14024-97-6Relevant articles and documents
Application of microwave-assisted heating to the synthesis of Pt(II) complexes
Gabano, Elisabetta,Gama, Sofia,Mendes, Filipa,Fregonese, Federico,Paulo, António,Ravera, Mauro
, p. 16 - 19 (2015)
The microwave-assisted synthesis of Pt(II) complexes containing several pyridines (i.e., pyridine L1, 2-picoline L2, 3-picoline L3, 4-picoline L4, 2,2′-bipyridine L5) is reported. For L1-L5, the reaction was successful in about 50% yield with all the ligands except L2. The same method applied to 4,4′-bis(2-morpholinoethoxy)-2,2′-bipyridine (L6, a ligand showing interesting antiproliferative properties because of a high DNA affinity), was unsatisfactory. The corresponding complex cis-[PtCl2(L6)] was obtained only heating at reflux a mixture of [PtCl2(1,5-cyclooctadiene)] and L6 in acetonitrile for 24 h. Antiproliferative activity of [PtCl2(L6)] on four cancer cell lines (ovarian A2780 and its cisplatin-resistant variant A2780cisR, prostate PC3 and breast cancer MDA-MB-231) was compared with that of its ligand and the model complex [PtCl2(L5)]. These studies showed that [PtCl2(L6)] has just marginal activity towards the tested cells if compared with cisplatin.
Near-infrared light-mediated photoactivation of a platinum antitumor prodrug and simultaneous cellular apoptosis imaging by upconversion-luminescent nanoparticles
Min, Yuanzeng,Li, Jinming,Liu, Fang,Yeow, Edwin K. L.,Xing, Bengang
, p. 1012 - 1016 (2014)
Platinum-based drugs are among the most active antitumor reagents in clinical practice; their application is limited by side effects and drug resistance. A novel and personalized near-infrared (NIR) light-activated nanoplatform is obtained by combining a photoactivatable platinum(IV) prodrug and a caspase imaging peptide conjugated with silica-coated upconversion- luminescent nanoparticles (UCNPs) for the remote control of antitumor platinum prodrug activation, and simultaneously for real-time imaging of apoptosis induced by activated cytotoxicity. Upon NIR light illumination, the Pt IV prodrug complex is activated at the surface of the nanoparticle and active components are selectively released which display cytotoxicity against human ovarian carcinoma A2780 cells and its cisplatin-resistant variant A2780cis cells. More importantly, the caspases enzymes triggered by cytotoxicity would effectively cleave the probe peptide, thereby allowing the direct imaging of apoptosis in living cells. Platinum-based drugs: Near-infrared (NIR) light illumination of conjugates made of photoactive platinum(IV) prodrugs and upconversion-luminescent nanoparticles (UCNPs) is used for the remotely controlled activation of antitumor effects and for simultaneous initiation of apoptosis in the targeted tumor cells. The apoptosis-dependent caspase-3 enzyme offers the promising possibility of imaging apoptosis in real time. Copyright
Acid-Base Equilibria of Co-ordinated Ligands. Part 1. The Effect of Basicity of Co-ordinated Nitrogen Donors upon the Acidity of Chelating 8-Aminoquinoline in some Dicationic Platinum(II) Complexes
Annibale, Giuliano,Cattalini, Lucio,Guidi, Francesca
, p. 731 - 734 (1994)
Cationic complexes of the type 2 and 2 (8NH2-quin = 8-aminoquinoline), where L and L-L are mono- and bi-dentate nitrogen donors respectively, have been prepared.In aqueous solution, they undergo reversible
trans-Dichlorotetrakis(pyridine)platinum(IV) Nitrate: a Classical Co-ordination Compound
Seddon, Kenneth R.,Turp, Janet E.,Constable, Edwin C.,Wernberg, Ole
, p. 293 - 296 (1987)
Claims that trans-dichlorotetrakis(pyridine)platinum(IV) nitrate forms a covalent hydrate when dissolved in water are shown to be in error; the observed acidity of the aqueous solution is due to the presence of a small amount of a strongly acidic impurity, and all of the observed physical and spectroscopic properties of the salt are simply interpreted in terms of classical co-ordination chemistry.
Chiral nanostructuring of multivalent macrocycles in solution and on surfaces
Caricato, Marco,Delforge, Arnaud,Bonifazi, Davide,Dondi, Daniele,Mazzanti, Andrea,Pasini, Dario
, p. 3593 - 3601 (2015)
We describe the design and synthesis of a novel functionality-rich, homochiral macrocycle, possessing the overall molecular D2 symmetry, in which multivalency is introduced into the covalent framework by means of four suitably positioned pyridine moieties. The macrocycle synthesis is carried out with functionalized, enantiopure 1,1′-binaphthyl synthons as the source of chirality by means of a room temperature esterification reaction as the cyclization procedure. Upon addition of Pd2+, coordination of the pyridine moieties occurs both intra and intermolecularly, to afford chiral ordered mono and dimeric macrocycles or multimeric aggregates depending on the solvents and conditions used. The metal binding event takes place in combination with a significant macrocyclic conformational rearrangement detected by circular dichroism spectroscopy. When in combination with a third component (C60), the macrocycle-Pd2+ hybrid undergoes surface-confined nanostructuring into chiral nanofibres.
Platinum(iv)-azido monocarboxylato complexes are photocytotoxic under irradiation with visible light
Butler, Jennifer S.,Clarkson, Guy,Farrer, Nicola J.,Habtemariam, Abraha,Romero, Mar?a J.,Romero-Canelón, Isolda,Sadler, Peter J.,Salassa, Luca,Shaili, Evyenia,Woods, Julie A.
supporting information, p. 10593 - 10607 (2021/08/09)
Complexestrans,trans,trans-[Pt(N3)2(OH)(OCOR)(py)2] where py = pyridine and where OCOR = succinate (1); 4-oxo-4-propoxybutanoate (2) andN-methylisatoate (3) have been synthesized by derivation oftrans,trans,trans-[Pt(OH)2(N3)2(py)2] (4) and characterised by NMR and EPR spectroscopy, ESI-MS and X-ray crystallography. Irradiation of1-3with green (517 nm) light initiated photoreduction to Pt(ii) and release of the axial ligands at a 3-fold faster rate than for4. TD-DFT calculations showed dissociative transitions at longer wavelengths for1compared to4. Complexes1and2showed greater photocytotoxicity than4when irradiated with 420 nm light (A2780 cell line IC50values: 2.7 and 3.7 μM) and complex2was particularly active towards the cisplatin-resistant cell line A2780cis (IC503.7 μM). Unlike4, complexes1-3were phototoxic under green light irradiation (517 nm), with minimal toxicity in the dark. A pKa(H2O) of 5.13 for the free carboxylate group was determined for1, corresponding to an overall negative charge during biological experiments, which crucially, did not appear to impede cellular accumulation and photocytotoxicity.
The synthesis, structure-toxicity relationship of cisplatin derivatives for the mechanism research of cisplatin-induced nephrotoxicity
Hu, Jing,Wu, Tian-Ming,Li, Hong-Ze,Zuo, Ze-Ping,Zhao, Ying-Lan,Yang, Li
, p. 3591 - 3594 (2017/07/07)
Cisplatin is a widely used antineoplastic drug, while its nephrotoxicity limits the clinical application. Although several mechanisms contributing to nephrotoxicity have been reported, the direct protein targets are unclear. Herein we reported the synthesis of 29 cisplatin derivatives and the structure-toxicity relationship (STR) of these compounds with MTT assay in human renal proximal tubule cells (HK-2) and pig kidney epithelial cells (LLC-PK1). To the best of our knowledge, this study represented the first report regarding the structure-toxicity relationship (STR) of cisplatin derivatives. The potency of biotin-pyridine conjugated derivative 3 met the requirement for target identification, and the preliminary chemical proteomics results suggested that it is a promising tool for further target identification of cisplatin-induced nephrotoxicity.
Synthesis and Characterization of Pt(II) Complexes with Pyridyl Ligands: Elongated Octahedral Ion Pairs and Other Factors Influencing 1H NMR Spectra
Lewis, Nerissa A.,Pakhomova, Svetlana,Marzilli, Patricia A.,Marzilli, Luigi G.
supporting information, p. 9781 - 9793 (2017/08/26)
Our goal is to develop convenient methods for obtaining trans-[PtII(4-Xpy)2Cl2] complexes applicable to 4-substituted pyridines (4-Xpy) with limited volatility and water solubility, properties typical of 4-Xpy, with X being a moiety targeting drug delivery. Treatment of cis-[PtII(DMSO)2Cl2] (DMSO = dimethyl sulfoxide) with 4-Xpy in acetonitrile allowed isolation of a new series of simple trans-[PtII(4-Xpy)2Cl2] complexes. A side product with very downfield H2/6 signals led to our synthesis of a series of new [PtII(4-Xpy)4]Cl2 salts. For both series in CDCl3, the size of the H2/6 δ[coordinated minus free 4-Xpy H2/6 shift] decreased as 4-Xpy donor ability increased from 4-CNpy to 4-Me2Npy. This finding can be attributed to the greater synergistic reduction in the inductive effect of the Pt(II) center with increased 4-Xpy donor ability. The high solubility of [PtII(4-Xpy)4]Cl2 salts in CDCl3 (a solvent with low polarity) and the very downfield shift of the [PtII(4-Xpy)4]Cl2 H2/6 signals for the solutions provide evidence for the presence of strong {[PtII(4-Xpy)4]2+,2Cl-} ion pairs that are stabilized by multiple CH···Cl contacts. This conclusion gains considerable support from [PtII(4-Xpy)4]Cl2 crystal structures revealing that a chloride anion occupies a pseudoaxial position with nonbonding (py)C-H···Cl contacts (2.4-3.0 ?). Evidence for (py)C-H···Y contacts was obtained in NMR studies of [PtII(4-Xpy)4]Y2 salts with Y counterions less capable of forming H-bonds than chloride ion. Our synthetic approaches and spectroscopic analysis are clearly applicable to other nonvolatile ligands.
Compound with antitumor activity, and preparation method and application thereof
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Paragraph 0094; 0095; 0096; 0100, (2017/12/28)
The invention provides a compound with antitumor activity, and a preparation method and application thereof, and relates to the technical field of chemical compounding drugs. The compound is of a structure shown as a formula (I) or (II). The stimuli-responsive self-assembly unimolecular compound with the antitumor activity is prepared through condensation reaction between hepatic-targeting water-soluble lactose and a platinum (IV) compound. The compound has the advantages that hepatic-targeting water-soluble lactose molecules are introduced, water-solubility of the platinum (IV) compound is improved, and hydrophilic-lyophobic balance is achieved, so that the self-assembly unimolecular platinum (IV) compound is formed, cytotoxicity of the platinum (IV) compound is reduced, a compounded tetravalence platinum prodrug has amphipathy, and accumulation degree of hepatoma cells can be increased; due to platinum, activation and release of the platinum compound are benefited under the conditions of external photostimulation or intracellular reduction, and accordingly, high antitumor activity is achieved.
Effect of catalyst structure on the reaction of α-methylstyrene with 1,1,3,3-tetramethyldisiloxane
De Vekki,Skvortsov
, p. 762 - 777 (2009/09/26)
Reaction of α-methylstyrene with 1,1,3,3-tetramethyldisiloxane in the presence of the complexes of platinum(II), palladium(II) and rhodium(I) is explored. It is established that in the presence of platinum catalyst predominantly occurs hydrosilylation of α-methylstyrene leading to formation of β-adduct, on palladium catalysts proceeds reduction of α-methylstyrene, on rhodium catalysts both the processes take place. In the reaction mixture proceeds disproportion and dehydrocondensation of 1,1,3,3-tetramethyldisiloxane that leads to formation of long chain linear and cyclic siloxanes of general formula HMe2Si(OSiMe2) n H and (-OSiMe2-)m (n = 2-6, m = 3-7), respectively. Platinum catalysts promotes formation of linear siloxanes, while both rhodium and palladium catalysts afford linear and cyclic siloxanes as well. Structure of intermediate metallocomplexes is studied.
