Metal-(Acyclic Diaminocarbene) Complexes Demonstrate Nanomolar Antiproliferative Activity against Triple-Negative Breast Cancer.

Invited for the cover of this issue are Tatiyana Serebryanskaya, Mikhail Kinzhalov and co-workers at St. Petersburg State University, the Research Institute for Physical Chemical Problems, Belarusian State University, Togliatti State University and Blokhin National Medical Research Center of Oncology. The image depicts the shield of Pallas Athena with the structure of a palladium carbene complex that protects against triple-negative breast cancer.

Metal-(Acyclic Diaminocarbene) Complexes Demonstrate Nanomolar Antiproliferative Activity against Triple-Negative Breast Cancer.

Hydrolytically stable Pd and Pt complexes supported by acyclic diaminocarbene ligands represent a novel class of structural organometallic anticancer agents exhibiting nanomolar antiproliferative activity in a panel of cancer cell lines (IC 0.07-0.81 μM) and up to 300-fold selectivity for cancer cells over normal primary fibroblasts.

Palladium(II)-Stabilized Pyridine-2-Diazotates: Synthesis, Structural Characterization, and Cytotoxicity Studies.

Well-defined diazotates are scarce. Here we report the synthesis of unprecedented homoleptic palladium(II) diazotate complexes. The palladium(II)-mediated nitrosylation of 2-aminopyridines with NaNO results in the formation of metal-stabilized diazotates, which were found to be cytotoxic to human ovarian cancer cells.

Identification and H(D)-bond energies of C-H(D)Cl interactions in chloride-haloalkane clusters: a combined X-ray crystallographic, spectroscopic, and theoretical study.

The cationic (1,3,5-triazapentadiene)Pt(II) complex [Pt{NH[double bond, length as m-dash]C(N(CH2)5)N(Ph)C(NH2)[double bond, length as m-dash]NPh}2]Cl2 ([]Cl2) was crystallized from four haloalkane solvents giving [][Cl2(CDCl3)4], [][Cl2(CHBr3)4], [][Cl2(CH2Cl2)2], and [][Cl2(C2H4Cl2)2] solvates that were studied by X-ray diffraction. In the crystal structures of [][Cl2(CDCl3)4] and [][Cl2(CHBr3)4], the Cl(-) ion interacts with two haloform molecules via C-DCl(-) and C-HCl(-) contacts, thus forming the negatively charged isostructural clusters [Cl(CDCl3)2](-) and [Cl(CHBr3)2](-). In the structures of [][Cl2(CH2Cl2)2] and [][Cl2(C2H4Cl2)2], cations [](2+) are linked to a 3D-network by a system of H-bondings including one formed by each Cl(-) ion with CH2Cl2 or C2H4Cl2 molecules.

Coupling of platinated triguanides with platinum-activated nitriles as a novel strategy for generation of dimetallic systems.

One of two Pt(IV)-activated propanenitriles in trans-[PtCl4(EtCN)2] is involved in platinum(IV)-mediated nitrile-imine coupling with the platinum(II)-based metallacycles [PtCl2{NH=C(NR2)N(Ph)C(=NH)N(Ph)C(NR2)=NH}] [R2 = Me2 (1a), C5H10 (1b)] yielding diplatinum products, whose structures depend on molar ratios between the reactants. At a 1 : 1 ratio, the mixed-valence platinum(II)/platinum(IV) species [PtCl4{NH=C(NR2)N(Ph)C{=[(N(Et)C=NH)PtCl2(EtCN)]}N(Ph)C(NR2)=NH}] [R2 = Me2 (2a), (CH2)5 (2b)] were generated, whereas at a 1 : 2 ratio the dinuclear platinum(II)/platinum(II) complexes [PtCl2{NH=C(NR2)N(Ph)C{=[(N(Et)C=NH)PtCl2(EtCN)]}N(Ph)C(NR2)=NH}] [R2 = Me2 (3a), (CH2)5 (3b)] were obtained. In contrast to the nitrile-imine coupling observed for the platinum(IV) dinitrile complex, the reaction between the platinum(II) congener trans-[PtCl2(EtCN)2] and any one of 1a,b gives exclusively the substituted dimetallic platinum(II)/platinum(II) products [PtCl2{NH=C(NR2)N(Ph)C{=[(NH)PtCl2(EtCN)]}N(Ph)C(NR2)=NH}] [R2 = Me2 (6a), (CH2)5 (6b)] featuring platinum-containing guanidine 1 as one of the ligands.

Gold(I) thiotetrazolates as thioredoxin reductase inhibitors and antiproliferative agents.

Gold(i) complexes with phosphane and thiotetrazolate ligands were prepared and investigated as a new type of bioactive gold metallodrugs. The complexes triggered very efficient inhibition of the enzyme thioredoxin reductase (TrxR), which is an important molecular target for gold species. Strong cytotoxic effects were observed in MDA-MB-231 breast adenocarcinoma and HT-29 colon carcinoma cells, and the complexes also caused strong effects in vincristine resistant Nalm-6 leukemia cells.

Synthesis, characterization, and biological evaluation of new tetrazole-based platinum(II) and palladium(II) chlorido complexes--potent cisplatin analogues and their trans isomers.

Two series of tetrazole-containing platinum(II) and palladium(II) chlorido complexes, trans-[ML(2)Cl(2)] (M=Pt, Pd) and cis-[PtL(2)Cl(2)]·nH(2)O (n=0, 1), where L is 1- or 2-substituted 5-aminotetrazole, have been synthesized and thoroughly characterized. Configuration of platinum(II) complexes obtained from the reaction of 5-aminotetrazoles with K(2)PtCl(4) has been found to vary depending on the nature of tetrazole derivatives and reaction conditions. According to in vitro cytotoxic evaluation, only platinum complexes display noticeable antiproliferative effect, and their cytotoxicity depends strongly on their geometry and hydrophobicity of the carrier ligands.

catena-Poly[[bis-[1-(2-hydroxy-ethyl)-1H-tetra-zole-κN]copper(II)]-di-μ-chlorido]: a powder study.

The crystal structure of the title polymeric complex, [CuCl(2)(C(3)H(6)N(4)O)(2)](n), was obtained by the Rietveld refinement from laboratory X-ray powder diffraction data collected at room temperature. The unique Cu(II) ion lies on an inversion center and is in a slightly distorted octa-hedral coordination environment. In the hydroxy-ethyl group, all H atoms, the O atom and its attached C atom are disordered over two positions; the site occupancy factors are ca 0.

Bis(1-methyl-1H-tetrazol-5-yl)diazene and two its copper(I) chloride complexes poly[[[mu-1,2-bis(1-methyl-1H-tetrazol-5-yl)diazene-kappa4N',N4:N,N4']dicopper(I)]-di-mu-chloro] and catena-poly[[chlorocopper(I)]-mu-1,2-bis(1-methyl-1H-tetrazol-5-yl)diazene-kappa4N',N4:N,N4'].

While bis(1-methyl-1H-tetrazol-5-yl)diazene, C4H6N10, (I), has no crystallographically imposed symmetry, in the two title chlorocopper(I) complexes, [Cu2Cl2(C4H6N10)]n, (II), and [CuCl(C4H6N10)]n, (III), the organic ligands lie across centres of inversion; in (III), the Cu and Cl atoms additionally lie about a twofold rotation axis in the space group P2/c. Complex (II) forms a two-dimensional coordination polymer containing tetrahedrally coordinated Cu(I) atoms, and complex (III) forms a one-dimensional coordination polymer containing five-coordinate square-pyramidal Cu(I) atoms.