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1.
Chemphyschem ; 24(17): e202300159, 2023 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-37349282

RESUMEN

Fluorescence imaging is conducive to establish a bridge between molecular biology and clinical medicine, and provides new tools for disease process research, early diagnosis, and efficacy evaluation, because of the advantages of rapid imaging and nondestructive detection. Herein, a series of fluorescent molecules with thiadiazole, or thiazole, or benzothiazole cores were designed and synthesized to develop more excellent fluorescent molecules in bio-imaging. According to theoretical and experimental methods, we found that benzothiazole derivative 14 B with conjugate expansion by (4-aminophenyl) ethynyl group was the most excellent fluorescent molecule among all the investigated compounds and exhibited low cytotoxicity and strong blue and green fluorescence by confocal cell imaging.


Asunto(s)
Benzotiazoles , Tiadiazoles , Benzotiazoles/química , Colorantes , Fluorescencia , Colorantes Fluorescentes/química
2.
Acta Pharmacol Sin ; 44(11): 2296-2306, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37316630

RESUMEN

Current therapy for acute myeloid leukemia (AML) is largely hindered by the development of drug resistance of commonly used chemotherapy drugs, including cytarabine, daunorubicin, and idarubicin. In this study, we investigated the molecular mechanisms underlying the chemotherapy drug resistance and potential strategy to improve the efficacy of these drugs against AML. By analyzing data from ex vivo drug-response and multi-omics profiling public data for AML, we identified autophagy activation as a potential target in chemotherapy-resistant patients. In THP-1 and MV-4-11 cell lines, knockdown of autophagy-regulated genes ATG5 or MAP1LC3B significantly enhanced AML cell sensitivity to the chemotherapy drugs cytarabine, daunorubicin, and idarubicin. In silico screening, we found that chloroquine phosphate mimicked autophagy inactivation. We showed that chloroquine phosphate dose-dependently down-regulated the autophagy pathway in MV-4-11 cells. Furthermore, chloroquine phosphate exerted a synergistic antitumor effect with the chemotherapy drugs in vitro and in vivo. These results highlight autophagy activation as a drug resistance mechanism and the combination therapy of chloroquine phosphate and chemotherapy drugs can enhance anti-AML efficacy.


Asunto(s)
Idarrubicina , Leucemia Mieloide Aguda , Humanos , Idarrubicina/farmacología , Idarrubicina/uso terapéutico , Leucemia Mieloide Aguda/tratamiento farmacológico , Daunorrubicina/farmacología , Daunorrubicina/uso terapéutico , Citarabina/farmacología , Citarabina/uso terapéutico , Autofagia , Cloroquina/farmacología , Cloroquina/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico
3.
Drug Dev Ind Pharm ; 47(8): 1279-1289, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34605344

RESUMEN

PURPOSE: Through the method of network pharmacology, the active components and targets of Shenqi Wan (SQW) were excavated, the relationship with novel Coronavirus pneumonia (COVID-19) was discussed, and the possible mechanism of SQW in the treatment of COVID-19 was revealed from the aspects of multicomponents, multitargets, and multipathways. METHODS: Firstly, the active components of SQW were screened from traditional Chinese medicine systems pharmacology database and analysis platform and the 2020 edition of Chinese Pharmacopeia, and the related targets of the components were obtained. Then the disease targets related to COVID-19 were screened from GeneCards and Online Mendelian Inheritance in Man. Venny was used to map the relationship between component-target and disease-target, and String was used to analyze the interaction of common targets. The network was constructed and analyzed by Cytoscape, the function of Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) genes was enriched by Metascape, and the molecular docking was verified by CB-Dock. RESULTS: Finally, 45 active components of SQW were obtained, and 72 potential targets were related to COVID-19, angiotensin-converting enzyme 2 (ACE2), interleukin (IL)-6, nitric oxide synthase (NOS3) and, C-reactive protein (CRP),may be the key targets. GO enrichment of 1715 projects, such as lipopolysaccharide stress response, active oxygen metabolism, positive regulation of cell migration, and other GO enrichment. About 136 KEGG pathways, tumor necrosis factor signaling pathway, IL-17 signaling pathway, hypoxia-inducible factor 1-α signaling pathway were obtained. Molecular docking showed that kaempferol, quercetin, luteolin, astragaloside, calyx isoflavone glucoside, matrine, and other COVID-19-related targets such as ACE2, chymotrypsin-like protease (3CLpro), papain-like protease (PLpro), prostaglandin-endoperoxide synthase 2 (PTGS2) have good binding ability. CONCLUSION: According to the above results, it is suggested that SQW may play a role in the treatment of COVID-19 by directly or indirectly combining kaempferol, quercetin, and luteolin with ACE2, 3CLpro, PLpro, and PTGS2 to regulate multiple biological functions and signaling pathways.


Asunto(s)
Tratamiento Farmacológico de COVID-19 , Medicamentos Herbarios Chinos , Enzima Convertidora de Angiotensina 2 , Ciclooxigenasa 2 , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/uso terapéutico , Humanos , Luteolina , Medicina Tradicional China/métodos , Simulación del Acoplamiento Molecular , Farmacología en Red , Quercetina
4.
Zhongguo Zhong Yao Za Zhi ; 46(10): 2403-2412, 2021 May.
Artículo en Zh | MEDLINE | ID: mdl-34047084

RESUMEN

To investigate the potential molecular mechanism of the combination of Platycodonis Radix and Lilii Bulbus with the homology of medicine and food in the treatment of pneumonia by means of network pharmacology and in vitro verification experiment. Under the condition of bioavailability(OB)≥30% and drug-like(DL)≥0.18, the active components of Platycodonis Radix and Lilii Bulbus were screened in TCMSP database; the prediction targets of active components were searched from TCMSP, DrugBank and other databases, and the potential targets of pneumonia were obtained through GeneCards and OMIM database. The common targets were obtained by the intersection of drug and disease targets. The PPI network of common targets was constructed by STRING 11.0, and the core targets were obtained by topological analysis. Then the core targets received GO and KEGG analysis with use of WebGestalt and Metascape. The "component-target-pathway" network was constructed with the help of Cytoscape 3.7.1 software, and the component-target molecular docking verification was carried out with Discovery Studio 2016 software. Finally, the core targets and pathways were preliminarily verified in vitro. In this study, 12 active components were screened, 225 drug prediction targets and 420 potential diseases targets were obtained based on data mining method, and 14 core targets were obtained by topological analysis, including TNF, MMP9, AKT1, IL4 and IL2. The enrichment results of GO and KEGG showed that "Platycodonis Radix and Lilii Bulbus" drug pair may regulate inflammation, cell growth and metabolism by acting on 20 key signaling pathways such as TNF and IL-17, thereby exerting anti-pneumonia effects. The results of molecular docking showed that 12 active components had good binding ability with 14 core targets. In vitro experiment results showed that the core components of "Platycodonis Radix and Lilii Bulbus" drug pair could inhibit the expression of MMP9 and TNF-α by regulating TNF signal pathway. This study confirmed the scientificity and reliability of the prediction results of network pharmacology, and preliminarily revealed the potential molecular mechanism of the compatibility of Platycodonis Radix and Lilii Bulbus in the treatment of pneumonia. It provides a novel insight on systematically exploring the mechanism of the compatible use of Platycodonis Radix and Lilii Bulbus, and has a certain reference value for the research, development and application of new drugs.


Asunto(s)
Medicamentos Herbarios Chinos , Neumonía , Humanos , Medicina Tradicional China , Simulación del Acoplamiento Molecular , Neumonía/tratamiento farmacológico , Reproducibilidad de los Resultados
5.
Angew Chem Int Ed Engl ; 58(48): 17194-17198, 2019 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-31538687

RESUMEN

Excellent nonlinear optical materials simultaneously meet the requirements of large SHG response, phase-matching capability, wide transparency windows, considerable energy band-gap, good thermal stability and structure stability. Herein, two new promising nonlinear optical (NLO) crystals LiMII (IO3 )3 (MII =Zn and Cd) are rationally designed by the aliovalent substitution strategy from the commercialized α-LiIO3 with the perfect parallel alignment of IO3 groups. Compared with parent α-LiIO3 and related AI 2 MIV (IO3 )6 , the title compounds exhibit more stable covalent 3D structure, and overcome the racemic twinning problem of AI 2 MIV (IO3 )6 . More importantly, both compounds inherit NLO-favorable structure merits of α-LiIO3 and show larger SHG response (≈14× and ≈12×KDP), shorter absorption edge (294 and 297 nm) with wider energy band-gap (4.21 and 4.18 eV), good thermal stability (460 and 430 °C), phase-matching behaviors, wider optical transparency window and good structure stability, achieving an excellent balance of NLO properties.

6.
J Chem Phys ; 145(3): 034304, 2016 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-27448884

RESUMEN

The ground state vibrational energy and spatial features of (4)He-(4)He-Li(+) and its triatomic isotopic complexes are studied using the slow variable discretization (SVD) method in the hyperspherical coordinates for the zero total angular momentum. Our results show that the dominant structure of the system is an isosceles triangle with the shorter side associated with the two Li(+)-He distances using the sum-of-potential approximation. Corrections caused by the induced dipole-induced dipole interactions on the He atoms are also investigated. The effects are seen to be small and have a minor influence on the binding energy and the structure of present system. The results are also compared with the full ab initio calculations including all the three-body interactions and information of three-body corrections is obtained.

7.
Inorg Chem ; 53(8): 4130-43, 2014 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-24712729

RESUMEN

Seven cupric halide coordination polymers, namely [Cu5(OH)3Br3(ina)4] (1), [Cu5(OH)3Cl3(ina)4] (2), [Cu2(OH)Cl(ina)2] (3), [Cu3(OH)2Cl2(ina)2]·2H2O (4), [Cu3(OH)2Br2(ina)2]·2H2O (5), [Cu2Cl2(ina)2(H2O)2] (6), [Cu2Cl(ina)2(gca)(H2O)] (7), cupric complex templated cuprous halide [Cu(II)(Me-ina)2(H2O)][Cu(I)5Br7] (8), and organic templated cuprous halide Me2-ina[Cu2Br3] (9) (Hina = isonicotinic acid), were prepared from the starting materials of cupric halide and Hina via fine-tuning solvothermal reactions. According to valence states of copper, 1-7 are copper(II) complexes, 8 is a mixed-valent Cu(I,II) complex, while 9 is a Cu(I) compound. According to bonding types of halides, nine complexes can be classified as three types: complexes 1-3 include only normal X-Cu bond (X = halide); complexes 4-7 include normal X-Cu bond and X···Cu weak bond; complexes 8 and 9 include normal X-Cu bond and X···H-C halogen hydrogen bonds. Complexes 1 and 2 are isomorphic three-dimensional (3D) pcu topological metal organic frameworks (MOFs) with butterfly-like Cu4(µ3-OH)2X2 and steplike Cu6(µ3-OH)4 cores as nodes, showing strong ferromagnetic couplings. Complex 3 also is a pcu topological MOF with only butterfly-like Cu4(µ3-OH)2Cl2 clusters as nodes, presenting spin canting antiferromagnetic behavior. Isostructural 4 and 5 are Cu3(OH)2 clusters based two-dimensional (2D) (4,4) layers, which are extended into 3D eight-connected networks via weak Cu···X bonds, showing ferromagnetic coupling. Antiferromagnetic 6 is a simple one-dimensional coordination polymer, which is extended via weak Cu···Cl bonds into 3D (3,4)-connected networks. Paramagnetic 7 is a ladderlike polymer, which is extended into 2D (3,4)-connected layer via weak Cu···Cl bonds. The syntheses of polymeric cupric complexes 1-7 mainly result from differences in reactant ratio and pH value. Utilization of reducing methanol generated novel cubane-containing [Cu5Br7](2-) chain templated by paddlewheel-like [Cu(II)(Me-ina)2](2+) 8 and face-shared dimer-containing [Cu2Br3](-) chain templated by N-methylated and O-esterificated Me2-ina 9. Complex 9 exhibits a strong red emission and a weaker green emission upon excitation.

8.
Huan Jing Ke Xue ; 45(9): 5395-5405, 2024 Sep 08.
Artículo en Zh | MEDLINE | ID: mdl-39323157

RESUMEN

With the drying and warming of the climate and irrational grazing, various types of grasslands in Inner Mongolia have been degraded to different degrees, and different management modes will inevitably affect the plant diversity and vegetation carbon stock of soil grasslands. To clarify the changes and influencing factors of plant diversity and carbon stock in different types of grasslands under different management modes, plant species composition, aboveground biomass, and vegetation carbon were analyzed based on 18 sentinel monitoring stations across three different types of grasslands in Inner Mongolia. The results showed that grazing increased the dominance of typical grassland and desert grassland, whereas meadow grassland decreased, and the evenness index and Shannon Wiener diversity index increased less in meadow grassland and desert grassland. Grazing decreased graminaceous biomass in meadow grassland and typical grassland, whereas it increased in desert grassland. Above-ground vegetation and below-ground root carbon stocks were much higher than those in grazing areas, 1.5 and 1.2 higher, respectively, but vegetation carbon stocks in long-term grazing sites were significantly lower than those in short-term grazing. Further, the structural equations showed that the effects of geographic location, climatic factors, and soil factors on the biomass and vegetation carbon stocks of the three grassland types differed significantly. The results can provide a reference for the ecologically sustainable development of grassland and the optimization of management mode.


Asunto(s)
Biodiversidad , Carbono , Pradera , Poaceae , Carbono/análisis , China , Poaceae/crecimiento & desarrollo , Herbivoria , Animales , Biomasa , Conservación de los Recursos Naturales , Suelo/química
9.
Eur J Med Chem ; 265: 116027, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38128236

RESUMEN

The Src homology 2 domain-containing protein tyrosine phosphatase 1 (SHP1) is a convergent node for oncogenic cell-signaling cascades. Consequently, SHP1 represents a potential target for drug development in cancer treatment. The development of efficient methods for rapidly tracing and modulating the SHP1 activity in complex biological systems is of considerable significance for advancing the integration of diagnosis and treatment of the related disease. Thus, we designed and synthesized a series of imidazo[1,2,4] triazole derivatives containing salicylic acid to explore novel scaffolds with inhibitory activities and good fluorescence properties for SHP1. The photophysical properties and inhibitory activities of these imidazo[1,2,4] triazole derivatives (5a-5y) against SHP1PTP were thoroughly studied from the theoretical simulation and experimental application aspects. The representative compound 5p exhibited remarkable fluorescence response (P: 0.002) with fluorescence quantum yield (QY) of 0.37 and inhibitory rate of 85.21 ± 5.17% against SHP1PTP at the concentration of 100 µM. Furthermore, compound 5p showed obvious aggregation caused quenching (ACQ) effect and had high selectivity for Fe3+ ions, good anti-interference and relatively low detection limit (5.55 µM). Finally, the cellular imaging test of compound 5p also exhibited good biocompatibility and certain potential biological imaging application. This study provides a potential way to develop molecules with fluorescent properties and bioactivities for SHP1.


Asunto(s)
Proteínas Tirosina Fosfatasas , Transducción de Señal , Fluorescencia , Proteína Tirosina Fosfatasa no Receptora Tipo 6/metabolismo , Triazoles/farmacología
10.
Artículo en Inglés | MEDLINE | ID: mdl-24098173

RESUMEN

In the title compound, {(C4H12N)[Mn(HCO2)3]} n , the Mn(II) atom lies on an inversion centre and is coordinated by O-atom donors from the three double-bridging formate ligands, one of which lies across a crystallographic mirror plane, giving a slightly distorted octahedral coordination sphere. A three-dimensional NaCl-type framework is generated in which the tetra-methyl-ammonium cations, which lie across mirror planes and occupy the cavities in the polymer structure, form weak C-H⋯O hydrogen bonds with the formate ligands.

11.
mBio ; 13(1): e0000422, 2021 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-35164563

RESUMEN

Combination treatments are commonly prescribed for enhancing drug efficacy, as well as for preventing the evolution of resistance. The interaction between drugs is typically evaluated near the MIC, using growth rate as a measure of treatment efficacy. However, for infections in which the killing activity of the treatment is important, measurements far above the MIC are needed. In this regime, the killing rate often becomes weakly concentration dependent, and a different metric is needed to characterize drug interactions. We evaluate the interaction metric on killing using an easy visual assay, the interaction tolerance detection test (iTDtest), that estimates the survival of bacteria under antibiotic combinations. We identify antibiotic combinations that enable the eradication of tolerant bacteria. Furthermore, the visualization of the antibiotic interactions reveals directional drug interactions and enables predicting high-order combination outcomes, therefore facilitating the determination of optimal treatments. IMPORTANCE The killing efficacy of antibiotic combinations is rarely measured in the clinical setting. However, in cases where the treatment is required to kill the infecting organism and not merely arrest its growth, the information on the killing efficacy is important, especially when tolerant strains are implicated. Here, we report on an easy method for the determination of the killing efficacy of antibiotic combinations which enabled to reveal combinations effective against tolerant bacteria. The results could be generally used to guide antimicrobial therapy in life-threatening infections.


Asunto(s)
Antibacterianos , Pruebas de Sensibilidad Microbiana
12.
Dalton Trans ; 48(35): 13423-13429, 2019 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-31433416

RESUMEN

Silver doped TiO2 (Ag-TiO2) materials show high activity and good stability in photocatalysis, but the mechanism could not be illustrated clearly due to their imprecise and inhomogeneous characteristics. Ag-doped titanium-oxo clusters (Ag-TOCs) with an exact crystal structure, which are rarely reported, are beneficial for further understanding structure-property relationships. Herein, six new Ag-TOCs with a butterfly-like Ti8Ag2 core have been synthesized through facile solvothermal reactions, in which two Ag ions are successfully linked to the surface of the Ti8 core. Of interest, the Ti6 unit of the Ti8Ag2 core is similar to that found in the anatase structure and may be a promising model for Ag-TiO2 materials. The band gaps of these Ag-TOCs show different values mainly affected by different ligands. DFT calculations revealed that the lowest energy bands of Ag-TOCs are attributed to the Ag-to-TiO core charge transfer bands. Additionally, all Ag-TOCs exhibit good photoelectric response and high photodegradation activity towards organic dyes.

13.
Sci Rep ; 7(1): 15929, 2017 11 21.
Artículo en Inglés | MEDLINE | ID: mdl-29162879

RESUMEN

MicroRNA-30e (miR-30e) is downregulated in various tumor types. However, its mechanism in inhibiting tumor growth of breast cancer remains to be elucidated. In this study, we found that miR-30e was significantly downregulated in tumor tissues of breast cancer (BC) patients and cell lines, and overexpression of miR-30e inhibited cell proliferation, migration and invasion. To understand the potential mechanism of miR-30e in inhibiting tumor growth, we showed that miR-30e blocked the activation of AKT and ERK1/2 pathways, and the expression of HIF-1α and VEGF via directly targeting IRS1. Moreover, miR-30e regulates cell proliferation, migration, invasion and increases chemosensitivity of MDA-MB-231 cells to paclitaxel by inhibiting its target IRS1. MiR-30e also inhibited tumor growth and suppressed expression of IRS1, AKT, ERK1/2 and HIF-1α in mouse xenograft tumors. To test the clinical relevance of these results, we used 40 pairs of BC tissues and adjacent normal tissues, analyzed the levels of miR-30e and IRS1 expression in these tissues, and found that miR-30e levels were significantly inversely correlated with IRS1 levels in these BC tissues, suggesting the important implication of our findings in translational application for BC diagnostics and treatment in the future.


Asunto(s)
Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Resistencia a Antineoplásicos , Proteínas Sustrato del Receptor de Insulina/metabolismo , MicroARNs/metabolismo , Animales , Secuencia de Bases , Neoplasias de la Mama/tratamiento farmacológico , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Movimiento Celular/genética , Proliferación Celular/efectos de los fármacos , Proliferación Celular/genética , Regulación hacia Abajo/efectos de los fármacos , Regulación hacia Abajo/genética , Resistencia a Antineoplásicos/efectos de los fármacos , Resistencia a Antineoplásicos/genética , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Células HEK293 , Humanos , Masculino , Ratones Endogámicos BALB C , Ratones Desnudos , MicroARNs/genética , Invasividad Neoplásica , Paclitaxel/farmacología , Paclitaxel/uso terapéutico , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal/efectos de los fármacos
14.
Oncotarget ; 7(24): 36940-36955, 2016 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-27175587

RESUMEN

It is currently known that estrogen plays an important role in breast cancer (BC) development, but the underlying molecular mechanism remains to be elucidated. Accumulating evidence has revealed important roles of microRNAs in various kinds of human cancers, including BC. In this study, we found that among the microRNAs regulated by estrogen, miR-124 was the most prominent downregulated miRNA. miR-124 was downregulated by estradiol (E2) treatment in estrogen receptor (ER) positive BC cells, miR-124 overexpression suppressed cell proliferation, migration and invasion in BC cells; while the suppression of miR-124 using Anti-miR-124 inhibitor had opposite cellular functions. Under the E2 treatment, miR-124 had stronger effect to inhibit cellular functions in MCF7 cells than that in MDA-MB-231 cells. In addition, we identified that ERα, but not ERß, was required for E2-induced miR-124 downregulation. Furthermore, AKT2, a known oncogene, was a novel direct target of miR-124. AKT2 expression levels were inversely correlated with miR-124 expression levels in human breast cancer specimens. AKT2 was overexpressed in BC specimens, and its expression levels were much higher in ERα positive cancer tissues than those ERα negative cancer tissues. Consistent with miR-124 suppression, E2 treatment increased AKT2 expression levels in MCF7 cells via ERα. Finally, overexpression of miR-124 in MCF7 cells significantly suppressed tumor growth and angiogenesis by targeting AKT2. Our results provide a mechanistic insight into a functional role of new ERα/miR-124/AKT2 signaling pathway in BC development. miR-124 and AKT2 may be used as biomarkers for ERα positive BC and therapeutic effect in the future.


Asunto(s)
Neoplasias de la Mama/patología , Estradiol/metabolismo , Receptor alfa de Estrógeno/metabolismo , Regulación Neoplásica de la Expresión Génica/fisiología , MicroARNs/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Animales , Neoplasias de la Mama/genética , Movimiento Celular/genética , Estradiol/farmacología , Femenino , Xenoinjertos , Humanos , Ratones , Ratones Desnudos , MicroARNs/genética , Invasividad Neoplásica/genética , Neovascularización Patológica/genética , Neovascularización Patológica/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética
15.
Dalton Trans ; 44(46): 19796-9, 2015 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-26541095

RESUMEN

The reversible crystal transformation between the mononuclear complex [Cu(tzbc)2(H2O)4] (1) and the 4-fold interpenetrated diamondoid MOF [Cu(tzbc)2] (2) was chemically implemented and structurally interpreted. Interestingly, despite 4-fold interpenetration, desolvated with 1D channels and rich N-groups shows exclusive CO2 adsorption of up to 12.5 wt% at room temperature and low pressure, indicating potential application in the separation of industrial and automobile exhaust.

16.
Chem Asian J ; 8(7): 1587-95, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23625460

RESUMEN

By using environmentally friendly [Ni(CN)4](2-) as a cyanide source, three new heterometallic cyano-bridged mixed-valence Cu(I)/Cu(II) coordination polymers with three different electronic configurations (d(8)-d(10)), that is, [Cu2Ni(CN)5(H2O)3] (1), [Cu2Ni(CN)5(pn)H2O] (2), and [Cu3Ni(CN)6(pn)2] (3, pn = 1,2-propane diamine) have been synthesized by gradually increasing the amount of pn. Compound 1, which was hydrothermally synthesized in the absence of pn ligand, exhibits the famous 2D Cairo pentagonal tiling, in which the Cu(I), Cu(II), and Ni(II) atoms act as trigonal, T-shaped, and square-planar nodes, respectively. Notably, there are three water molecules located at the meridianal positions of the octahedrally coordinated Cu(II) atom in compound 1. A similar reaction, except for the addition of a small amount of pn, generated a similar Cairo pentagonal tiling layer in which two of the water molecules that were located at the meridianal positions of the octahedrally coordinated Cu(II) atom were replaced by a chelating pn group. Another similar hydrothermal reaction, with the addition of a larger amount of pn, yielded compound 3, which showed a related two-fold-interpenetrated (3,4)-connected 3D framework with an unprecedented {8(3)}2{8(6)} topology in which the Cu(II) atom was chelated by two pn groups. These structural changes between compounds 1-3 can be explained by the chelating effect of the pn group. The replacement of two meridianally coordinated water molecules on the octahedral Cu(II) atom in compound 1 by a pn group gives compound 2, which shows similar Cairo tiling, and a further increase in the amount of pn results in the formation of the [Cu(NC)2(pn)2] unit and the two-fold-interpenetrated 3D framework of compound 3. The mixed-valence properties of compounds 1, 2, and 3 were confirmed by variable-temperature magnetic-susceptibility measurements.

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