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1.
Chemistry ; 24(41): 10498-10502, 2018 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-29740893

RESUMO

Room-temperature phosphorescence (RTP) was realized for the first time in a polyoxometalate-based charge-transfer (CT) hybrid material bearing polyoxometalates (POMs) as electron-donors (D) and rigid naphthalene diimides (NDIs) as electron-acceptors (A), meanwhile, this hybrid material displayed photochromism as well. The significant D-A anion-π interaction induced an additional through-space charge-transfer pathway. The resulting suitable D-A CT states can efficiently bridge the relatively large energy gap between the NDI-localized 1 π-π* and 3 π-π* states and thus trigger the ligand-localized phosphorescence (3 π-π*).

2.
Zhongguo Zhong Yao Za Zhi ; 43(3): 537-543, 2018 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-29600619

RESUMO

Eight limonoids were isolated from 95% ethanol extracts of neem(Azadirachta indica) seeds by various chromatographic methods. By comparison of their spectroscopic data with those reported in the literatures, these limonoids were determined as salannin(1), 1-detigloyl-1-isobutylsalannin(2), salannol-3-acetate(3), salannol(4), spirosendan(5), 1-detigloyloxy-3-deacetylsalannin-1-en-3-one(6), nimbin(7) and 6-deacetylnimbin(8). Compounds 2 and 5 were firstly isolated from this genus and 5 represented the only example of its type. And 6 is a new natural product. 6 showed inhibitory activity against HeLa and HL-60 cells, with IC50 of(21.61±4.37) and(27.33±5.74) µmol·L⁻¹, respectively. Both 7 and 8 mildly inhibited the growth of HeLa cells, with IC50 of (33.15±5.24) and (38.56±6.41) µmol·L⁻¹, respectively.


Assuntos
Azadirachta/química , Limoninas/farmacologia , Sementes/química , Células HL-60 , Células HeLa , Humanos , Limoninas/isolamento & purificação , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Extratos Vegetais
3.
Zhong Yao Cai ; 37(7): 1140-4, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25566645

RESUMO

OBJECTIVE: To investigate the constituents with antioxidant activities from alcalase hydrolysate of Arca subcrenata. METHODS: The consecutive chromatographic methods were employed,including ion-exchange chromatography, gel filtration chromatography, and reverse phase high-performance liquid chromatography (RP-HPLC). The amino acid sequences of the purified antioxidant peptides were determined by automated Edman degradation. RESULTS: Under the guidance of the assay of scavenging free radicals, two peptides with antioxidant activities, termed as A-Bg1 and A-Bh, were isolated and purified from the alcalase hydrolysate of Arca subcrenata. CONCLUSION: Constituents from the hydrolysate of Arca subcrenata might be a new potential resource of antioxidants.


Assuntos
Antioxidantes/isolamento & purificação , Peptídeos/isolamento & purificação , Sequência de Aminoácidos , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Cromatografia por Troca Iônica , Cromatografia de Fase Reversa , Subtilisinas
4.
Zhong Yao Cai ; 36(8): 1219-21, 2013 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-24558816

RESUMO

OBJECTIVE: To optimize the culture medium of transgenic Polygonium multiflorum hairy root and the effect of different elicitors on its growth. METHODS: Measured the growth curve of hairy root in four media, including MS, 1/2 MS, B5 and White and estimated the effects of elicitors on the hairy root biomass. RESULTS: MS medium was the most suitable of the four media for hairy root growth. The different concentrations of elicitors, salicylic acid and methyl jasmonate, inhibited the biomass accumulation of hairy root. CONCLUSION: MS is the optimum medium for transgenic Polygonium multiflorum hairy root. Two usual plant elicitors, salicylic acid and methyl jasmonate, can inhibit the growth of transgenic hairy root.


Assuntos
Raízes de Plantas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Acetatos , Meios de Cultura , Ciclopentanos , Oxilipinas , Ácido Salicílico
5.
Zhong Yao Cai ; 35(5): 800-3, 2012 May.
Artigo em Chinês | MEDLINE | ID: mdl-23213745

RESUMO

OBJECTIVE: To construct baicalin chitosan microparticles and compare the in vitro transdermal diffusion of baicalin in microparticles and cream. METHODS: Baicalin chitosan microparticles were constructed by using neutralization method and optimized by orthogonal test; The in vitro transdermal diffusion of baicalin in microparticles and cream was compared by using Franz cell. RESULTS: When the drug:stuff ratio was 1:3, concentration of chitosan was 2 mg/mL, mixed duration was 10 min, both the entrapment efficiency and drug loading efficiency of baicalin chitosan microparticles were over 60%; After 36 h, the cumulative release percentage of baicalin in microparticles and cream in vitro transdermal diffusion was 4.04% and 30%, respectively. The content of drug in microparticles and cream in the skin was 0.11% and 0.14%, respectively. And there was no significant difference (w = 7, P = 0.127) between the content of drug in microparticles and cream in the skin. CONCLUSION: The optimal procedure is simple and convenient with high entrapment efficiency and drug loading efficiency. The drug in the microparticles could be released slower and form local drug reservoir in the skin.


Assuntos
Quitosana/química , Sistemas de Liberação de Medicamentos/métodos , Flavonoides/administração & dosagem , Flavonoides/farmacocinética , Scutellaria baicalensis/química , Pele/metabolismo , Administração Cutânea , Animais , Quitosana/administração & dosagem , Composição de Medicamentos/métodos , Emulsões/administração & dosagem , Emulsões/química , Flavonoides/química , Camundongos , Microesferas , Tamanho da Partícula , Absorção Cutânea , Espectrofotometria Ultravioleta
6.
Zhong Yao Cai ; 35(6): 869-72, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23236817

RESUMO

OBJECTIVE: To investigate the effect of artermisinic acid on the secondary metabolites production of Panax quinquefolium crown galls. METHODS: Artemisinic acid was added into the suspended cells of Panax quinquefolium crown galls and co-culture for two days. Products were isolated with chromatographic method. RESULTS: Three hydroxyl octadecenoic acids [9,12,13-trihydroxy-10-octadecenoic acid (1), 11,12,13-trihydroxy-9-octadecenoic acid (2) and 11-hydroxy-12,13-epoxy-9-octadecenoic acid (3)] were isolated from crown galls of Panax quinquefolium. CONCLUSION: Artermisinic acid as one of the new type of phytohormones that might induce the production of 13-lipoxygenases in crown galls of Panax quinquefolium.


Assuntos
Artemisininas/farmacologia , Ácidos Graxos/biossíntese , Panax/metabolismo , Plantas Medicinais/metabolismo , Células Cultivadas , Cromatografia Líquida de Alta Pressão/métodos , Meios de Cultura , Ácidos Graxos/química , Ácidos Graxos/isolamento & purificação , Hidroxiácidos/química , Hidroxiácidos/isolamento & purificação , Ácidos Oleicos/biossíntese , Ácidos Oleicos/química , Ácidos Oleicos/isolamento & purificação , Panax/efeitos dos fármacos , Panax/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas , Plantas Medicinais/efeitos dos fármacos , Plantas Medicinais/crescimento & desenvolvimento , Técnicas de Cultura de Tecidos/métodos
7.
Dalton Trans ; 41(38): 11783-7, 2012 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-22903202

RESUMO

Two polyoxometalate-pillared 3D compounds, {Cu(5)(2-ptz)(6)(H(2)O)(4)(SiW(12)O(40))}·4H(2)O 1 and {Cu(9)(2-ptz)(12)(H(2)O)(6)(PMo(12)O(40))(2)}·H(2)O 2 (2-ptz = 5-(2-pyridyl)tetrazole) have been constructed based on different polyoxometalate anions, and copper-organic coordination polymer sheets by a hydrothermal method. Magnetic investigations reveal that both 1 and 2 exhibit antiferromagnetic coupling between the Cu(II) ions. Structural studies show the compound 1 exhibits a typical pcu-type net with the Schälfli symbol of {4(12)·6(3)}, and that compound 2 is a (3,4,6)-connected framework with novel {4(4)·6(10)·10}{6(3)}(2){6(5)·8} topology which has not been reported to date.

8.
Zhong Yao Cai ; 34(6): 901-4, 2011 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-22017006

RESUMO

OBJECTIVE: To synthesis 4-methyl-7-allyloxy coumarin by Williamson etherification from 4-methyl-7-hydroxy coumarin and apply as a substrate in hairy roots of Polygonum multiflorum. METHODS: The synthesis reaction of 4-methyl-7-allyloxy coumarin used the allyl bromide and potassium carbonate as catalysts, and acetone as solvent reacted for 17 hours, then the product was isolated. 4-methyl-7-allyloxy coumarin was added into the media of supension transgenic hairy roots of Polygonum multiflorum which had been precultured for 8 d, and then co-cultured for another 7 d. The biotransformation products were detected by TLC and HPLC and isolated by various chromatographic methods. RESULTS: Two biotransformation products, 4-methyl-7-hydroxy coumarin and 4-methyl-coumarin-7-O-beta-D-glucoside were isolated and identified. CONCLUSION: Hairy roots of Polygonum multiflorum contains not only glycosyltransferase but also hydrolysis enzymes.


Assuntos
Himecromona/análogos & derivados , Himecromona/metabolismo , Raízes de Plantas/metabolismo , Polygonum/metabolismo , Biotransformação , Cromatografia Líquida de Alta Pressão , Técnicas de Cocultura/métodos , Glucosídeos/metabolismo , Raízes de Plantas/genética , Plantas Geneticamente Modificadas , Polygonum/genética
9.
Inorg Chem ; 50(22): 11403-11, 2011 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-22017386

RESUMO

Two new complexes [Cu(I)(3)(L1)I(3)](n) (1, L1 = 2,5-bis(4-pyridyl)-1,3,4-oxadiazole) and [Cu(I)(3)(L2)I(2)](n) (2, L2 = 2,5-bis(4-pyridyl)-1,2,4-triazolate) are controllably formed by using aqueous ammonia to regulate the pH value of the reaction involving CuI and L1. Interestingly, L2 of 2 is in situ generated from the ring transform of L1 when increase the pH value of the reaction. 1 exhibits 2-D layer, while 2 shows 3-D MOFs with a novel 3-nodal 4,4,5-connected net topology of an unprecedented Point (Schlafli) symbol: (4·5(2)·6(2)·7)(5(4)·8(2))(4(3)·5·6(6)). Although both 1 and 2 are built of CuI and similar ligands, different arrangements of CuI chains and ligands endow them with different physical properties. 1 displays a strong pure red luminescence emission, while 2 is nonluminescent and shows a broad absorption band covering the whole UV-vis-NIR spectrum range. The emissive excited states of 1 and the charge transitions of the optical absorption for 2 are solved by DFT calculations.

10.
J Agric Food Chem ; 59(21): 11548-52, 2011 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-21973186

RESUMO

A novel polysaccharide (LCP50S-2) with antioxidant activity was isolated from Litchi chinensis Sonn. The structure of LCP50S-2 was elucidated on the basis of physicochemical and instrumental analyses, and its average molecular weight was determined by gel permeation chromatography to be 2.19 × 10(2) kDa. The backbone of LCP50S-2 was composed of (1→3)-linked ß-L-rhamnopyranosyl residues, (1→4)-linked α-D-xylopyranosyl residues, (1→4)-linked ß-D-glucopyranosyl residues, and (1→4)-linked α-D-glucopyranosyl residues which branched at O-6. The two branches consisted of α-L-arabinopyranosyl residues and (1→6)-linked ß-D-galactopyranosyl residues terminated with α-L-arabinopyranosyl residues, respectively. In the in vitro antioxidant assay, LCP50S-2 was found to possess DPPH radical-scavenging activity and hydroxyl radical-scavenging activity with IC(50) values of 220 and 266 µg/mL, respectively.


Assuntos
Antioxidantes/química , Litchi/química , Extratos Vegetais/química , Polissacarídeos/química , Antioxidantes/isolamento & purificação , Sequência de Carboidratos , Dados de Sequência Molecular , Estrutura Molecular , Extratos Vegetais/isolamento & purificação , Polissacarídeos/isolamento & purificação
11.
Zhong Yao Cai ; 34(12): 1950-3, 2011 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-22500437

RESUMO

OBJECTIVE: To isolate and identify the polysaccharides of Ginkgo biloba and determine their antioxidant activities in vitro. METHODS: Used hot extraction and alcohol precipitation to get the crude polysaccharides, removed protein with Sevag method, further purify by column chromatography packed with DEAE-52 and DEAE-Sepharose Fast Flow. The homogeneity and molecular weights were evaluated, configuration and monosaccharide composition were measured by IR and high performance ion chromatography analysis, the scavenging activities of GBPB-S on hydroxyl radical and DPPH were measured. RESULTS: The molecular weights of GBPB-W and GBPB-S were 26 300 and 19 100, and both of them were composed of rhamnose, arabinose, galactose, glucose and mannose with the ratios of (3.48: 8.47:3.73: 1.76: 1) and (5.34: 5.37: 5.27: 1:1.68). GBPB-S had certain scavenging effect on hydroxyl radical and DPPH. CONCLUSION: The polysaccharide isolated from Ginkgo biloba has a direct antioxidant activities in vitro.


Assuntos
Depuradores de Radicais Livres/farmacologia , Ginkgo biloba/química , Polissacarídeos/isolamento & purificação , Polissacarídeos/farmacologia , Tecnologia Farmacêutica/métodos , Compostos de Bifenilo/metabolismo , Depuradores de Radicais Livres/química , Depuradores de Radicais Livres/isolamento & purificação , Radical Hidroxila/metabolismo , Peso Molecular , Monossacarídeos/química , Picratos/metabolismo , Folhas de Planta/química , Caules de Planta/química , Polissacarídeos/química , Análise Espectral/métodos
12.
Zhong Yao Cai ; 33(7): 1048-51, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21133060

RESUMO

OBJECTIVE: To analysis and compare the taxol content in different parts of Taxus madia and Taxus chinensis var. mairei by High Performance Liquid Chromatography (HPLC). METHODS: 85% EtOH and CH2Cl2 were used for the extraction of taxol. By HPLC, the methodology study and taxol content investigation were performed. RESULTS: The taxol was extracted successfully. One simple and reliable methodology was built up. Basing on these, the taxol content in these two Taxus spp. were analysed and compared, among of which the leaf of Taxus chinensis var. mairei has the highest taxol content (5.18 x 10(-5), w/w). CONCLUSION: Taxol and its content in the original plants can be simply and reliably extracted and investigated by these methods, which also can provided the scientific basis for the rational development of Taxus spp.


Assuntos
Antineoplásicos Fitogênicos/análise , Paclitaxel/análise , Folhas de Planta/química , Taxus/química , Antineoplásicos Fitogênicos/isolamento & purificação , Cromatografia Líquida de Alta Pressão/métodos , Conservação dos Recursos Naturais , Etanol/química , Paclitaxel/isolamento & purificação , Casca de Planta/química , Reprodutibilidade dos Testes , Taxus/classificação , Taxus/crescimento & desenvolvimento , Tecnologia Farmacêutica/métodos , Árvores/química , Árvores/crescimento & desenvolvimento
13.
Zhong Yao Cai ; 33(5): 662-5, 2010 May.
Artigo em Chinês | MEDLINE | ID: mdl-20873547

RESUMO

OBJECTIVE: To investigate the biotransformation of artemisinic acid by cell suspension cultures of Cephalotaxus fortunei and Artemisia annua. METHODS: Artemisinic acid was added into to the media of the suspension cells of Cephalotaxus fortunei and Artemisia annua in their logarithmic growth phase. The biotransfromed product was detected with HPLC and isolated by silica gel column, Sephadex LH20 and ODS chromatography methods. The chemical structure of biotransformed product was elucidated on the basis of physical-chemical properties and spectroscopic data. Otherwise, the influence of co-cultured time on conversion ratio was investigated with HPLC. RESULTS: One biotransformed product, 3-alpha-hydroxyartemisinic acid, was obtained after two days of artemisinic acid administration to the suspension cells of Cephalotaxus fortunei and Artemisia annua. The optimal co-cultured time in suspension cells of Cephalotaxus fortunei was 2 days with the highest biotransformation rate of 8.42%, and in the case of Artemisia annua, it was 3 days and 3.95% respectively. CONCLUSION: It was the first time for the biotransformation of artemisinic acid to 3-alpha-hydroxyartemisinic acid by using cell suspension cultures of Cephalotaxus fortunei and Artemisia annua.


Assuntos
Artemisia annua/metabolismo , Artemisininas/metabolismo , Cephalotaxus/metabolismo , Artemisia annua/química , Artemisia annua/citologia , Artemisininas/química , Artemisininas/isolamento & purificação , Biotransformação , Células Cultivadas , Cephalotaxus/química , Cephalotaxus/citologia , Cromatografia Líquida de Alta Pressão , Meios de Cultura , Estrutura Molecular
15.
Zhong Yao Cai ; 33(2): 180-3, 2010 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-20575407

RESUMO

OBJECTIVE: Chondroitin Sulfate (CS) from different animals were extracted, which antihypertensive activities were compared. METHODS: CS from the bovine and chicken cartilages were extracted by diluted alkali-enzyme hydrolysis method, with removed free protein by Sevag method, separated and purified by quaternary ammonium complex. Their antihypertensive activities were tested by the modal of SPF rat. RESULTS: The extracted CS didn't have peptide, amino acid or other acid mucopolysaccharides determined by electrophoresis and chromatography, the results of IR was consisted with that of chondroitin sulfate supplied by Sigma Both BCCS and CCCS indicated the antihypertensive activities in the low dosage. Besides, BCCS had faster efficacy but shorter duration than that of CCCS. CONCLUSION: Both BCCS and CCCS had high purity. Animal experiments showed that BCCS and CCCS have the effect of the antihypertensive, which activity of CCCS was more significant than that of BCCS.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Cartilagem/química , Sulfatos de Condroitina/isolamento & purificação , Sulfatos de Condroitina/farmacologia , Animais , Anti-Hipertensivos/isolamento & purificação , Anti-Hipertensivos/farmacologia , Cartilagem/metabolismo , Bovinos , Galinhas , Sulfatos de Condroitina/química , Feminino , Masculino , Camundongos , Costelas , Escápula , Tecnologia Farmacêutica/métodos
16.
Chem Commun (Camb) ; 46(9): 1449-51, 2010 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-20162144

RESUMO

Presented here is a homochiral three-dimensional diamondoid framework material, [Zn(AMTD)(2)](n) generated through an unusual spontaneous asymmetrical crystallization from achiral precursors without any enantiopure additives, which first demonstrates that symmetry breaking could be driven by the cooperation of twisted framework topology and an asymmetrical ligand.

17.
Fitoterapia ; 81(5): 339-42, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19836436

RESUMO

A new ceramide and a new poly-hydroxyl octadecenoic acid were isolated from transgenic crown galls of Panax quinquefolium. Their structures were elucidated as (2S, 3S, 4R, 20E)-2-[(2'R)-2'-hydroxyl-palmitoyl-amino]-20-hexacosene-1, 3, 4-triol (1) and 12, 13, 15-trihydroxy-9-octadecenoic acid (2) respectively on the basis of spectroscopic and chemical methods.


Assuntos
Ceramidas/isolamento & purificação , Hidroxiácidos/isolamento & purificação , Ácidos Oleicos/isolamento & purificação , Panax/química , Extratos Vegetais/química , Plantas Geneticamente Modificadas/química , Agrobacterium tumefaciens/genética , Ceramidas/química , Hidroxiácidos/química , Estrutura Molecular , Ácidos Oleicos/química , Panax/genética , Panax/microbiologia , Extratos Vegetais/isolamento & purificação , Tumores de Planta/microbiologia , Plantas Geneticamente Modificadas/microbiologia
18.
Zhong Yao Cai ; 32(9): 1339-42, 2009 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-20034207

RESUMO

OBJECTIVE: To optimize the culture conditions and determine the content of polysaccharides in crown gall of Panax quinquefolium. METHODS: The orthogonal design was used for the optimization of culture condition (such as media, inoculum amount, pH and the content of inorganic elements in media) and their effects on the polysaccharides content. RESULTS: (1) The crown gall tissue could grow and produce polysaccharides in MS (Murashige & Skoog) solid medium without any hormones; (2) The time-dependent regularity of the growth amount and polysaccharides content of the crown gall tissue in MS solid medium was approached: polysaccharides content was the highest in 21 d and biomass achieved to the greatest in 24 d; (3) The polysaccharides content and growth amount were the highest when pH 5.6 of media; (4) The inoculation of 4 - 7 g (FW/flask) was comparatively advantage to the growth of the crown gall, but no effect on polysaccharides content. CONCLUSION: This method can be used to accumulate the high contents of polysaccharides in crown gall cultures of P. quinquefolium.


Assuntos
Panax/crescimento & desenvolvimento , Plantas Medicinais/crescimento & desenvolvimento , Polissacarídeos/metabolismo , Técnicas de Cultura de Tecidos/métodos , Meios de Cultura , Concentração de Íons de Hidrogênio , Panax/genética , Panax/metabolismo , Plantas Geneticamente Modificadas , Plantas Medicinais/genética , Plantas Medicinais/metabolismo , Fatores de Tempo
19.
Zhong Yao Cai ; 32(5): 670-3, 2009 May.
Artigo em Chinês | MEDLINE | ID: mdl-19771838

RESUMO

OBJECTIVE: To provide theoretical basis for the production of ginsenosides by using modern biotechnologies, the comparative studies of the amount of ginsenosides between the crown galls and Chinese medicinal materials of Panax quinquefolium were carried out. METHODS: Total ginsenosides were determined by spectrophotometry, and the contents of ginsenoside Rb1, Rb3, Rc, Re were determined by HPLC. RESULTS: (1) The total ginsenosides in the crown galls of Panax quinquefolium (aftert 27 days' cultivation) was almost as much as that of Chinese medicinal material of Panax quinquefolium. (2) The contents of ginsenoside Rb1, Re in the crown galls were about half of that in Chinese medicinal materials of Panax quinquefolium, and ginsenoside Rc was about 80%. But the amount of ginsenoside Rb3 in the crown galls of Panax quinquefolium was much more than that in Chinese medicinal materials of Panax quinquefolium as almost 15 times higher. CONCLUSION: The crown galls of Panax quinquefolium may be a new potential resource for large-scale production of ginsenosides.


Assuntos
Ginsenosídeos/biossíntese , Panax/metabolismo , Plantas Medicinais/metabolismo , Cromatografia Líquida de Alta Pressão , Ginsenosídeos/isolamento & purificação , Farmacognosia , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas , Controle de Qualidade , Reprodutibilidade dos Testes , Técnicas de Cultura de Tecidos/métodos
20.
Inorg Chem ; 48(16): 7691-7, 2009 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-19591440

RESUMO

Three novel microporous three-dimensional (3-D) metal-organic framework materials [ML](n) [M = Ni, Co, Cd; L = N,N'-bis(4-picolinoyl)hydrazine] were obtained from hydrothermal reactions. The organic ligand L was formed through the in situ ring-opening hydrolysis reaction of 2,5-bis(4-pyridyl)-1,3,4-oxadiazole with the assistance of metal ions. Single-crystal X-ray diffraction studies reveal that complexes 1-3 adopt 6-connected 3-D networks of distorted alpha-Po topology, which are built from non-interpenetrated (4,4) grids cross-linked by zigzag chains. These isomorphic complexes are all of high thermal stability, but some other physical properties are quite different because of their different metal centers. Antiferromagnetic exchange was observed between Ni(II) centers of complex 1, while ferromagnetic for Co(II) centers of complex 2. Complex 3 exhibits strong fluorescence emission.

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