1042-7, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16920010

RESUMO

Some platinum (IV) complexes [Pt(L)2Cl2] [where, L=2-aminopyridine-N-thiohydrazide (L1), (2-aminopyridine-N-thio)-1,3-propanediamine (L2), benzaldehyde-2-aminopyridine-N-thiohydrazone (L3) and salicylaldehyde-2-aminopyrtidine-N-thiohydrazone (L4)] have been synthesized. The thiohydrazides, thiodiamine and thiohydrazones can exist as thione-thiol tautomer and coordinate as a bidentate N-S ligand. The ligands found to act in monobasic bidentate fashion. Analytical data reveals that metal to ligand stoichiometry is 1:2. The complexes have been characterized by elemental analysis, IR, mass, electronic and 1H NMR spectroscopic studies. In vitro antibacterial and cytotoxic study have also been carried out for some complexes.


Assuntos
Antibacterianos/farmacologia , Diaminas/química , Hidrazinas/química , Hidrazonas/química , Compostos Organoplatínicos/química , Staphylococcus/efeitos dos fármacos , Antibacterianos/química , Morte Celular/efeitos dos fármacos , Diaminas/síntese química , Diaminas/farmacologia , Elétrons , Células HeLa , Humanos , Hidrazinas/síntese química , Hidrazinas/farmacologia , Hidrazonas/síntese química , Hidrazonas/farmacologia , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Compostos Organoplatínicos/síntese química , Compostos Organoplatínicos/farmacologia , Espectrofotometria Infravermelho
6.
Spectrochim Acta A Mol Biomol Spectrosc ; 65(3-4): 950-4, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16675295

RESUMO

Organotin(IV) complexes of tribenzyltin(IV) chloride and di(para-chlorobenzyl)tin(IV) dichloride with thiohydrazides have been reported. The ligands synthesized were bidentate coordinating through sulphur and terminal nitrogen atoms. These form 1:1 metal-ligand complexes. The following organotin(IV) complexes have been synthesized: (C(6)H(5)CH(2))(3)Sn(L(1))Cl, (p-ClC(6)H(4)CH(2))(2)Sn(L(1))Cl(2), (C(6)H(5)CH(2))(3)Sn(L(1))Cl, (p-ClC(6)H(4)CH(2))(2)Sn(L(2))Cl(2), (C(6)H(5)CH(2))(3)Sn(L(3))Cl, (p-ClC(6)H(4)CH(2))(2)Sn(L(3))Cl(2), where (L(1)): 2-phenylethyl N-thiohydrazide, (L(2)): N-(2-phenylethyl-N-thio)-1,3-propane diamine, (L(3)): N-(2-phenylethyl-N-thio)-1,2-ethane diamine. The complexes were synthesized by directly mixing, refluxing and stirring the ligands with organotin(IV) chlorides in a suitable solvent. The complexes were found to be pure and were characterized by elemental analysis, electronic, infrared, (1)H and (13)C NMR spectroscopy. These complexes were also studied for their thermal decomposition by thermogravimetry (TG) and differential thermal analysis (DTA). Various kinetic and thermodynamic parameters, viz. activation energy (E(a)), order of reaction (n), apparent activation entropy (S(#)) and heat of reaction (DeltaH) have been determined by using Horowitz-Metzger method. It was observed that these complexes are highly stable and the thermal degradation of these complexes is a spontaneous process. The ligands and their tin complexes have also been screened for their fungitoxicity activity and found to be quite active in this respect.


Assuntos
Diaminas/química , Hidrazinas/química , Compostos Orgânicos de Estanho/síntese química , Compostos de Enxofre/química , Diaminas/síntese química , Hidrazinas/síntese química , Ligantes , Compostos Orgânicos de Estanho/química , Análise Espectral , Compostos de Enxofre/síntese química
7.
Artigo em Inglês | MEDLINE | ID: mdl-16522376

RESUMO

A few Pt(IV) complexes of the type [Pt(L)(2)Cl(2)] [where L=morpholine dithiocarbamate (L(1)), aniline dithiocarbamate (L(2)), N-(methyl, cyclohexyl) dithiocarbamate (L(3)) and N-(ethyl, cyclohexyl) dithiocarbamate (L(4))] were synthesized. The complexes have been characterized by elemental analysis, molar conductance, IR, electronic, (1)H and (13)C NMR spectroscopic studies. The ligands found to act in monobasic bidentate fashion. Cyclicvoltammetric studies, antibacterial and in vitro antitumour studies were also carried out.


Assuntos
Compostos de Platina/química , Compostos de Platina/toxicidade , Tiocarbamatos/química , Tiocarbamatos/síntese química , Tiocarbamatos/toxicidade , Antibacterianos , Antineoplásicos , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Espectroscopia de Ressonância Magnética , Compostos de Platina/síntese química , Espectrofotometria Infravermelho
8.
Spectrochim Acta A Mol Biomol Spectrosc ; 61(13-14): 3097-101, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16165058

RESUMO

Some new organotin(IV) complexes with salicylaldehyde aniline-N-thiohydrazone (L1) and cinamaldehyde aniline-N-thiohydrazone (L2) of the type (p-ClC6H4)3Sn[L] Cl and (p-ClC6H4)2Sn[L]Cl2 have been synthesized (where L = L1 and L2). The complexes and ligands were characterized by elemental analysis and spectral (UV-vis, IR and 1H NMR) studies. In all the complexes, ligands act as bidentate, coordination through sulphur and azomethane nitrogen. Complexes are 1:1 metal ligands complexes. Antifungal studies of some complexes against Rhizoctonia bataticola fungal strain have been carried out.


Assuntos
Antifúngicos/síntese química , Antifúngicos/farmacologia , Hidrazonas/química , Compostos Orgânicos de Estanho/química , Compostos de Sulfidrila/química , Antifúngicos/química , Hidrazonas/síntese química , Hidrazonas/farmacologia , Estrutura Molecular , Rhizoctonia/efeitos dos fármacos , Espectrofotometria
9.
J Inorg Biochem ; 29(3): 181-6, 1987 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3572396

RESUMO

A number of organomercury(II) complexes involving isoniazid (I), of the type RHgCl(L)(II) [R = phenyl(C6H5), o-hydroxyphenyl (o-HOC6H4), p-hydroxyphenyl (p-HOC6H4), p-acetoxyphenyl (p-AcOC6H4), 2-furyl (2-C4H3O); L = isoniazid] have been synthesized and characterized. Conductance measurements indicate that the complexes are nonelectrolytes. From IR and UV studies, it is concluded that isoniazid acts as a bidentate ligand, coordinating through hydrazinic nitrogen and carbonyl oxygen. 1H and 13C NMR support the stoichiometry of the complexes. From fluoroscence studies a number of photochemical parameters have been elucidated. For the C6H5HgCl(L), p-HOC6H4HgCl(L), and p-AcOC6H4HgCl(L) complexes, thermogravimetric studies have been carried out and relevant kinetic and thermodynamic parameters for thermal degradation have been enumerated. In addition, the fragmentation pattern of the complexes has been analyzed on the basis of mass spectra. The C6H5HgCl(L) and p-HOC6H4HgCl(L) complexes have been screened for tuberculosis activity.


Assuntos
Isoniazida , Compostos Organomercúricos , Fenômenos Químicos , Química , Espectroscopia de Ressonância Magnética , Conformação Molecular , Espectrometria de Fluorescência , Espectrofotometria , Relação Estrutura-Atividade
10.
Talanta ; 21(7): 790-2, 1974 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18961534

RESUMO

The ring-oven method, combined with solvent extraction, has been used for the separation of all six platinum metals when present in mug-amounts in a drop of solution. The separated constituents are determined by ring-colorimetry.

11.
Talanta ; 18(10): 1061-4, 1971 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18960983

RESUMO

Potassium thiocarbonate reagent is proposed for the gravimetric determination of ruthenium(III), rhodium(III), palladium(II) and platinum(IV) in a highly acidic medium (pH 0.5-0.7) under suitable conditions. Ni, Zn, Mn(II), Al, Fe(III), Ti(IV), Zr, Th, Ca, Ba, Sr and Mg do not interfere. The largest relative error is 0.7% and the average error 0.2%.

12.
Talanta ; 16(3): 432-4, 1969 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18960519

RESUMO

Efficient analytical separations of Mo(VI), Tl(I), Se(IV), Te(IV) and V(V) from various ions have been made possible by using potassium thiocarbonate (PTC) as a complexing and precipitating agent. For gravimetric estimations, thermogravimetric studies of the products have been used to determine the optimum temperature range of ignition.

13.
Environ Pollut ; 44(1): 13-26, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-15092782

RESUMO

The effects of chronic exposure to fenvalerate, a synthetic pyrethroid insecticide, on the cladoceran Daphnia galeata mendotae were evaluated under laboratory conditions. The daphnids were exposed for their entire life cycle to concentrations ranging from 0.005 to 0.1 microg fenvalerate litre(-1). The parameters used to determined toxicity were survival, time to first reproduction, reproductive frequency, number of young per brood, cumulative brood size, intrinsic rate of natural increase (r(m)), generation time (T) and net reproductive rate (R(0)). A concentration of 0.005 microg fenvalerate litre(-1) resulted in an increase in longevity but a decrease in production of young. Higher concentrations caused a decrease in survival. Studies of shorter duration than the complete life cycle of the organisms would not have detected toxicity at such low levels. The intrinsic rate of natural increase, r(m), was not affected by fenvalerate until concentration reached 0.05 microg litre(-1) and r(m) decreased to 0.113 from 0.238. A concentration of 0.01 microg litre(-1) caused the net reproductive rate, R(0), and the generation time, T, to decrease to 73.2 offspring per female and 17.3 days from 125.9 offspring per female and 20.3 days, respectively.

14.
Environ Pollut ; 70(1): 35-55, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-15092145

RESUMO

This study evaluated the impact of concentrated pulse (16 microg litre(-1)) of the insecticide permethrin (emulsifiable concentrate) on the macroinvertebrate community of a northern Ontario headwater stream. Post-treatment drift increased by a factor of 2400 within minutes of the arrival of the insecticide. There was a significant (P<0.05) reduction in the abundance of invertebrates in most families as far as 260 m below the point of injection in both kick and artificial substrate samples. Greatest impact was observed in the mayflies, Baetis flavistriga. Heptagenia flavescens, and Epeorus sp., the stonefly, Leuctra tenuis, and the caddisfly, Dolophilodes distinctus. Diptera were not significantly reduced. The number of species occurring 100 m from the point of injection was reduced by 47%, but only by 17% at 260 m. There was no change in the per cent composition of functional feeding groups at any point after treatment. Recovery of most invertebrates was complete within 6 weeks of treatment.

15.
Environ Pollut ; 60(3-4): 291-304, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-15092382

RESUMO

To simulate runoff from agricultural lands, atrazine was applied to aquatic enclosures (112 m(3)) on 1 June 1983 at a concentration of 0.1 mg litre(-1). Thirty-five days later the nominal concentration was increased to 0.155 mg litre(-1). Treated enclosures became clearer with Secchi disc readings of 3.6 m compared to non-treated controls (2.9 m). Less than 5% of the first atrazine addition disappeared during the first 35 days and little effect on biological activity was observed. However, with the second enrichment the rate of loss of atrazine was rapid (t(1/2) = 150 days), ammonium, calcium, dissolved inorganic carbon and nitrate levels were higher, while oxygen, chlorophyll, dissolved organic carbon and particulate organic carbon concentrations were lower in the treated enclosures. These water quality changes cannot be explained by herbicide-water chemistry interactions alone, thereby suggesting an indirect effect as a consequence of atrazine inhibition on photosynthesis and possibly other microbial processes.

16.
Environ Pollut ; 46(2): 83-103, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-15092733

RESUMO

Chlorophyll a, freshweight biomass, ash-free dry weight, cell numbers, species richness, community carbon uptake and species-specific carbon uptake were used to monitor the impact of atrazine (2 chloro-4-ethylamino-6-isopropylamino-s-triazine) on an in situ, enclosed periphyton community. Atrazine concentrations ranging from 0.08 to 1.56 mg litre(-1) were used during the 2 years of study. In both 1982 and 1983, there was a shift from a chlorophyte- to a diatom-dominated community. In 1982 the cyanobacterium Cylindrospermum stagnale and the chlorophyte Tetraspora cylindrica developed isolated colonies in the 1.56 mg litre(-1) treatment, indicating resistance to atrazine at this concentration. After atrazine exposure, community productivity was reduced by 21% to 82% in the low to high exposures, respectively. After day 21 productivity returned to control levels. It was shown, using track autoradiography, that the productivities of the larger algae Mougeotia sp., Oedogonium sp., Tolypothrix limbata and Epithemia turgida were the most affected, with reductions of 74.3% to 93.1% that of the controls. All the biotic measures indicated reduced growth after herbicide exposure.

17.
Spectrochim Acta A Mol Biomol Spectrosc ; 60(13): 3087-92, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15477148

RESUMO

Triphenyl phosphine adducts of dithiocarbamate complexes of platinum(IV) and palladium(II) of the type [Pt(L)2PPh3Cl2] and [Pd(L)2PPh3] [L: morpholine dithiocarbamate (L1), aniline dithiocarbamate (L2) and N-(methyl, cyclohexyl) dithiocarbamate (L3)] were prepared and characterized by elemental analysis, electronic, IR, 1H NMR and 13C NMR spectral studies. Thermal studies of the complexes were carried out. In vitro antitumor activity has been screened towards human adenocarcinoma cell lines and showed significant inhibition even at very low concentration.


Assuntos
Paládio/química , Fosfinas/química , Platina/química , Compostos de Terfenil/química , Tiocarbamatos/química , Tiocarbamatos/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Ligantes , Análise Espectral , Temperatura
18.
Indian J Chest Dis Allied Sci ; 33(3): 119-28, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1794878

RESUMO

With a view to detect specific M. tuberculosis infection, mycobacterial proteins were purified initially by ammonium sulphate precipitation followed by ion-exchange chromatography. Out of the three fractions, namely P1, P2 and P3 precipitated with increasing concentrations (0-25%, 26-65% and 66-100% respectively) of ammonium sulphate, P2 fraction was found to be more immunoreactive. P2 fraction proteins were further fractionated into five fractions by salt gradient using DEAE-cellulose DE-52 ion-exchange chromatography. Immunoreactivity against tuberculous patients sera of all the fractions was assessed using ELISA test. The last fraction (DE-V) eluted with high salt concentration was found to have a more specific immunoreactive set of proteins within the range of 55 kD to 67 kD molecular weight. Multiple non-specific proteins were distributed in all the other fractions. ELISA test using P2 fraction proteins against tuberculous patients sera showed significantly higher (p less than 0.01) titre even in the absence of any other bacteriological evidence. DE-V fraction of P2 proteins was found to have a significantly high specificity for detecting M. tuberculosis infection in clinically confirmed and suspected tuberculous patients indicating its application in the diagnosis of the disease.


Assuntos
Antígenos de Bactérias/imunologia , Ensaio de Imunoadsorção Enzimática , Tuberculose Pulmonar/diagnóstico , Cromatografia por Troca Iônica , Humanos , Mycobacterium tuberculosis/imunologia
19.
J Assoc Physicians India ; 37(12): 777-9, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2699987

RESUMO

Real-time ultrasonography was done in 30 cases of non-visualised gallbladder on oral cholecystography. Surgico-pathological correlation revealed that a specific diagnosis indicating true pathology is possible preoperatively on ultrasonography.


Assuntos
Colecistite/diagnóstico , Colecistografia , Colelitíase/diagnóstico , Ultrassonografia , Adulto , Idoso , Feminino , Vesícula Biliar/patologia , Cálculos Biliares/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade
20.
J Assoc Physicians India ; 39(8): 604-5, 1991 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1814874

RESUMO

The role of real-time ultrasonography was evaluated in 50 randomly selected cases with a strong clinical suspicion of gallbladder diseases and normal oral cholecystogram. Of these, 13(26%) cases showed abnormalities on ultrasonography.


Assuntos
Doenças da Vesícula Biliar/diagnóstico por imagem , Adolescente , Adulto , Colecistografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ultrassonografia
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