15227-42-6Relevant articles and documents
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.
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.
Chiral nanostructuring of multivalent macrocycles in solution and on surfaces
Caricato, Marco,Delforge, Arnaud,Bonifazi, Davide,Dondi, Daniele,Mazzanti, Andrea,Pasini, Dario
supporting information, p. 3593 - 3601 (2015/03/30)
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.
