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1.
J Nanobiotechnology ; 22(1): 324, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38858692

RESUMO

Breast cancer remains a malignancy that poses a serious threat to human health worldwide. Chemotherapy is one of the most widely effective cancer treatments in clinical practice, but it has some drawbacks such as poor targeting, high toxicity, numerous side effects, and susceptibility to drug resistance. For auto-amplified tumor therapy, a nanoparticle designated GDTF is prepared by wrapping gambogic acid (GA)-loaded dendritic porous silica nanoparticles (DPSNs) with a tannic acid (TA)-Fe(III) coating layer. GDTF possesses the properties of near-infrared (NIR)-enhanced and pH/glutathione (GSH) dual-responsive drug release, photothermal conversion, GSH depletion and hydroxyl radical (·OH) production. When GDTF is exposed to NIR laser irradiation, it can effectively inhibit cell proliferation and tumor growth both in vitro and in vivo with limited toxicity. This may be due to the synergistic effect of enhanced tumor accumulation, and elevated reactive oxygen species (ROS) production, GSH depletion, and TrxR activity reduction. This study highlights the enormous potential of auto-amplified tumor therapy.


Assuntos
Neoplasias da Mama , Glutationa , Nanopartículas , Espécies Reativas de Oxigênio , Dióxido de Silício , Neoplasias da Mama/tratamento farmacológico , Feminino , Nanopartículas/química , Animais , Glutationa/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Camundongos , Dióxido de Silício/química , Espécies Reativas de Oxigênio/metabolismo , Linhagem Celular Tumoral , Xantonas/química , Xantonas/farmacologia , Taninos/química , Taninos/farmacologia , Proliferação de Células/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Liberação Controlada de Fármacos , Antineoplásicos/farmacologia , Antineoplásicos/química
2.
Theranostics ; 13(15): 5322-5347, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37908727

RESUMO

Cancer is still one of the major problems threatening human health and the therapeutical efficacies of available treatment choices are often rather low. Due to their favorable biocompatibility, simplicity of modification, and improved therapeutic efficacy, peptide-based self-assembled delivery systems have undergone significant evolution. Physical encapsulation and covalent conjugation are two common approaches to load drugs for peptide assembly-based delivery, which are always associated with drug leaks in the blood circulation system or changed pharmacological activities, respectively. To overcome these difficulties, a more elegant peptide-based assembly strategy is desired. Notably, peptide-mediated co-assembly with drug molecules provides a new method for constructing nanomaterials with improved versatility and structural stability. The co-assembly strategy can be used to design various nanostructures for cancer therapy, such as nanotubes, nanofibrils, hydrogels, and nanovesicles. Recently, these co-assembled nanostructures have gained tremendous attention for their unique superiorities in tumor therapy. This article describes the classification of assembled peptides, driving forces for co-assembly, and specifically, the design methodologies for various drug molecules in co-assembly. It also highlights recent research on peptide-mediated co-assembled delivery systems for cancer therapy. Finally, it summarizes the pros and cons of co-assembly in cancer therapy and offers some suggestions for conquering the challenges in this field.


Assuntos
Nanoestruturas , Nanotubos , Neoplasias , Humanos , Peptídeos/química , Nanoestruturas/química , Hidrogéis/química , Neoplasias/tratamento farmacológico , Sistemas de Liberação de Medicamentos/métodos
3.
Artigo em Inglês | MEDLINE | ID: mdl-37861012

RESUMO

BACKGROUND: Although quercetin exhibits promising anti-tumor properties, its clinical application is limited due to inherent defects and a lack of tumor targeting. OBJECTIVE: This study aimed to prepare and characterize active targeting folate-chitosan modified quercetin liposomes (FA-CS-QUE-Lip), and its antitumor activity in vitro and in vivo was also studied. METHODS: Box-Behnken Design (BBD) response surface method was used to select the optimal formulation of quercetin liposomes (QUE-LP). On this basis, FA-CS-QUE-LP was obtained by connecting folic acid chitosan complex (FA-CS) and QUE-LP. The release characteristics in vitro of QUE-LP and FA-CS-QUE-LP were studied. Its inhibitory effects on HepG2 cells were studied by the MTT method. The pharmacokinetics and pharmacodynamics in vivo were studied in healthy Wistar mice and S180 tumor-bearing mice, respectively. RESULTS: The average particle size, zeta potential and encapsulation efficiency of FA-CS-QUELP were 261.6±8.5 nm, 22.3±1.7 mV, and 98.63±1.28 %, respectively. FA-CS-QUE-LP had a sustained release effect and conformed to the Maloid-Banakar release model (R2=0.9967). The results showed that FA-CS-QUE-LP had higher inhibition rates on HepG2 cells than QUE-Sol (P<0.01). There was a significant difference in AUC, t1/2, CL and other pharmacokinetic parameters among QUE-LP, FA-CS-QUE-LP, and QUE-Sol (P<0.05). In in vivo antitumor activity study, the weight inhibition rate and volume inhibition rate of FA-CS-QUE-LP were 30.26% and 37.35%, respectively. CONCLUSION: FA-CS-QUE-LP exhibited a significant inhibitory effect on HepG2 cells, influenced the pharmacokinetics of quercetin in mice, and demonstrated a certain inhibitory effect on S180 tumor-bearing mice, thus offering novel avenues for cancer treatment.

4.
Int J Pharm ; 642: 123044, 2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37178790

RESUMO

Dysregulation of microRNAs (miRNAs) expression is closely related to cancers and managing miRNA expression holds great promise for cancer therapy. However, their wide clinical application has been hampered by their poor stability, short half-life and non-specific biodistribution in vivo. Herein, a novel biomimetic platform designated as RHAuNCs-miRNA for improved miRNA delivery was prepared through wrapping miRNA-loaded functionalized Au nanocages (AuNCs) with red blood cell (RBC) membrane. RHAuNCs-miRNA not only successfully loaded miRNAs but also effectively protected them from enzymatic degradation. With good stability, RHAuNCs-miRNA had the characteristics of photothermal conversion and sustained release. Cellular uptake of RHAuNCs-miRNA by SMMC-7721 cells was in a time-dependent manner via clathrin- and caveolin-mediated endocytosis. The uptake of RHAuNCs-miRNAs was affected by cell types and improved by mild near infrared (NIR) laser irradiation. More importantly, RHAuNCs-miRNA exhibited a prolonged circulation time without the occurrence of accelerated blood clearance (ABC) in vivo, resulting in efficient delivery to tumor tissues. This study may demonstrate the great potential of RHAuNCs-miRNA for improved miRNAs delivery.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroRNAs , Humanos , Carcinoma Hepatocelular/terapia , Fototerapia/métodos , Neoplasias Hepáticas/tratamento farmacológico , Biomimética , Distribuição Tecidual , Eritrócitos
5.
J Biomater Appl ; 37(10): 1847-1857, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37102311

RESUMO

Due to the heterogeneity and the complexity of the tumor microenvironment, combination therapy, especially the combination of chemotherapy and photothermal therapy (PTT), had received increasing attention. However, the co-delivery of small molecule drugs for chemotherapy and photothermal agents was a key issue. Herein, we prepared a novel thermo-sensitive hydrogel loading with elemene (ELE)-loaded and nano graphene oxide (NGO)-based liposomes for enhanced combined therapy. ELE was applied as the model drug for chemotherapy because it was a natural sesquiterpene drug with broad-spectrum and efficient antitumor activity. NGO was applied as drug carrier and photothermal agent simultaneously due to its two-dimensional structure and high photo-thermal conversion efficacy. NGO was further modified with glycyrrhetinic acid (GA) to improve its water dispersion, biocompatibility and tumor-targeting ability. ELE was loaded by GA-modified NGO (GA/NGO) to prepare the liposomes designated as ELE-GA/NGO-Lip, which was further mixed with chitosan (CS) solution and ß-glycerin sodium phosphate (ß-GP) solution to prepare the thermo-sensitive hydrogel designated as ELE-GA/NGO-Lip-gel. The obtained ELE-GA/NGO-Lip-gel had the gelling temperature of 37°C, temperature and pH-response gel dissolution and high photo-thermal conversion effect. More importantly, ELE-GA/NGO-Lip-gel upon 808 nm laser irradiation had relative high anti-tumor efficiency against SMMC-7721 cells in vitro. This research might provide a potent platform for the application of thermos-sensitive injectable hydrogel in combined tumor therapy.


Assuntos
Neoplasias , Sesquiterpenos , Humanos , Lipossomos/química , Hidrogéis/química , Portadores de Fármacos/química , Sesquiterpenos/farmacologia , Linhagem Celular Tumoral , Microambiente Tumoral
6.
J Ethnopharmacol ; 301: 115763, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36183949

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Acute lung injury (ALI) is one of the fatal complications of respiratory virus infections such as influenza virus and coronavirus, which has high clinical morbidity and mortality. Jinhua Qinggan granules (JHQG) has been approved by China Food and Drug Administration in the treatment of H1N1 influenza and mild or moderate novel coronavirus disease 2019 (COVID-19), which is an herbal formula developed based on Maxingshigan decoction and Yinqiao powder that have been used to respiratory diseases in China for thousands of years. However, the underlying mechanism of JHQG in treating infectious diseases remains unclear. AIM OF THE STUDY: This study investigated the effects of JHQG on neutrophil apoptosis and key signaling pathways in lipopolysaccharide (LPS) -induced ALI mice in order to explore its mechanism of anti-inflammation. MATERIALS AND METHODS: The effect of JHQG on survival rate was observed in septic mouse model by intraperitoneal injection of LPS (20 mg/kg). To better pharmacological evaluation, the mice received an intratracheal injection of 5 mg/kg LPS. Lung histopathological changes, wet-to-dry ratio of the lungs, and MPO activity in the lungs and total protein concentration, total cells number, TNF-α, IL-1ß, IL-6, and MIP-2 levels in BALF were assessed. Neutrophil apoptosis rate was detected by Ly6G-APC/Annexin V-FITC staining. Key proteins associated with apoptosis including caspase 3/7 activity, Bcl-xL and Mcl-1 were measured by flow cytometry and confocal microscope, respectively. TLR4 receptor and its downstream signaling were analyzed by Western blot assay and immunofluorescence, respectively. RESULTS: JHQG treatment at either 6 or 12 g/kg/day resulted in 20% increase of survival in 20 mg/kg LPS-induced mice. In the model of 5 mg/kg LPS-induced mice, JHQG obviously decreased the total protein concentration in BALF, wet-to-dry ratio of the lungs, and lung histological damage. It also attenuated the MPO activity and the proportion of Ly6G staining positive neutrophils in the lungs, as well as the MIP-2 levels in BALF were reduced. JHQG inhibited the expression of Mcl-1 and Bcl-xL and enhanced caspase-3/7 activity, indicating that JHQG partially acted in promoting neutrophil apoptosis via intrinsic mitochondrial apoptotic pathway. The levels of TNF-α, IL-1ß, and IL-6 were significantly declined in LPS-induced mice treated with JHQG. Furthermore, JHQG reduced the protein expression of TLR4, MyD88, p-p65 and the proportion of nuclei p65, suggesting that JHQG treatment inhibited TLR4/MyD88/NF-κB pathway. CONCLUSION: JHQG reduced pulmonary inflammation and protected mice from LPS-induced ALI by promoting neutrophil apoptosis and inhibition of TLR4/MyD88/NF-κB pathway, suggesting that JHQG may be a promising drug for treatment of ALI.


Assuntos
Lesão Pulmonar Aguda , COVID-19 , Vírus da Influenza A Subtipo H1N1 , Camundongos , Animais , NF-kappa B/metabolismo , Receptor 4 Toll-Like/metabolismo , Lipopolissacarídeos/toxicidade , Fator 88 de Diferenciação Mieloide/metabolismo , Neutrófilos , Fator de Necrose Tumoral alfa/metabolismo , Vírus da Influenza A Subtipo H1N1/metabolismo , Interleucina-6/metabolismo , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Proteína de Sequência 1 de Leucemia de Células Mieloides/uso terapêutico , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/tratamento farmacológico , Lesão Pulmonar Aguda/metabolismo , Apoptose
7.
J Biomater Appl ; 37(1): 151-165, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35343281

RESUMO

Malignant tumor is one of the major diseases with high morbidity and mortality. The purpose of this study is to prepare berberine hydrochloride (BH) in situ thermo-sensitive hydrogel based on glycyrrhetinic acid (GA) modified nano graphene oxide (NGO) (GA-BH-NGO-gel). NGO was taken as the photosensitizer, GA was taken as the target molecule, and BH was taken as the model drug. The physicochemical properties and anti-tumor activity in vivo and in vitro were also studied. This subject could provide a certain theoretical basis for the chemo-photothermal therapy combined treatment of malignant tumor. The release behavior of GA-BH-NGO-gel in vitro presented sustained and temperature-dependent drug release effect. The anti-tumor activity studies in vivo and in vitro had shown that GA-BH-NGO-gel had stronger anti-tumor activity, which could be targeting distributed to the tumor tissues. Moreover, the inhibitory effect of GA-BH-NGO-gel was enhanced when combined with 808 nm of laser irradiation. In this research, the chemo-photothermal combination therapy was applied into the tumor treatment, which may provide certain research ideas for the clinical treatment of malignant tumor.


Assuntos
Carcinoma Hepatocelular , Ácido Glicirretínico , Grafite , Neoplasias Hepáticas , Carcinoma Hepatocelular/tratamento farmacológico , Linhagem Celular Tumoral , Doxorrubicina , Grafite/química , Humanos , Hidrogéis , Neoplasias Hepáticas/tratamento farmacológico , Óxidos/química , Terapia Fototérmica
8.
Oxid Med Cell Longev ; 2020: 3153082, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32215172

RESUMO

Diosgenin (DG), a well-known steroidal sapogenin, is present abundantly in medicinal herbs such as Dioscorea rhizome, Dioscorea villosa, Trigonella foenum-graecum, Smilax China, and Rhizoma polgonati. DG is utilized as a major starting material for the production of steroidal drugs in the pharmaceutical industry. Due to its wide range of pharmacological activities and medicinal properties, it has been used in the treatment of cancers, hyperlipidemia, inflammation, and infections. Numerous studies have reported that DG is useful in the prevention and treatment of neurological diseases. Its therapeutic mechanisms are based on the mediation of different signaling pathways, and targeting these pathways might lead to the development of effective therapeutic agents for neurological diseases. The present review mainly summarizes recent progress using DG and its derivatives as therapeutic agents for multiple neurological disorders along with their various mechanisms in the central nervous system. In particular, those related to therapeutic efficacy for Parkinson's disease, Alzheimer's disease, brain injury, neuroinflammation, and ischemia are discussed. This review article also critically evaluates existing limitations associated with the solubility and bioavailability of DG and discusses imperatives for translational clinical research. It briefly recapitulates recent advances in structural modification and novel formulations to increase the therapeutic efficacy and brain levels of DG. In the present review, databases of PubMed, Web of Science, and Scopus were used for studies of DG and its derivatives in the treatment of central nervous system diseases published in English until December 10, 2019. Three independent researchers examined articles for eligibility. A total of 150 articles were screened from the above scientific literature databases. Finally, a total of 46 articles were extracted and included in this review. Keywords related to glioma, ischemia, memory, aging, cognitive impairment, Alzheimer, Parkinson, and neurodegenerative disorders were searched in the databases based on DG and its derivatives.


Assuntos
Diosgenina/análogos & derivados , Diosgenina/uso terapêutico , Doenças do Sistema Nervoso/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Animais , Disponibilidade Biológica , Cognição/efeitos dos fármacos , Diosgenina/farmacocinética , Diosgenina/farmacologia , Modelos Animais de Doenças , Humanos , Estrutura Molecular , Fármacos Neuroprotetores/farmacocinética , Fármacos Neuroprotetores/farmacologia , Plantas Medicinais/química , Plantas Medicinais/classificação
9.
J Huazhong Univ Sci Technolog Med Sci ; 37(3): 371-378, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28585133

RESUMO

The therapeutic potential of curcumin (Cur) is hampered by its poor aqueous solubility and low bioavailability. The aim of this study was to determine whether Cur nanoemulsions enhance the efficacy of Cur against prostate cancer cells and increase the oral absorption of Cur. Cur nanoemulsions were developed using the self-microemulsifying method and characterized by their morphology, droplet size and zeta potential. The results showed that the cytotoxicity and cell uptake were considerably increased with Cur nanoemulsions compared to free Cur. Cur nanoemulsions exhibited a significantly prolonged biological activity and demonstrated better therapeutic efficacy than free Cur, as assessed by apoptosis and cell cycle studies. In situ single-pass perfusion studies demonstrated higher effective permeability coefficient and absorption rate constant for Cur nanoemulsions than for free Cur. Our study suggested that Cur nanoemulsions can be used as an effective drug delivery system to enhance the anticancer effect and oral bioavailability of Cur.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Curcumina/farmacologia , Absorção Intestinal/efeitos dos fármacos , Nanoestruturas/administração & dosagem , Próstata/efeitos dos fármacos , Animais , Antineoplásicos Fitogênicos/farmacocinética , Apoptose/efeitos dos fármacos , Caspase 3/genética , Caspase 3/metabolismo , Caspase 7/genética , Caspase 7/metabolismo , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Curcumina/farmacocinética , Duodeno/efeitos dos fármacos , Duodeno/metabolismo , Emulsões , Expressão Gênica , Glicerol/química , Humanos , Íleo/efeitos dos fármacos , Íleo/metabolismo , Jejuno/efeitos dos fármacos , Jejuno/metabolismo , Masculino , Nanoestruturas/química , Tamanho da Partícula , Polietilenoglicóis/química , Próstata/metabolismo , Próstata/patologia , Ratos , Ratos Wistar , Tensoativos/química
10.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-333491

RESUMO

The therapeutic potential of curcumin (Cur) is hampered by its poor aqueous solubility and low bioavailability.The aim of this study was to determine whether Cur nanoemulsions enhance the efficacy of Cur against prostate cancer cells and increase the oral absorption of Cur.Cur nanoemulsions were developed using the self-microemulsifying method and characterized by their morphology,droplet size and zeta potential.The results showed that the cytotoxicity and cell uptake were considerably increased with Cur nanoemulsions compared to free Cur.Cur nanoemulsions exhibited a significantly prolonged biological activity and demonstrated better therapeutic efficacy than free Cur,as assessed by apoptosis and cell cycle studies.In siru single-pass perfusion studies demonstrated higher effective permeability coefficient and absorption rate constant for Cur nanoemulsions than for free Cur.Our study suggested that Cur nanoemulsions can be used as an effective drug delivery system to enhance the anticancer effect and oral bioavailability of Cur.

11.
Cancer Biother Radiopharm ; 29(8): 339-44, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25279971

RESUMO

UNLABELLED: Abstract Aims: To investigate the effect of chloride intracellular channel 1 (CLIC1) on the proliferation, migration, and apoptosis of prostate cancer cell lines PC-3 and DU145 and the possible molecular mechanisms. MATERIALS AND METHODS: Using the technique of RNA interference, the expression of CLIC1 was downregulated in the PC-3 and DU145 cell lines. MTT assay, Transwell chamber, and flow cytometry were used to determine the effect of CLIC1 on the proliferation, migration, and apoptosis ability of PC-3 and DU145 cells. The levels of phosphorylated extracellular signal-regulated kinase 1/2 (p-ERK1/2), ERK1/2, matrix metalloproteinase (MMP)-2, and MMP-9 were examined by western blotting. RESULTS: The results showed that the knockdown of CLIC1 exerts inhibitory effects on the proliferation and migration of PC-3 and DU145 cells. At the same time, the authors found that the knockdown of CLIC1 has no effect on the apoptosis in PC-3 and DU145 cells. Meanwhile, the levels of p-ERK1/2, MMP-2, and MMP-9 were decreased in the CLIC1 small interfering RNA (siRNA) group compared with the control and vector groups. CONCLUSION: These results indicate that CLIC1 could regulate prostate cancer cell proliferation and migration by regulating the mitogen-activated protein kinase (MAPK)/ERK pathway and offers a candidate molecular target for prostate cancer prevention and therapy.


Assuntos
Canais de Cloreto/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Apoptose/fisiologia , Processos de Crescimento Celular/fisiologia , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Canais de Cloreto/genética , Humanos , Masculino , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Neoplasias da Próstata/enzimologia , Neoplasias da Próstata/genética , Interferência de RNA , Transfecção
12.
Zhong Yao Cai ; 36(3): 468-71, 2013 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-24010331

RESUMO

OBJECTIVE: To optimize the prescription and technique for preparing saikoside (SS) liposomes and evaluate its quality. METHODS: The preparation methods of liposomes included film dispersion, ether injection, reverse phase evaporation and pH gradients were explored. The encapsulation ratio was determined by macroreticular resin method. The main factors affecting encapsulation ratio were studied by single factor analysis and central composite design. RESULTS: The appearance of SS liposomes prepared by optimized method was satisfactory. The encapsulation ratio was more than 60% and the verage particle size of SS liposomes was 110 nm. CONCLUSION: The formulation and preparation process is practical and simple for the preparation of SS liposomes. It is valuable to be further studied.


Assuntos
Bupleurum/química , Lipossomos/química , Ácido Oleanólico/análogos & derivados , Fosfolipídeos/administração & dosagem , Saponinas/administração & dosagem , Colesterol/administração & dosagem , Colesterol/química , Ácido Cítrico/química , Portadores de Fármacos/química , Ácido Oleanólico/administração & dosagem , Ácido Oleanólico/química , Tamanho da Partícula , Fosfolipídeos/química , Raízes de Plantas/química , Resinas Sintéticas , Saponinas/química
13.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 4): m184, 2013 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-23633988

RESUMO

In the title complex, [Ni(C9H5O6)2(C11H10N4)2]·8H2O, the Ni(II) ion exhibits site symmetry 2. It has a distorted octa-hedral coordination defined by two N atoms from two symmetry-related 1-[(1H-benzimidazol-1-yl)meth-yl]-1H-imidazole ligands and four O atoms from two symmetry-related 3,5-dicarb-oxy-benzoate anions. In the crystal, the complex mol-ecules and solvent water mol-ecules are linked via O-H⋯O, O-H⋯N and N-H⋯O hydrogen bonds, forming a three-dimensional structure. There are also a number of C-H⋯O inter-actions present.

14.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 9): m1150, 2012 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-22969452

RESUMO

In the title complex, {[CaZn(C(10)H(2)O(8))(H(2)O)(2)]·H(2)O}(n), the Zn(II) ion is coordinated by four O atoms from four benzene-1,2,4,5-tetra-carboxyl-ate anions in a distorted tetra-hedral geometry. The Ca(II) ion is eight-coordinated by six O atoms from four benzene-1,2,4,5-tetra-carboxyl-ate anions and by two water mol-ecules in a distorted square-anti-prismatic geometry. The Ca(II) and Zn(II) ions and the lattice water mol-ecule are located on twofold rotation axes; the centroid of the benzene-1,2,4,5-tetra-carboxyl-ate anion is located on a centre of inversion. The µ(8)-bridging mode of the anion results in the formation of a three-dimensional structure with channels extending along [100] in which lattice water mol-ecules are situated. Inter-molecular O-H⋯O hydrogen bonds involving the coordinating and lattice water mol-ecules as donors and the carboxyl-ate O atoms and lattice water mol-ecules as acceptors are present in the structure.

15.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 6): m801-2, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-22719349

RESUMO

There are three independent Cd(II) ions in the title complex, {[Cd(3)(C(10)H(3)O(8))(2)(H(2)O)(4)]·4H(2)O}(n), one of which is coordinated by four O atoms from three 5-carboxybenzene-1,2,4-tri-carboxyl-ate ligands and by two water mol-ecules in a distorted octa-hedral geometry. The second Cd(II) ion is coordinated by five O atoms from four 5-carboxybenzene-1,2,4-tri-carboxyl-ate ligands and by one water mol-ecule also in a distorted octa-hedral geometry while the third Cd(II) ion is coordinated by five O atoms from three 5-carboxybenzene-1,2,4-tri-carboxyl-ate ligands and by one water mol-ecule in a highly distorted octa-hedral geometry. The 5-carboxybenzene-1,2,4-tri-carboxyl-ate ligands bridge the Cd(II) ions, resulting in the formation of a three-dimensional structure. Intra- and inter-molecular O-H⋯O hydrogen bonds are present throughout the three-dimensional structure.

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