title: Crystal structures and cytotoxicity of isopropylamine Pt(II) complexes: a trinuclear squarato-bridged [Pt3(mu2-C4O4)3(H2NPri)6].3H2O and a mononuclear cis-[Pt(NO3)2(H2NPri)2].
abstract: Crystals of a novel platinum(II) complex with squarato ligand, [Pt(3)(mu(2)-C(4)O(4))(3)(H(2)NPr(i))(6)].3H(2)O (1) (H(2)NPr(i)=ipa), have been isolated from the aqueous solution of cis-[Pt(H(2)O)(2)(H(2)NPr(i))(2)]SO(4) and barium squarate. Slow evaporation of methanol solution of cis-[Pt(NO(3))(2)(H(2)NPr(i))(2)] (2) resulted in crystallization of nitrato complex. The single crystal X-ray diffraction method was used to determine structures of 1 and 2. Complex 1 crystallizes in a triclinic space group P1 with a=11.17380(10)A, b=14.4535(2)A, c=14.8010(2)A, alpha=86.0901(10) degrees , beta=78.4343(11) degrees , gamma=69.1915(5) degrees , and complex 2 in a monoclinic space group P2(1)/n, with a=10.1161(2)A, b=9.9188(2)A, c=13.3766(2)A, beta=102.7360(7) degrees . The X-ray structure analysis revealed that three platinum atoms in 1 are connected with three squarates which adopt bis(unidentate) binding modes. The squarato ligands span relatively long intramolecular Ptcdots, three dots, centeredPt distances (4.8842(3)-5.2699(3)A). A pair of cis positioned isopropylamine ligands completes a square planar coordination sphere of each Pt(II) ion. The square-planar coordination of complex 2 consists of two cis positioned isopropylamine ligands and two nitrato ligands. The results of cytotoxicity assay of trimer 1, monomer 2 and cis-diamminedichloroplatinum(II) (cisplatin) performed on human bladder tumor cell line T24 provide evidence that complex 2 is less cytotoxic compared to cisplatin and that the survival of tumor cells after exposure to 1 was minimally reduced.
authors.affiliation: Faculty of Chemistry and Chemical Technology, Department of Chemistry, University of Ljubljana, Slovenia. sabina.grabner@fkkt.uni-lj.si
authors.forename: Sabina
authors.initials: S
authors.lastname: Grabner
authors.forename: Barbara
authors.initials: B
authors.lastname: Modec
authors.forename: Maja
authors.initials: M
authors.lastname: Cemazar
authors.forename: Natasa
authors.initials: N
authors.lastname: Bukovec
mesh_terms: D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D002945:Cisplatin / Q000494:pharmacology; D003460:Crystallization; D018360:Crystallography, X-Ray; D004354:Drug Screening Assays, Antitumor; D006572:Heterocyclic Compounds, Bridged-Ring / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology; D006801:Humans; D008024:Ligands; D008958:Models, Molecular; D009944:Organoplatinum Compounds / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology; D010984:Platinum / Q000737:chemistry*; D011437:Propylamines / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D006572:Heterocyclic Compounds, Bridged-Ring; D008024:Ligands; D009944:Organoplatinum Compounds; D011437:Propylamines; D010984:Platinum; D002945:Cisplatin