کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1316238 976438 2011 11 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Influence of pyridine versus piperidine ligands on the chemical, DNA binding and cytotoxic properties of light activated trans,trans,trans-[Pt(N3)2(OH)2(NH3)(L)]
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی معدنی
پیش نمایش صفحه اول مقاله
Influence of pyridine versus piperidine ligands on the chemical, DNA binding and cytotoxic properties of light activated trans,trans,trans-[Pt(N3)2(OH)2(NH3)(L)]
چکیده انگلیسی

The photocytotoxicity and photobiochemical properties of the new complex trans,trans,trans-[Pt(N3)2(OH)2(NH3)(piperidine)] (5) are compared with its analogue containing the less basic and less lipophilic ligand pyridine (4). The log P (n-octanol/water) values were of −1.16 and −1.84 for the piperidine and pyridine complexes, respectively, confirmed that piperidine increases the hydrophobicity of the complex. Density Functional Theory (DFT) and time-dependent density functional theory (TDDFT) calculations indicate that 5 has accessible singlet and triplet states which can promote ligand dissociation when populated by both UVA and visible white light. When activated by UVA or white light, both compounds showed similar cytotoxic potencies in various human cancer cell lines although their selectivity was different. The time needed to reach similar antiproliferative activity was noticeably decreased by introducing the piperidine ligand. Neither compound showed cross-resistance in three oxoplatin-resistant cell lines. Furthermore, both compounds showed similar anticlonogenic activity when activated by UVA radiation. Interactions of the light-activated complexes with DNA showed similar kinetics and levels of DNA platination and similar levels of DNA interstrand cross-linking (ca. 5%). Also the ability to unwind double stranded DNA were comparable for the piperidine analogue (24°, respectively), while the piperidine complex showed higher potency in changing the conformation of DNA, as measured in an ethidium bromide binding assay. These results indicate that the nature of the heterocyclic nitrogen ligand can have subtle influences on both the phototoxicity and photobiochemistry of this class of photochemotherapeutic agents.

Graphical AbstractStructure–activity relationships show that neither the basicity nor the aromaticity of the liganding amine (L) in [Pt(N3)2(OH)2(NH3)(L)] is responsible for good photoactivation to cytotoxic species but rather the bulkiness of the amine ligand.Figure optionsDownload as PowerPoint slide

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Inorganic Biochemistry - Volume 105, Issue 5, May 2011, Pages 652–662
نویسندگان
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