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1.
Inorg Chem ; 58(18): 11903-11911, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31192594

RESUMO

Four hexanuclear circular helicates, {[Dy6L6(DMF)12]·6CF3SO3·12DMF}2 (1Dy), {[Gd6L6(DMF)12]·6CF3SO3·12DMF}2 (1Gd), [Dy6L6(DMF)10(H2O)2]·6ClO4·4H2O·10DMF (2Dy), and [Gd6L6(DMF)12]·6ClO4·2H2O·10DMF (2Gd), where DMF = N,N-dimethylformamide, were synthesized by employing a glutaratedihydrazide-bridged bis(3-methoxysalicylaldehyde) ligand (H2L) and characterized structurally and magnetically. Direct-current magnetic susceptibility studies indicated predominant weak antiferromagnetic exchange interactions among gadolinium analogues, which were quantified using the PHI software, giving J = -0.003 cm-1 with g = 2.00 for 1Gd and J = -0.001 cm-1 with g = 2.02 for 2Gd. Alternating-current magnetic susceptibility measurements indicated that complexes 1Dy and 2Dy show slow relaxation of magnetization behavior, further supported by theoretical calculations that also highlighted the toroidal arrangement of the magnetic moments.

2.
Inorg Chem ; 58(9): 5715-5724, 2019 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-30969114

RESUMO

Six tetranuclear DyIII complexes [Dy4(L)2(CH3OH)3(NO3)3]·3NO3·2H2O (1a), [Dy4(L)2(CH3OH)2(SCN)4(OCH3)2]·2CH3OH·2H2O (1b), {[Dy4(L)2(CH3OH)(SCN)6(CH3CN)]·3CH3OH·4CH3CN}2 (2a), [Dy4(L)2(CH3OH)2(SCN)6]·6CH3OH·2H2O (2b), [Dy4(L)2(CH3OH)2(SCN)4(OCH3)2]·5CH3OH·2H2O (3a), and [Dy4(L)2(CH3OH)(SCN)5(H2O)2]·SCN·4CH3OH·2H2O (3b) were structurally and magnetically characterized. The Dy1/Dy2 centers in these complexes are eight-coordinate and submitted to pseudo- D4d symmetry environments. It is noteworthy that the modulation of coordination terminal around Dy1/Dy2 centers induces distinct magnetic relaxation processes, switching from single relaxation (1b) to two-step relaxation (2b). All complexes show significant zero-field single-molecule magnet (SMM) properties with the exception of 3b, which only features the slow magnetic relaxation behavior under a zero dc field. Ab initio calculations substantiate that the excellent SMM property of complex 1b should mainly profit from strong ferromagnetic interactions between the individual DyIII ions, while different single-ion magnetism results in better SMM property of complex 3a than that of 3b.

3.
Molecules ; 24(1)2019 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-30621360

RESUMO

A series of thiophene derivatives (TPs) were synthesized and evaluated for cytotoxicity in HepG2 and SMMC-7721 cell lines by MTT assay. TP 5 was identified as a potential anticancer agent based on its ability to inhibit tumor cell growth. Drawbacks of TPs, including poor solubility and high toxicity, were overcome through delivery using self-assembling HSA nanoparticles (NPs). The optimum conditions for TP 5-NPs synthesis obtained by adjusting the temperature and concentration of TP 5. The NPs had an encapsulation efficiency of 99.59% and drug-loading capacity of 3.70%. TP 5 was slowly released from TP 5-NPs in vitro over 120 h. HepG2 and SMMC-7721 cell lines were employed to study cytotoxicity of TP 5-NPs, which exhibited high potency. ROS levels were elevated and mitochondrial membrane potentials reversed when the two cell lines were treated with TP 5-NPs for 12 h. Cellular uptake of fluorescence-labeled TP 5-NPs in vitro was analyzed by flow cytometry and laser confocal scanning microscopy. Fluorescence intensity increased over time, suggesting that TP 5-NPs were efficiently taken up by tumor cells. In conclusion, TP 5-NPs showed great promise as an anticancer therapeutic agent.


Assuntos
Albuminas/química , Antineoplásicos/farmacologia , Portadores de Fármacos/química , Nanopartículas/química , Tiofenos/farmacologia , Transporte Biológico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Preparações de Ação Retardada/química , Desenho de Drogas , Liberação Controlada de Fármacos , Humanos , Estrutura Molecular , Tamanho da Partícula , Espécies Reativas de Oxigênio/metabolismo , Solubilidade , Relação Estrutura-Atividade , Propriedades de Superfície
4.
Chem Commun (Camb) ; 54(85): 12097-12100, 2018 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-30302449

RESUMO

Structurally unique double-shelled 4f and 3d-4f supramolecular grids were constructed and assembled into 3D hydrogen-bonded organic frameworks (HOFs), with the 3d-4f heterometallic HOF showing single-molecule magnet (SMM) behaviour.

5.
Acta Biochim Pol ; 65(3): 465-470, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30188965

RESUMO

Inflammation plays an important role in the development of many obesity-related diseases. This study aimed to investigate the effect of ezetimibe on inflammation and myocardial remodeling in obese rats. A rat model of obesity was established, and myocardial damage was examined by transmission electron microscopy and Masson staining. Twenty obese rats were divided into two groups (n=10): obese group and ezetimibe group. Ten SD rats were used as controls. Western blot was performed to monitor the expression of P-p38MAPK and interleukin (IL)-6. Immunohistochemical staining was used to monitor the expression of intercellular adhesion molecule-1 and vascular cell adhesion molecule-1. In the obese rats group, we observed increased inflammatory factors and myocardial hypertrophy. In contrast, the ezetimibe group exhibited decreased expression of inflammatory factors and an improvement in myocardial remodeling compared to the obese group. Mechanistically, we found that ezetimibe decreased P-p38MAPK, IL-6, intercellular adhesion molecule-1, and vascular cell adhesion molecule-1 levels in the hearts of the obese rats. Taken together, these results indicate that ezetimibe may improve myocardial remodeling in obese rats by inhibiting inflammation.

6.
Chem Commun (Camb) ; 54(69): 9655-9658, 2018 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-30101273
7.
Cell Physiol Biochem ; 48(5): 1843-1853, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30092566

RESUMO

BACKGROUND/AIMS: Consumption of a high-fat (HF) diet exacerbates metabolic cardiomyopathy through lipotoxic mechanisms. In this study, we explored the role of aldehyde dehydrogenase-2 (ALDH2) in myocardial damage induced by a HF diet. METHODS: Wild-type C57 BL/6J mice were fed a HF diet or control diet for 16 weeks. ALDH2 overexpression was achieved by injecting a lentiviral ALDH2 expression vector into the left ventricle. RESULTS: Consumption of a HF diet induced metabolic syndrome and myocardial remodeling, and these deleterious effects were attenuated by ALDH2 overexpression. In addition, ALDH2 overexpression attenuated the cellular apoptosis and insulin resistance associated with a HF diet. Mechanistically, ALDH2 overexpression inhibited the expression of c-Jun N-terminal kinase (JNK)-1, activated protein 1 (AP-1), insulin receptor substrate 1 (IRS-1), 4- hydroxynonenal, caspase 3, transforming growth factor ß1, and collagen I and III, and enhanced Akt phosphorylation. CONCLUSION: ALDH2 may effectively attenuate myocardial remodeling and contractile defects induced by a HF diet through the regulation of the JNK/AP-1 and IRS-1/Akt signaling pathways. Our study demonstrates that ALDH2 plays an essential role in protecting cardiac function from lipotoxic cardiomyopathy.


Assuntos
Aldeído-Desidrogenase Mitocondrial/metabolismo , Dieta Hiperlipídica , Miocárdio/metabolismo , Aldeído-Desidrogenase Mitocondrial/genética , Animais , Apoptose , Proteínas Substratos do Receptor de Insulina/metabolismo , Resistência à Insulina , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Potencial da Membrana Mitocondrial , Síndrome Metabólica/etiologia , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Contração Miocárdica , Miocárdio/patologia , Estresse Oxidativo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Fator de Transcrição AP-1/metabolismo , Remodelação Ventricular
8.
Front Pharmacol ; 9: 464, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29867472

RESUMO

Atherosclerosis (AS) in diabetic patients is often associated with low stability, which might be largely attributed to unfavorable macrophage polarization and increased inflammatory response induced by hyperglycaemia. Ginsenoside Rg3 is one of the main active principles of Panax Ginseng, which has been reported to be a natural ligand of peroxisome proliferator-activated receptor-gamma (PPARγ), a key nuclear transcriptional factor involved in inflammation and macrophage differentiation. However, it remains unclear if Rg3 could exert protective effects on plaque stability in diabetes. In this study, we investigated the role of ginsenoside 20(S)-Rg3 in macrophage polarization and AS plaque stability using advanced glycation end products-treated macrophages and diabetic AS mice models. In vitro, advanced glycation end products (AGEs) treatment promoted the expression of proinflammatory molecules and M1 surface markers, whereas 20(S)-Rg3 could reverse the M1 polarization to the M2 phenotype. In vivo, the administration of 20(S)-Rg3 promoted AS lesion stability and reduced the plaque burden, accompanied by increased M2 macrophages and reduced M1 macrophages. In addition, PPARγ antagonist GW9662 co-administration mostly blocked these effects, suggesting the important role of PPARγ pathways in mediating 20(S)-Rg3 effects in macrophage polarization and atherosclerosis progression. Together, these results demonstrated an immunomodulatory role of ginsenoside 20(S)-Rg3 in promoting macrophages to a profile of the M2 type through PPARγ-dependent mechanisms, and indicated a potential role of 20(S)-Rg3 in the prevention and treatment of diabetic atherosclerosis.

9.
Chemistry ; 24(39): 9928-9939, 2018 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-29697161

RESUMO

The magnetic relaxation and magnetization blocking barriers of tailor-made homo- and heterodinuclear compounds [Dy2 (opch)2 (OAc)2 (H2 O)2 ]⋅MeOH (1) and [DyMn(opch)2 (OAc)(MeOH)(H2 O)2 ] (2), where H2 opch is (E)-N'-(2-hydroxy-3-methoxybenzylidene)pyrazine-2-carbohydrazide, were systematically investigated and the change in single-molecule magnet behavior originating from targeted replacement of one dysprosium site in the Dy2 compound with manganese was elucidated through a combination of experimental and theoretical studies. A detailed comparative study on these closely related model compounds revealed remarkable changes of the crystal-field splitting and anisotropy of the Dy site and the total exchange spectrum due to the replacement of Dy by Mn. The blocking barriers of these two compounds, which explain their different relaxation behaviors, were analyzed. The two Ising doublets arising from the magnetic interaction in the case of 1 are strongly uniaxial, with tunneling splittings smaller than 10-6  cm-1 , and this leads to magnetic relaxation at temperatures exceeding the exchange energy (2.14 cm-1 ), which involves transition via the excited states corresponding to local transitions on the excited doublet at the Dy site. The third and fourth exchange doublets in 2 (located at 2.16 and 3.25 cm-1 , respectively) show much larger tunneling splittings (of 10-4 and 10-3  cm-1 , respectively), and thus open an important path for magnetic relaxation.

10.
Dalton Trans ; 47(10): 3321-3328, 2018 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-29423466

RESUMO

Magnetic nitrogenous cobalt-carbon composites were synthesized via calcination of N-ZIF-67, where metal and N atoms were introduced into the conductive carbon matrix formed during carbonization of N-ZIF-67, and were applied, as catalysts, in the reduction reaction of p-nitrophenol, assisted by NaBH4. Characterization of the prepared composites was carefully performed using SEM, TEM, XRD, SQUID magnetometric analysis, XPS and nitrogen adsorption/desorption measurements. Compared to Co@C, which was similarly prepared, the N-Co@C catalyst exhibits much better catalytic activity for the reduction of 4-nitrophenol to 4-aminophenol. The pseudo-first-order rate constant for the N-Co@C catalyst is 4.47 times greater than that for the Co@C catalyst, and its stability shows little change after five reaction cycles. The superior catalytic properties of the N-Co@C catalyst are due to the presence of N moieties. Leaching out the cobalt cores was induced using FeCl3 and HCl to see what the active centers were. The results show that the majority of the catalytic activity is associated with the metal cores.

11.
Chem Commun (Camb) ; 54(9): 1065-1068, 2018 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-29323673

RESUMO

Toroidal arrangements of magnetic moments are realized in heterometallic Ln6Cu6 (Ln = Tb and Dy) macrocycles thanks to the magnetic coupling between lanthanide and 3d metal ions.

12.
Biosens Bioelectron ; 99: 28-33, 2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-28735043

RESUMO

In this work, we have developed an electrochemical aptasensor for high-sensitivity determination of carcinoembryonic antigen (CEA) based on lead ion (Pb2+)-dependent DNAzyme-assisted signal amplification and graphene quantum dot-ionic liquid-nafion (GQDs-IL-NF) composite film. We designed hairpin DNA containing CEA-specific aptamers and DNAzyme chains. In the presence of CEA, hairpin DNA recognized the target and performed a DNAzyme-assisted signal amplification reaction to yield a large number of single-stranded DNA. The GQDs-IL-NF composite film was immobilized on the glassy carbon electrode for the interaction with single-stranded DNA through noncovalent π-π stacking interaction. Therefore, the methylene blue-labeled substrate DNA (MB-substrate) was fixed on the electrode and exhibited an initial electrochemical signal. Under optimal conditions, the response current change was proportional to the concentration of CEA, demonstrating a wide linear range from 0.5fgmL-1 to 0.5ngmL-1, with a low detection limit of 0.34fgmL-1. Furthermore, the proposed aptasensor was successfully applied in determining CEA in serum samples, showing its superior prospects in clinical diagnosis.


Assuntos
Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais , Antígeno Carcinoembrionário/isolamento & purificação , DNA Catalítico/química , Antígeno Carcinoembrionário/sangue , DNA de Cadeia Simples/química , Polímeros de Fluorcarboneto/química , Ouro/química , Grafite/química , Humanos , Líquidos Iônicos , Limite de Detecção , Nanoestruturas/química , Pontos Quânticos/química
13.
Inorg Chem ; 56(18): 11211-11219, 2017 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-28853556

RESUMO

A series of mononuclear DyIII complexes with the general formula [DyLz2(salicylaldehyde)2]·X·solvent (Lz = 6-pyridin-2-yl[1,3,5]triazine-2,4-diamine; X = OH- (1·OH), Cl- (2·Cl), Br- (3·Br)) have been synthesized using mixed salicylaldehyde/pyridinyl-triazine ligands and discriminative counteranions. The DyIII ion in these three complexes resides in a similar D4d coordination geometry with counteranions perturbing the coordination environment and bond lengths and angles in the lattice. Magnetostructural studies reveal that the asymmetric distribution of salicylaldehyde/pyridinyl-triazine ligands and the presence of discriminative counteranions result in the coexistence of large anisotropy and quantum tunneling of magnetization. The magnetic anisotropy is dominated by the axial ligand field with short Dy-Osali distances and large ∠Osali-Dy-Osali angles, while the quantum tunneling relaxation is probably dictated by the π-π stacking of the Lz ligands, which induces an axial constriction of the coordinating plane. Ab initio calculations substantiate the diversity of the magnetic behaviors in these complexes and highlight the importance of axial ligand field with short Dy-Osali distances, large ∠Osali-Dy-Osali angles and less ligand stacking in these pseudo-D4d-symmetrical single-molecule magnets.

14.
Inorg Chem ; 56(14): 7882-7889, 2017 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-28665118

RESUMO

As the simplest entity carrying intramolecular magnetic interactions, a dinuclear lanthanide complex serves as a model to investigate the effects of magnetic interactions on relaxation of magnetization, and importantly, it proves to be an efficient method to obtain robust single-molecule magnets via improving the communication between lanthanide centers. Here, three Dy2 complexes (1, 2, 3) with a similar structural motif, namely, [Dy2(HL)2(NO3)2(CH3CN)2]·2CH3CN (1), [Dy2(HL)2(NO3)2(DMF)2]·2H2O (2), and Dy2(HL)2(NO3)2(DMF)4 (3), were successfully assembled. One critical difference found in this series of complexes is that the Dy center in complex 3 is coordinated by one more solvent molecule. Surprisingly, complex 3 exhibits the best magnet-like behavior, as evidenced by the high effective barrier and butterfly-type hysteresis, although the crystal field effect around Dy ions is weakened heavily. Ab initio calculations revealed the crucial reason is the significant synergic effect between single-ion anisotropy and magnetic interactions, i.e., not only the axiality of the Dy ion is improved efficiently but also the exchange magnetic interactions increased to the same order of magnitude to the dipolar interaction in 3. This effect mainly benefits from the elaborate modification of the local coordinate environment around the Dy ion, which results in a special arrangement of anisotropy axes different from the other two complexes. It demonstrates that the magnetic interactions could be effectively enhanced by means of deliberate local structural modulation.

15.
Biosens Bioelectron ; 98: 386-391, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-28709088

RESUMO

MicroRNA 21 (MIR21) has garnered much attention in recent years as an important disease biomarker. The detection of it in human system shows great significance for the healthy evaluation and major diseases early detection. Herein, a novel approach tactfully manipulates the in-situ precise preparation of copper nanoclusters on overlapping Y-shaped ds-DNA for MIR21 analysis were developed in the proposed integrated aptasensor. In the presence of target MIR21, overlapping Y-shaped ds-DNA was constructed on electrode. Copper nanoclusters were in-situ prepared on this effective template for target detection. Taking advantage of exonuclease T7 triggered targets recycling, hybridization chain reaction (HCR) and copper nanoclusters triple amplification strategy, linear detection of MIR21 was achieved from 10pM to 0.1fM with a detection limit down to 10aM (S/N > 3). This approach provides a good model for integrating both synthesis and detection into one electrochemistry component. It showed promising potential for applications in aptamer related target detection in human serum analysis.


Assuntos
Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Nanopartículas Metálicas/química , MicroRNAs/isolamento & purificação , Aptâmeros de Nucleotídeos/genética , Cobre/química , Técnicas Eletroquímicas/métodos , Exonucleases/química , Exonucleases/genética , Humanos , MicroRNAs/genética
16.
Dalton Trans ; 46(25): 8252-8258, 2017 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-28612868

RESUMO

Geometry and magnetic interaction modulations in a series of dinuclear dysprosium compounds, [Dy2Lz2(OAc)6]·2CH3OH (1), [Dy2Lz2(C6H5CO2)6]·2CH3CN (2), and [Dy2L2(SO3CF3)4THF4] (3) (Lz = 6-pyridin-2-yl-[1,3,5]triazine-2,4-diamine; L = N-(2,3-dimethylbut-3-en-2-yl)-N-hydroxynitrous amide; THF = tetrahydrofuran), can effectively tune the relaxation dynamics of magnetization. The dysprosium centres of compounds 2 and 3 display a hula hoop-like geometry; however, those in 1 show the monocapped square antiprismatic geometries. Moreover, the Dy2 cores of compounds 1 and 3 were linked by µ2-η1:η1 and µ2-η1:η2 bridging modes, thus generating shorter intramolecular DyDy distances as compared to those in compound 2. Consequently, these three compounds demonstrate distinct magnetic properties. Compounds 1 and 2 behave as single-molecule magnets (SMMs) under an appropriate static dc field; in addition, 2 displays field-induced multiple relaxation processes under a 1000 Oe dc field. Compound 3 shows a high relaxation energy barrier of 102 K in the zero dc field. These three interesting compounds with Dy2 cores shed light on the coordination geometry and magnetic interactions for the modulation of the properties of SMMs.

17.
Inorg Chem ; 56(7): 4104-4111, 2017 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-28290670

RESUMO

A series 1.Ln of tetranuclear lanthanide clusters [Ln4(µ4-O)L2(PhCOO)6]·solvent (Ln = Gd (1.Gd), Dy (1.Dy), Ho (1.Ho)) and octanuclear lanthanide Ln4 cluster pairs 2.Ln [Ln8(µ3-OH)4(CO3)2L4(PhCOO)8]·solvent (Ln = Gd (2.Gd), Dy (2.Dy), Tb (2.Tb)) were assembled by using a bi-Schiff-based ligand H2L and characterized structurally and magnetically. Interestingly, the octanuclear Ln4 cluster pairs 2.Ln are proposed to be assembled from the tetranuclear clusters 1.Ln through the uptake of CO2 from air in a more basic media. X-ray structural analyses approved the possible evolution mechanism. Magnetic studies reveal the coexistence of ferro- and anti-ferromagnetic interaction in 1.Gd and 2.Gd by simulating the direct-current magnetic susceptibility and indicate the CO32- bridges produce weak ferromagnetic interaction in 2.Gd rather than anti-ferromagnetic interaction by benzoate bridges in 1.Gd. The magnitude of the magnetocaloric effect has been examined and shows that complex 2.Gd exhibits larger magnetocaloric effect than 1.Gd, which could be probably ascribed to the weak ferromagnetic interaction produced by the CO32- bridges.

18.
Chem Commun (Camb) ; 53(21): 3026-3029, 2017 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-28239723

RESUMO

A rare end-to-end azido-pinned interlocking lanthanide square was self-assembled using a ditopic Schiff-base (H2L) and NaN3 as ligands. Obvious ferromagnetic interaction and a record anisotropy barrier of 152(4) K among lanthanide azido-bridged SMMs in a zero dc field were observed.

19.
Dalton Trans ; 46(5): 1577-1584, 2017 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-28091655

RESUMO

Three µ4-O bridged Dy4 squares, {[Dy4(µ4-O)(HL1)4(H2O)4]2(NO3)3(OH)}·2H2O·2CH3OH (1), [Dy4(µ4-O)(HL2)4(SCN)2]·2H2O·4CH3OH (2) and [Dy4(µ4-O)(H2L3)2(SCN)2]·6H2O (3) were assembled by using a Schiff base ligand and its dimerized and reduced congener, respectively. These complexes share a similar µ4-O bridged Dy4 core, while, both the coordination geometry and metal-ligand interactions are slightly changed upon the modulation of the ligands, resulting in distinct single-molecular magnetic (SMM) and single-molecular toroic (SMT) properties. In complex 1, the Schiff base ligands are in an antiparallel fashion and all DyIII ions are in a similar coordination geometry, realizing the toroidal arrangement of magnetic moments. For complex 2, the reduced ligand H3L2 in a parallel fashion results in double relaxation processes and a 9-fold increase of the Ueff. Interestingly, with the use of the dimerized ligand H6L3, we obtained complex 3, which is similar to complex 2, while due to the slight changes of the coordination environment both the single molecular magnetic property and toroidal magnetic moments almost disappeared.

20.
Dalton Trans ; 46(2): 564-570, 2017 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-27977026

RESUMO

Two new dysprosium complexes, [Dy(H5L)(NO3)2(CH3OH)2]·4CH3OH (1) and [Dy2(H5L)2(NO3)4(H2O)2]·10CH3OH (2), were isolated from the reaction of a novel 1,8-naphthalenediol-based ligand N,N'-((1,8-dihydroxynaphthalene-2,7-diyl)bis(methanylylidene))bis(2-hydroxybenzohydrazide), H6L with dysprosium(iii) nitrate upon crystallization at different temperatures. Because of a low-symmetrical coordination environment, both complexes display only field-induced single molecular magnetic (SMM) behavior. Interestingly, complex 2 containing two dysprosium ions shows field-induced multiple relaxation processes, whereas only one relaxation process is observed for complex 1. The remarkably different behavior observed in 2 is mainly ascribed to the weak intra- or intermolecular interactions between the two DyIII centres in this complex.

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