768-05-8Relevant articles and documents
A discrete dysprosium trigonal prism showing single-molecule magnet behaviour
Tian, Haiquan,Wang, Min,Zhao, Lang,Guo, Yun-Nan,Guo, Yang,Tang, Jinkui,Liu, Zhiliang
, p. 442 - 445 (2012)
A magnetic personality: A unique dysprosium trigonal prism with a new polydentate Schiff-base ligand behaves as a single molecule magnet (SMM), which may stimulate further investigations into the relaxation dynamics of SMMs with different topologies (see
A chromone based Schiff base: An efficient colorimetric sensor for specific detection of Cu (II) ion in real water samples
Tomer, Nisha,Goel, Apurva,Ghule, Vikas D.,Malhotra, Rajesh
, (2021)
A new chromone based Schiff base ligand L was synthesized by the condensation of 3-formyl chromone and pyrazine-2-carbohydrazide as a colorimetric probe to detect Cu (II) ions selectively. An instant visual colour change from colourless to yellow was obtained on addition of Cu2+ ions to the probe L solution, while other metal ions found ineffective. The ligand L was characterized by 1H NMR, FTIR and HRMS spectral techniques. UV-Visible spectroscopic technique was used to study the sensing ability of probe L for copper ions above other metal ions. The Job's plot obtained from absorption studies and HRMS data confirmed that the Cu2+ ions bind with ligand L in 1:1 stoichiometric ratio. DFT computations were also supported the binding framework between L and Cu (II) ions. The LOD value and the association constant were obtained 3.9 × 10?7 M and 2.3 × 105 M?1 respectively, via Benesi-Hildebrand equation. Selectivity of L towards Cu2+ ions was also studied and it was found that the probe L worked specifically for copper ions without any considerable influence of other intruding metal ions. In addition, in real water samples, the ligand L was fully implemented for identification and quantification of Cu2+ ions.
New silver(I) phosphino complexes: Evaluation of their potential as prospective agents against Mycobacterium tuberculosis
Maldonado, Yndira Dolores,Scalese, Gonzalo,Manieri, Karyn Fernanda,Pavan, Fernando R.,Aguirre Méndez, Larry D.,Gambino, Dinorah
, (2021/12/14)
Despite being a preventable and curable disease, Tuberculosis (TB) is the world's top infectious killer. Development of new drugs is urgently needed. In this work, the synthesis and characterization of new silver(I) complexes, that include N′-[(E)-(pyridine-2-ylmethylene)pyrazine-2-carbohydrazide, HPCPH, as main ligand and substituted aryl-phosphines as auxiliary ligands, is reported. HPCPH was synthesized from pyrazinoic acid, the active metabolite of the first-line antimycobacterial drug pyrazinamide. Complexes [Ag(HPCPH)(PPh3)2]OTf (1), [Ag(HPCPH)((P(p-tolyl)3)2]OTf (2) and [Ag(HPCPH)(P(p-anisyl)3)2]OTf (3) were characterized in solid state and in solution by elemental analysis and FTIR and NMR spectroscopies (OTf[dbnd]triflate). Crystal structures of (1,2) were determined by XRD. The Ag atom is coordinated to azomethine and pyridine nitrogen atoms of HPCPH ligand and to the phosphorous atom of each aryl-phosphine co-ligand. Although HPCPH did not show activity, the Ag(I) compounds demonstrated activity against Mycobacterium tuberculosis (MTB), H37Rv strain, and multi-drug resistant clinical isolates (MDR-TB). Globally, results showed that the compounds are not only effective against the sensitive strain, but are more potent against MDR-TB than antimycobacterial drugs used in therapy. The compounds showed low to moderate selectivity index values (SI) towards the bacteria, using MRC-5 cells (ATCC CCL-171) as mammalian cell model. Interaction with DNA was explored to get insight into the potential mechanism of action against the pathogen. No significant interaction was detected, allowing to discard this biomolecule as a potential molecular target. Compound 1 was identified as a hit compound (MIC90 2.23 μM; SI 4.4) to develop further chemical modifications in the search for new drugs.
A chromone hydrazide Schiff base fluorescence probe with high selectivity and sensitivity for the detection and discrimination of human serum albumin (HSA) and bovine serum albumin (BSA)
Yan, Xiao-Jing,Li, Zhe,Liu, Hai-Bo,Wang, Zhi-Gang,Fan, Jing,Xie, Cheng-Zhi,Li, Qing-Zhong,Xu, Jing-Yuan
, (2021/10/12)
The discrimination and identification of human serum albumin (HSA) and bovine serum albumin (BSA) is very important, which is due to the vital roles of two SAs in biological and pharmaceutical research. Based on structural screening and docking calculation from a series of homologues, a coumarin Schiff base fluorescent probe 3-hydroxy-N′-((4-oxo-4H-chromen-3-yl)methylene)-2-naphthohydrazide (HCNH) has been designed and synthesized, which could effectively discriminate HSA and BSA. The probe HCNH exhibited superior sensitivity toward HSA and BSA with the detection limits of 10.62 nM and 16.03 nM in PBS solution, respectively. The binding mechanism of HCNH with SAs was studied by Job's plot analysis, SA destruction and displacement assay. Molecular docking and DFT methods were utilized to provide deep insight into the spatial conformation change of HCNH and binding sites in HSA/BSA. The conformation of HCNH was significantly influenced by the microenvironment provided by HSA and BSA, therefore its fluorescence emission was affected correspondingly. Non-toxic probe HCNH could be successfully used for fluorescence bio-imaging of HSA in cancer cells, which is significantly different from normal cells and favors the application in medical diagnosis.
