title: Molecular basis of the interaction of novel tributyltin(IV) 2/4-[(E)-2-(aryl)-1-diazenyl]benzoates endowed with an improved cytotoxic profile: synthesis, structure, biological efficacy and QSAR studies.
abstract: A series of tributyltin(IV) complexes based on 2/4-[(E)-2-(aryl)-1-diazenyl]benzoate ligands was synthesized, wherein the position of the carboxylate and aryl substituents (methyl, tert-butyl and hydroxyl) varies. The complexes, Bu(3)SnL(1-4)H (1-4), have been structurally characterized by elemental analysis and IR, NMR ((1)H, (13)C, and (119)Sn) and (119)Sn Mössbauer spectroscopy. All have a tetrahedral geometry in solution and a trigonal bipyramidal geometry in the solid-state, except for Bu(3)SnL(4)H (4) that was ascertained to have tetrahedral coordination by X-ray crystallography. Cytotoxicity studies were carried out on human tumor cell lines A498 (renal cancer), EVSA-T (mammary cancer), H226 (non-small-cell lung cancer), IGROV (ovarian cancer), M19 MEL (melanoma), MCF-7 (mammary cancer) and WIDR (colon cancer). Compared to cisplatin, test compounds 1-4 had remarkably good activity, despite the presence of substantial steric bulk due to Sn-Bu ligands. The quantitative structure-activity relationship (QSAR) studies for the cytotoxicity of organotin(IV) benzoates, along with some reference drug molecules, is also discussed against a panel of human tumor cell lines. Molecular structures of the tributyltin(IV) complexes (1-4) were fully optimized using the PM6 semi-empirical method and docking studies performed with key enzymes associated with the propagation of cancer, namely ribonucleotide reductase, thymidylate synthase, thymidylate phosphorylase and topoisomerase II. The theoretical results are discussed in relation to the mechanistic role of the cytotoxic active test compounds (1-4).
authors.affiliation: Department of Chemistry, North-Eastern Hill University, NEHU Permanent Campus, Umshing, Shillong 793 022, India. basubaul@nehu.ac.in
authors.forename: Tushar S
authors.initials: TS
authors.lastname: Basu Baul
authors.forename: Anup
authors.initials: A
authors.lastname: Paul
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Pellerito
authors.forename: Michelangelo
authors.initials: M
authors.lastname: Scopelliti
authors.forename: Claudia
authors.initials: C
authors.lastname: Pellerito
authors.forename: Palwinder
authors.initials: P
authors.lastname: Singh
authors.forename: Pooja
authors.initials: P
authors.lastname: Verma
authors.forename: Andrew
authors.initials: A
authors.lastname: Duthie
authors.forename: Dick
authors.initials: D
authors.lastname: de Vos
authors.forename: Rajeshwar P
authors.initials: RP
authors.lastname: Verma
authors.forename: Ulli
authors.initials: U
authors.lastname: Englert
mesh_terms: D000970:Antineoplastic Agents / Q000138:chemical synthesis* / Q000737:chemistry* / Q000494:pharmacology; D001565:Benzoates / Q000737:chemistry*; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D018360:Crystallography, X-Ray; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D015394:Molecular Structure; D009947:Organotin Compounds / Q000138:chemical synthesis* / Q000737:chemistry* / Q000494:pharmacology; D021281:Quantitative Structure-Activity Relationship; D014220:Trialkyltin Compounds / Q000737:chemistry*
chemical_list: D000970:Antineoplastic Agents; D001565:Benzoates; D009947:Organotin Compounds; D014220:Trialkyltin Compounds; C011559:tributyltin