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Since the potential anticancer activity of auranofin was discovered, gold compounds have attracted interest with a view to developing anticancer agents that follow cytotoxic mechanisms other than cisplatin. Two benzimidazole gold(I) derivatives containing triphenylphosphine (Au(pben)(PPh3)) (1) or triethylphosphine (Au(pben)(PEt3)) (2) were prepared and characterized by standard techniques. X-ray crystal structures for 1 and 2 were solved. The cytotoxicity of 1 and 2 was tested in human neuroblastoma SH-SY5Y cells. Cells were incubated with compounds for 24 h with concentrations ranging from 10 &micro, M to 1 nM, and the half-maximal inhibitory concentration (IC50) was determined. 1 and 2 showed an IC50 of 2.7 and 1.6 &micro, M, respectively. In order to better understand the type of cell death induced by compounds, neuroblastoma cells were stained with Annexin-FITC and propidium iodide. The fluorescence analysis revealed that compounds were inducing apoptosis, however, pre-treatment with the caspase inhibitor Z-VAD did not reduce cell death. Analysis of compound effects on caspase-3 activity and reactive oxygen species (ROS) production in SH-SY5Y cells revealed an antiproliferative ability mediated through oxidative stress and both caspase-dependent and caspase-independent mechanisms.

The ligand 4bpytm [4bpytm = bis(4-pyridylthio)methane] in strongly acidic media afforded H24bpytm(NO3)2. The reaction of CuCl2.2H2O with 4bpytm at low pH values afforded three supramolecular compounds: H24bpytm[CuCl4] (1) and the monomeric complexes [CuCl3(H4bpytm)(4bpytm)] (2) and [CuCl2(H4bpytm)2]·Cl2 (3). Nevertheless, the same reaction using aprotic solvents under microwave irradiation afforded the 1D coordination polymers [CuCl2(4bpytm)]·2dmf (4.dmf) and [CuCl2(4bpytm)]·2dmso (4.dmso). The 3D supramolecular organization through weak interactions has been analyzed for all of the compounds, and their thermal behavior and structural dynamics after solvent release were also investigated for 4.dmf and 4.dmso. X-ray structural analysis of these complexes showed that the synthetic conditions used represent an effective method to obtain metal−organic square grid networks with cavities.

Reaction of the twisted pyridyl dithioether ligand bis(4-pyridylthio)methane (4bpytm) with silver(I) salts afforded four complexes with 1:1 stoichiometries, namely [Ag(4bpytm)](NO3) (1), [Ag(4bpytm)](ClO4) (2) and [Ag(4bpytm)](ClO4) ½CH2Cl2 ½dmf (2·Solv), [Ag(CH3COO)(4bpytm)]·H2O (3) and [Ag(CF3COO)(4bpytm)] (4). X-ray structural analysis of these complexes showed that one-dimensional structures are obtained for 1, 2·Solv and 4 whereas a two-dimensional network is formed in 3. The ligand 4bpytm acts as an N,N′-bis(monodentate) bridging system in all cases except in 3, where an unprecedented coordination mode is obtained with the ligand acting in a tridentate manner using its two pyridine nitrogen atoms and a sulfur atom. The coordination polymers are assembled through secondary contacts: Ag···Ag in 4, Ag···S in 1, 2·Solv and 4, Ag···O in 2·Solv, and hydrogen bonding interactions between crystallization water that join the polymeric layers in 3. All of these weak interactions link the low-dimensional complexes to give high-dimensional supramolecular structures and further stabilize the crystal structures in the solid state.

The 1D coordination polymer 1∞[Cu(HL)2(SS)]·4H2O (1) and the molecular compound [Cu2(HL)4(SCS)3] (2) [where SS = 4,4′-dipyridyldisulfide, SCS = bis(4-pyridylthio)methane and HL = lactate] have been prepared by reaction of the SS and SCS ligands with copper(II) lactate. X-ray structural analysis revealed that in 1 the SS ligand acts as an N,N′-bis(monodentate) system, whereas in 2 the SCS ligand acts in an N,N′-bis(monodentate) manner to produce a dinuclear compound and also as a monodentate terminal ligand. Hydrogen bonding interactions join the polymeric chains of 1 and the molecules of 2 to generate 3D networks. The thermal behaviour of the two compounds was investigated and the reversibility of the dehydration–rehydration processes in 1 was also evaluated.

The reaction of CuSO 4 · H 2 O with 4-bpytm [4-bpytm = bis(4-pyridylthio)methane] in EtOH afforded the complex [Cu(SO 4 )(4-bpytm)(H 2 O) 3 ] · H 2 O ( 1 · H 2 O ) while the reaction of 4-bpytm with Cu(NO 3 ) 2 · 3H 2 O in EtOH afforded the complex [Cu(NO 3 ) 2 (4-bpytm) 2 ] · H 2 O ( 2 · H 2 O). The reaction of 4-bpytm with Cu(NO 3 ) 2 · 3H 2 O in EtOH/dmf under microwave irradiation afforded the pseudo-polymorph [Cu(NO 3 ) 2 (4-bpytm) 2 ] · Solv ( 2 · Solv ). Compound 1 · H 2 O forms helical chains while compounds 2 · H 2 O and 2 · Solv are 2D coordination polymers with a (4,4) topology based on rhombic grids in 2 · H 2 O and on a parquet motif in 2 · Solv . The 3D supramolecular organization through hydrogen bonding is analyzed for the three compounds and their thermal behaviour was also investigated.

Reaction of SnPh3OH with 3-(2-hydroxyphenyl)sulfanylpropenoic acid [H2(o-hpspa)] yielded [SnPh3(SC)], where SC is deprotonated 3-sulfanylcoumarin (3-sulfanyl-2H-1-benzopyran-2-one, HSC), by a cyclization process. Similarly, when 3-(2-hydroxy-5-bromophenyl)- and 3-(2-hydroxy-3,5-dibromophenyl)-2-sulfanylpropenoic acids were treated with the same tin hydroxide, the cyclization resulted in [SnPh3(BrSC)] and [SnPh3(Br2SC)], where BrSC and Br2SC are the new ligands formed from the deprotonation of 3-sulfanyl-6-bromocoumarin and 3-sulfanyl-6,8-dibromocoumarin, respectively. The new compounds were characterized by elemental analysis, multinuclear NMR (1H, 13C and 119Sn) and vibrational spectroscopy, and mass spectrometry. Single-crystal X-ray structures of these complexes all showed that the tin atom is surrounded by three phenyl C atoms and the S and O atoms of the bidentate ligand in a distorted trigonal-bipyramidal environment. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)

The new ligand bis(4-pyridylthio)methane (4-bpytm) (1) and its complexes [CuX2(4-bpytm)] and [CuX2(4-bpytm)2] (X = Cl and Br) (2 – 5) have been prepared and characterized by elemental analysis, IR-Raman, UV/Vis spectroscopy. The structures of (4-bpytm) (1), [CuCl2(4-bpytm)2] (3) and [CuBr2(4-bpytm)2] (4) were determined by single-crystal X-ray diffraction analysis. X-ray analysis of the 1:2 derivatives reveals that the copper atom has a distorted (4 + 2) octahedral environment. The copper atom is coordinated by four nitrogen atoms from four bridging 4-bpytm ligands and two halogen atoms. The axial Cu–N bonds are considerably longer than the equatorial Cu–N bonds owing to JahnTeller distortion. CuX2 units are linked to each other through bridging 4-bpytm ligands to form a 2D interpenetrated coordination polymer. The structural parameters of the 4-bpytm ligand in these complexes were compared with those of the free ligand.

Two new mixed-ligand complexes [Fe(HG)2(dipyam)] (1) (HG = glycolato and dipyam = 2,2′-dipyridylamine) and [Cu(HB)2(im)2]·2H2O (2) (HB = benzilato and im = imidazole) have been hydrothermally synthesized and structurally characterised by X-ray diffraction. In both cases the metallic centre is in an octahedral environment, strongly distorted in 2 (4+2 coordination). The α-hydroxycarboxylato ligands (glycolato or benzilato) present different coordinative behaviour, bidentade chelate through the hydroxyl oxygen and one carboxy oxygen in 1 and through the two oxygen atoms of the carboxylate group in 2. The complexes are extended into 2D frameworks through hydrogen bonding and π···π or C-H···π interactions. The complexes were also characterized by elemental analysis, FT-IR and UV-vis spectroscopy and room temperature magnetic measurements.

Compounds of type [MX2(Hpben)] [M = Pd (X = Cl), Pt (X = Cl, I); Hpben = 2-(2′-pyridyl)benzimidazole] were prepared and characterized, and the structures of the Pt derivatives were determined by X-ray crystallography. The crystals of [PtI2(Hpben)] consist of discrete units in which the Pt atom is coordinated to two iodine atoms and to pyridine and imidazole N atoms in a distorted square planar arrangement. The structure of the chloro derivative is similar, except that the [PtCl2(Hpben)] monomers are hydrogen-bonded in zig-zag chains. In assays of the interactions of the Pd and Pt chloro compounds with DNA, and of their in vitro cytotoxic activity against human cervical carcinoma cells (HeLa-229), human ovarian carcinoma cells (A2780) and a cisplatin-resistant mutant A2780 line (A2780cis), the only activity observed was modest cytotoxicity of the Pd derivative for A2780. © 2005 Wiley-VCH Verlag GmbH & Co. KGaA.

Several new two-ligand complexes of zinc(II) with the aromatic N,N-donor ligands 2,2-bipyridine or 1,10-phenanthro- line and one of three different α-hydroxycarboxylates (HL) derived of the α-hydroxycarboxylic acids (H2L) (2-methyllactic, H2mL; mandelic, H2M or benzilic, H2B) were prepared. The compounds of formula (Zn(HL)2(NN))·nH2 O( HL HM, HB) were isolated as white powders and characterized by elemental analysis, IR spec- troscopy and thermogravimetric analysis. The complexes of general formula (Zn(HL)(NN)2)(HL)·nH2 O( HL HmL, HM) and (Zn(HB)2(NN)2), were obtained as single crystals and were charac- terized by elemental analysis, IR spectroscopy, thermogravimetric analysis and X-ray diffractometry. In all cases, the zinc atom is in

Dimeric complexes of composition [Re2X2(CO)6(HL)2] were obtained by reaction of fac-[ReX(CO)3(CH3CN)2] (X = Cl, Br) with 4-acetylpyridine thiosemicarbazone (HLH) and derivatives in which the thioamide nitrogen bore Me or Ph (HLMe and HLPh, respectively). In these complexes, which were characterized by X-ray crystallography and FAB, IR and 1H NMR spectroscopies, the thiosemicarbazone ligands bridge between two rhenium atoms by coordination of their Npyridine and S atoms. This coordination mode is unusual in that it does not involve any of the thiosemicarbazide nitrogen atoms. The isolation of dimeric complexes rather than monomers or polymers seems to have been due to their poor solubility and rapid precipitation from the reaction medium. [Re2Cl2(CO)6(HLH)2] (1a) was isolated in unsolvated form and as its acetone and acetonitrile solvates; [Re2Br2(CO)6(HLH)2] as its methanol solvate; and all the other complexes as acetone solvates. In all the solvated crystals except those of [Re2Cl2(CO)6(HLPh)2] (3a), all the solvent molecules are hydrogen-bonded to the complex, and in those of [Re2X2(CO)6(HLH)2] these hydrogen bonds contribute significantly to the cohesion of the structure (in particular, in [Re2Br2(CO)6(HLH)2]·2CH3OH there are no hydrogen bonds directly linking the dimers). In 3a·2(CH3)2CO the dimers are linked by N–H⋯π and C–H⋯O interactions, and the non-hydrogen-bonded solvent molecules occupy channels with interatomic long and short diameters of 8.5 and 5.6 A, respectively.

Nine mononuclear metal complexes of monoanionic α-hydroxycarboxylates (HL′) with imidazole as a co-ligand have been synthesised and structurally characterized by X-ray diffraction. The nickel(II) complexes can be described by two formulae: [Ni(HL′)2(Im)2], HL′=2-methyllactate (HmL) (1) or mandelate (HM) (2), and [Ni(HB)2(Im)3], HB=benzylate (3). In these compounds the nickel atom is in a distorted octahedral environment. The copper(II) complexes of the general formula [Cu(HL′)2(Im)], HL′=glycolate (HG) (4), lactate (HL) (5) or 2-methyllactate (HmL) (6) presents a square pyramidal coordination geometry with a distortion evaluated in terms of the τ parameter. The zinc(II) complexes have the general formula [Zn(HL′)2(Im)2] · xH2O, HL′=lactate (HL) and x=1/2 (7), 2-methyllactate (HmL) and x=0 (8) and display a distorted octahedral geometry. However, the reaction with H2B afforded the imidazole complex [Zn(Im)6](HB)2, HB=benzylate (9), which has two uncoordinated benzylate units. In most of the complexes the α-hydroxycarboxylato ligands behave as bidentate monoanionic systems, apart from in 3, where one ligand is monodentate. All of the complexes are extended into 2D or 3D frameworks through hydrogen bonding. The complexes were also characterized by elemental analysis, FT-IR and UV/Vis spectroscopy. The nickel and copper compounds were also studied by room temperature magnetic susceptibility and room temperature ESR spectra were obtained for the copper compounds. Finally, the thermal behaviour of all the compounds was investigated.

The reactions of methylacetoacetate and ethyl 2-methylacetoacetate thiosemicarbazones (H(2)L(A) and H(2)L(B), respectively) with [ReX(CO)(5)] and [ReX(CO)(3)(CH(3)CN)(2)] (X = Cl, Br) were explored under various experimental conditions. Besides the adducts fac-[ReX(CO)(3)(H(2)L)], in which the rhenium is coordinated to three carbonyl groups, the X anion, and the N,S-bidentate thiosemicarbazone ligand, the following complexes were also isolated: fac-[ReBr(CO)(3)(Hpyz(B))], the tetrameric complexes fac-[Re(pyz(A))(CO)(3)](4) and fac-[Re(pyz(B))(CO)(3)](4), and fac-[Re(pyz(B))(CO)(3)(H(2)O)] (where Hpyz(A) and Hpyz(B) are pyrazolones derived by cyclization of H(2)L(A) and H(2)L(B), respectively). The cyclization reactions were monitored by (1)H NMR spectroscopy and the complexes isolated were identified by elemental analysis, mass spectrometry, IR and (1)H NMR spectroscopy, and in some cases by X-ray diffractometry. The isolation and the full structural identification of the rather unusual fac-[ReBr(CO)(3)(Hpyz(B))], which contains the enol form of the pyrazolone ligand, affords new insight into the cyclization of thiosemicarbazones derived from beta-keto esters.

The complexes [Cd2Cl4(bpytm)] (1), [CdBr2(bpytm)] (2), [Cd2Br4(bpytm)] (3) and [CdI2(bpytm)] (4) [bpytm = bis(2-pyridylthio)methane] were prepared and characterized by elemental chemical analysis, by IR, Raman and 1H and 13C NMR spectroscopy, and in the cases of 2 and 4 by X-ray diffractometry. In 2 and 4 the ligand is N,N′-bidentate, forming an eight-membered chelate ring. © 2003 Elsevier Science Ltd. All rights reserved.

The mononuclear complexes [M(HmL)2(H2O)2], where M=Mn(II) (1), Ni(II) (2) or Zn(II) (3) and HmL=2-methyllactato, were prepared and characterized by elemental analysis, FT-IR and UV/Vis spectroscopy and room temperature magnetic susceptibility measurements. Their thermal behaviour was also investigated, and compounds 1 and 3 were characterized by X-ray diffractometry. In both cases, the metal ion is hexacoordinated to two (O,O′)-bidentate monoanionic 2-methyllactato ligands and two aqua ligands in a distorted octahedral fashion. The [M(HmL)2(H2O)2] units are connected by hydrogen bonds, forming a two-dimensional network.

The mononuclear compounds [Cu(OAc)(bipy)2]Cl·4H2O·1/2MeOH(1) and [Co(OH2)2(phen)2](OAc)2·6H2O(2) were unexpectedly obtained as single crystals from mother liquors left following isolation of the expected products of the reactions, in ethanol of Cu(OAc)2, benzylic acid and 2, 2'-bipyridine (for 1) and Co(OAc)2, D, L-mandelic acid and 1, 10-phenanthroline (for 2). The complexes were characterized by elemental analysis, IR and electronic spectroscopy and magnetic measurements at room temperature and their structures were determined by single-crystal X-ray analysis. In 1, the pentacoordinated copper atom has a basically square pyramidal coordination polyhedron, while in 2 the cobalt atom has a distorted octahedral environment. In both cases, the complexes are linked by hydrogen bonds and aromatic-aromatic interactions. Unerwartete Bildung der Gemischtligand-Komplexe [Cu(OAc)(bipy)2]Cl·4H2O-·1/2MeOH und [Co(OH2)2(phen)2](OAc)2·6H2O und ihre Kristallstrukturen Die einkernigen Verbindungen [Cu(OAc)(bipy)2]Cl·4H2O·1/2MeOH (1) und [Co(OH2)2(phen)2](OAc)2·6H2O (2) wurden unerwartert als Einkristalle aus Mutterlaugen der erwarteten Produkte der Reaktion von Cu(OAc)2, Benzylsaure und 2, 2′-Bipyridin (fur 1) und Co(OAc)2, D, L-Mandelsaure und 1, 10-Phenanthrolin (fur 2) in Ethanol erhalten. Die Komplexe werden durch Elementaranalysen, IR- und Elektronenspektren und durch magnetische Messungen bei Raumtemperatur sowie durch Einkristallstrukturanalysen charakterisiert. In 1 bildet das funffach koordinierte Kupferatom ein tetragonal-pyramidales Koordinationspolyeder, wahrend in 2 das Cobaltatom verzerrt oktaedrische Umgebung hat. In beiden Fallen sind die Komplexe uber Wasserstoffbruckenbindungen und Aromaten-Aromaten-Wechselwirkungen verknupft.

The reactions of [ReBr(CO) 5 ] with ferrocenylcarbaldehyde thiosemicarbazones HL with different groups attached to the amide nitrogen (R=H, Me, Ph) yielded complexes [ReBr(CO) 3 (HL)] ( 1 ) in which, according to X-ray studies of 1a ·{(CH 3 ) 2 CO} and 1b ·1/2{CH 2 Cl 2 }, the thiosemicarbazone is N , S -bidentate and the geometry around the metal fac -octahedral. Compounds of formula [ReL(CO) 3 ] 2 ( 2 ) were then prepared by reaction of the corresponding adduct 1 with NaOMe in acetone. A complex of formula [ReL 2 (CO) 3 ] 2 ( 2b ′) was also obtained as a dissolvate by slow concentration of a solution of 1b in acetone. Single crystals of 2a and 2b obtained from the mother liquors are composed of centrosymmetric dimers formed by ReSRe bridges, where S is the thiolic sulfur of an N , S -bidentate thiosemicarbazonato ligand. Although 2b ·2{(CH 3 ) 2 CO} and 2b ′·2{(CH 3 ) 2 CO} have similar co-ordination spheres, they differ as regards the configuration of the thiosemicarbazonato ligand about the azomethine bond and certain bond lengths (notably ReN); it seems likely that the configuration of L 2− determines how close the rhenium can approach the N atom of the ligand, and hence the delocalization of the π electrons in the CNN fragment of the thiosemicarbazide chain. The mass, IR and UV–vis spectra of the complexes, and their electrochemical behavior, are also discussed.

Compounds in which N-phenylpiperazines were linked by a propyloxy chain to position 6 or 7 of a coumarin ring were designed and synthesised, and their affinities for 5-HT(1A) and D(2A) receptors were determined by radioligand binding assays. The influence of para substitution in the phenyl ring, substitution at position 4 of the coumarin system, and the coumarin position at which the piperazinylalkyl chain is linked was explored. Electron-withdrawing phenyl ring substituents para to the piperazine strongly reduced activity at both receptors. Binding at 5HT(1A) was influenced by the bulk of substituents at position 4 of the coumarin system, and binding at D(2A) by their electronic properties. Neither binding affinity was significantly affected by whether the piperazinylalkyl chain was inserted at position 6 or 7 of the coumarin system.

The reaction of the flexible pyridyl dithioether ligand Bis(4-pyridylthio)methane (4-bpytm) with copper(II) formiate led to the formation of the coordination polymer [Cu(HCOO)2(4-bpytm)] n, which has been characterized structurally. The copper atom is in a square-planar environment and 4-bpytm acts as an HN′-bis(monodentate) bridging ligand creating an one-dimensional polymeric arrangement. The formiate ligand plays a key role in the supramolecular organization of the chains via CHformiate...Oformiate and CH4bpytm...O formiate hydrogen bonds. © 2007 WILEY-VCH Verlag GmbH & Co. KGaA.

We report herein a novel infinite two-dimensional water morphology, found in a metallo-organic host, made up of discrete cyclic water hexamers and which contains large circular holes defined by 18 molecules of water.

The title compound was prepared from 1-methyl-2(3H)-inidazolinethione and triphenyltin(IV) hydroxide, and its crystal structure was determined by X-ray diffraction. The crystal consists of discrete molecules with the tin atom coordinated to one carbon atom of each of the three phenyl groups and to the sulfur atom of the deprotonated ligand. An SnN interaction [2.920(3) A] slightly distorts the tin coordination geometry from that of a perfect tetrahedron. NMR spectroscopy was used to study the hydrolysis of this compound in CDC13.

[SnPh2(Hmimt)4](NO3)2 [Hmimt = 1-methyl-2(3H)-imidazolinethione] was synthesized and characterized by IR, Raman, Mossbauer and 1H, 13C and 119Sn NMR spectroscopy. The crystal structure of its dihydrate, consisting of [SnPh2(Hmimt)4]2+ cations, nitrate anions and water of crystallization, was determined by X-ray diffraction: in the cation the tin atom is coordinated to a carbon atom of each of the phenyl groups and to the S atoms of four Hmimt ligands in a distorted octahedral arrangement. This structure is compared with those of the corresponding SnMe22+ and SnEt22+ complexes.

Three ionic complexes, [Ag(Hmimt)](NO3), [Ag(Hmimt)2](NO3) and [Ag(Hmimt)3(NO3) (Hmimt = 1-methyl-2(3H)-imidazolinethione), were synthesized by reacting AgNO3 with Hmimt and characterized spectroscopically (mass, IR and 1H, 13C, 15N and 109Ag NMR). The structure of [Ag(Hmimt)3](NO3) was determined by X-ray crystallography. In this compound, which crystallizes in the monoclinic system (space group P21/n; a = 7.621(2), b = 27.281(5), c = 10.256(4) A, β = 107.89(1)°, Z = 4) the Ag+ ion is trigonally coordinated in the [Ag(Hmimt)3]+ cation, with a mean Ag⋯S distance of 2.489 A. The shortest Ag3.O distance is 2.929 A, and the crystal lattice features an extensive network of hydrogen bonds.

Complexes [Re2(μ-X)2(CO)6(NCCH3)2] (X = Cl, Br) have been easily prepared in high yield by refluxing of fac- [ReX(CO)3(NCCH3)2] in toluene. The crystal and molecular structure of the bromine derivative have been determined by X-ray analysis. The molecule consists of two fac-Re(CO)3 fragments bridged by two bromine atoms. The acetonitrile molecules reside above and below the Re2Br2 plane.

The title neutral complex, [Co(HG)2(H2O)2] or [Co(C2H3O3)2(H2O)2], contains monoanionic O,O′-bidentate glycolate ligands that chelate the cobalt(II) ion through the carboxyl­ate and hydroxyl O atoms to form five-membered chelate rings. The configuration around the cobalt ion can be described as all-cis. The nature of the ligands permits the formation of a supramolecular architecture based on hydrogen bonding.

The structure of [Co2(μ-OH)2(μ-OAc)(OAc)2(dipyam)2]AcO · EtOH (1) has been determined by single-crystal X-ray analysis. The cationic complex may be described as a “di(μ-hydroxo)(μ-acetato)dicobalt(III)” core with chelating 2, 2′-dipyridylamine and monodentate acetate ligands. The coordination polyhedron around each cobalt atom is a distorted octahedral. The dimers are linked in the crystal by N-H···Oionic AcO and C-H···Omonodentate AcO hydrogen bonds. Spectroscopic data are also presented.

The title compound, C6H9N3OS, was obtained by cyclization of ethyl 2-methyl­aceto­acetate thio­semicarbazone with sodium methanolate in methanol. Single crystals suitable for X-ray analysis were obtained by slow evaporation of the mother liquor. The pyrazolone moiety is essentially planar. The S atom is cis with respect to the protonated endocyclic N2 atom, probably because the intramolecular hydrogen bonds allowed by this arrangement afford greater stability than those allowed when S is trans to N-2. Intermolecular hydrogen bonds link the mol­ecules in interlocking pleated sheets, stacked along the c axis.

The structure of the title compound, [Co(AcO)2(2,2′-bipy)(H2O)2] or [Co(C2H3O2)2(C10H8N2)(H2O)2], consists of mononuclear mol­ecules with crystallographic twofold rotation symmetry. The Co atom displays a distorted tetragonally compressed octahedral environment, with a unique Co—N distance of 2.1227 (14) A and Co—O distances in the range 2.0976 (13)–2.1256 (14) A. The mol­ecules are self-assembled via hydrogen bonds to form an one-dimensional chain and via aromatic–aromatic interactions giving a two-dimensional structure.

Compounds in which N-phenylpiperazines were linked by a propyloxy chain to position 6 or 7 of a coumarin ring were designed and synthesised, and their affinities for 5-HT(1A) and D(2A) receptors were determined by radioligand binding assays. The influence of para substitution in the phenyl ring, substitution at position 4 of the coumarin system, and the coumarin position at which the piperazinylalkyl chain is linked was explored. Electron-withdrawing phenyl ring substituents para to the piperazine strongly reduced activity at both receptors. Binding at 5HT(1A) was influenced by the bulk of substituents at position 4 of the coumarin system, and binding at D(2A) by their electronic properties. Neither binding affinity was significantly affected by whether the piperazinylalkyl chain was inserted at position 6 or 7 of the coumarin system.

The crystal structures of the [TlMe2L] and [SnMe2L2](L = pyridine-2-thiolate) have been determined. Dimethyl(pyridine-2-thiolato)thallium(III) crystallizes in the monoclinic space group P21/n(no 14) with a= 8.169(1), b= 13.214(1), c= 8.876(2)A, β= 104.61 (1)°, and Z= 4. Refinement converged to R= 0.047 for 1 531 independent observed reflections. The thallium atom co-ordinates to the two methyl carbons [Tl–C 2.159(8) and 2.199(8)A], to the pyridine nitrogen [Tl–N 2.494(7)A], and to two sulphur atoms [Tl–S 3.160(3) and 2.870(2)A]. Dimethylbis(pyridine-2-thiolato)tin(IV) crystallizes in the monoclinic space group P21/m(no 11) with a= 6.664(5), b= 17.342(5), c= 6.943(3)A, β= 112.53(5)°, and Z= 2. Refinement converged to R= 0.038 for 1 105 independent observed reflections. The tin atom co-ordinates to the two methyl carbons [Sn–C 2.133(9)A], the two pyridine nitrogens [Sn–N 2.702(5)A], and the two sulphur atoms [Sn–S 2.487(2)A]. The structural characteristics of the free ligand are compared with those of the co-ordination compounds, and the mass and 13C n.m.r. spectra of the two complexes are compared.

The title compound, C12H8N2.C20H14O2, was obtained as a 1:1 adduct from non-aqueous solutions of the two components. The lattice contains centrosymmetric dimers in which O—H⋯O and O—H⋯N hydrogen bonding is important. Rotation about the C—C′ bond of the binaphthyl moiety produces a torsion angle of −85.5 (2)°.

The reaction of [ReX(CO)5] with thiosemicarbazones H2L(R) derived from beta-keto esters (X = Cl, Br; R = Me, Ph) allowed the isolation of cyclic trimeric complexes [Re3(pyz(R))3(CO)9], where pyz(R) is the pyrazolonate corresponding to the thiosemicarbazone. Electron spray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI-FTICR-MS) monitoring of the reactions of H2L(Ph) in toluene confirmed that the trimer was formed in the reaction mixture and no higher oligomer was detected. These studies, together with the X-ray structures of the trimeric complexes, afford new insight into the factors influencing the self-assembly of pyrazolonaterhenium(I) complexes.

The title compound, [SnCl(2)(CH(3))(C(6)H(5))(C(5)H(8)N(2))(2)], was obtained by reaction of dichloromethylphenyltin(IV) and 3, 5-dimethylpyrazole (dmpz) in chloroform, and was recrystallized from acetone. The structure consists of octahedral all-trans [SnMePhCl(2)(dmpz)(2)] molecules, with the Sn atom coordinated to two C [Sn-C 2.127 (5) and 2.135 (4) A], two Cl [Sn-Cl 2.5753 (8) A] and two N atoms [Sn-N 2.357 (3) A]. The dmpz ligands, bound to the metal through their unprotonated N atoms, form weak intra- and intermolecular hydrogen bonds with the Cl ligands via their NH groups, giving rise to a polymeric chain along the c axis.

A cobalt(II) complex of methyllactato and 1,10-phenanthroline 1 [Co(HmL)(1,10-phen)2](HmL)·4H2O (HmL = 2-methyllactato) was synthesized and its crystal structure was determined by single-crystal X-ray diffractometry. This compound crystallizes in triclinic space group P-1, with a = 9.0194(15), b = 13.406(2), c = 13.977(2)A, α = 94.969(4), β = 99.878(3), γ = 91.351(3)°, V = 1657.4(4)A3 and Z = 2. The cobalt(II) ion is six-coordinated in a distorted octahedral environment.

Compounds [Cu(en)2(OH2)2](HB)2· 2H2O (1) and [Cu(HB)(en)2(OH2)](HB) (2) (HB = benzilate; en = ethylenediamine) present the Cu(II) atom coordinated by different N4O2 donor sets, with 4 + 2 and 4 + 1 + 1 coordination geometries, respectively. In compound 1 the Cu(II) atom is located on a centre of inversion. Copyright © 2005 John Wiley & Sons, Ltd.

The structure of [Zn(HB)2(1,10-phen)2] (HB = diphenylglycolato) comprises mononuclear molecules with the zinc(II) cation situated on a two fold axis and octahedrally coordinated by an N4O2 donor set. Copyright © 2004 John Wiley & Sons, Ltd.

The yellow-orange crystals of [Pt(Hmimt)4](NO3)2 [Hmimt = 1-methyl-2(3H)-imidazolinethione] are monoclinic [P21, a = 8.136(3), b = 13.978(4), c = 12.150(9)A, β = 96.89(5)°]. They consist of [Pt(Hmimt)4]2+ cations and nitrate anions. In the cation the Pt atom is coordinated by four S atoms [Pt-S: 2.291(5)-2.357(5)A] in a slightly distorted square planar arrangement.

The versatile coordination chemistry of bis(pyrimidin-2-ylthio)methane (bptm) allows the synthesis of a series of different metal complexes with diverse structures. We describe here the synthesis and structural characterization of three kinds of compounds: four cyclic dimers, [Co(2)Cl(4)(bptm)(2)] (1), [Zn(2)I(4)(bptm)(2)] (2), [Cd(2)I(4)(bptm)(2)] (3), [Cu(2)(NO(3))(4)(bptm)(2)] (4); two acyclic dimers, [Cu(2)Br(4)(bptm)(3)] (5), [Cu(2)(AcO)(4)(bptm)(2)] (6); and two 2D coordination polymers, [CuBr(bptm)] (7) and [CuI(bptm)] (8). Different structural models are obtained on making small changes in the building units under different synthetic conditions. The effects of the weak interactions in the crystal packing were also analyzed.

The compound [2bpytmH](2)[I(3)](2)[I(2)], which contains protonated 2bpytm, and four neutral monomeric complexes [CoCl(2)(2bpytm)]·H(2)O (1), [CoBr(2)(2bpytm)] (2), [CoI(2)(2bpytm)]·1/2H(2)O (3) and [NiBr(2)(2bpytm)]·H(2)O (4) have been obtained during a study into the reactivity of the bis(2-pyridylthio)methane (2bpytm) ligand towards cobalt(II) and nickel(II) halides. Furthermore, a cyclic dimer [CuBr(2)(2bpytm)](2) (5) and a 1D polymer [CuBr(2)(2bpytm)](n)·CH(3)CN (6) have been obtained from copper(II)/(I) bromide salts. An unprecedented S-CH(2)-S activation and cleavage in 2bpytm has been observed on using copper(II) salts with organic and voluminous inorganic anions. The cleavage of 2bpytm enabled the isolation of copper(II) complexes containing the in situ generated ligands 2-pyridinethiolate, 2-pyridinesulfenate or 2-pyridinesulfonate.

In the title complex, [Sn(C2H5)2Cl2(C5H5N)2], the Sn atom lies on an inversion centre and is octahedrally coordinated by two Cl atoms, two ethyl C atoms and two pyridine N atoms in an all-trans configuration. The dihedral angle between the pyridine ring and the SnNCl plane is 22.4 (2)°.

The following molecular complexes of transition metals MII with lactato (HL) and 1,10-phenanthroline (phen) ligands were prepared and characterized structurally: [M(HL)2(phen)]·nH2O, MII = Mn, Co, Ni, Cu, Zn; 1–6), [M(HL)(H2O)2(phen)]Cl, (MII = Mn, Co, Ni; 7–9), and [Ni(HL)(H2O)2(phen)]Br (10). These neutral and cationic octahedral complexes have 3-D supramolecular architectures due to weak noncovalent interactions. In the halide compounds, C–H⋯X− hydrogen bonds play a key role in the stabilization of the 3-D network.

Bis(2-pyridylthio)methane [bpytm, (pyS)2CH2] and complexes of this ligand with ZnII, HgII, CuI, and AgI have been prepared and characterised by elemental analysis, by IR, Raman and 1H and 13C NMR spectroscopy, and by X-ray diffractometry. The ligand is N, N′-didentate in the ZnII complexes; N-monodentate in one HgII complex and N, N′-bis(monodentate) in the other; N-mono-N′, S-didentate in the CuI complex; and N, S′-bis(mono)-N′, S-didentate in the AgI complex. The structural parameters of the ligand in each coordination mode are compared with those of the free ligand and those of the triiodide salt of the protonated ligand. Komplexchemie des vielseitigen Liganden Bis(2-pyridylthio)methan Bis(2-pyridylthio)methan, [bpytm, (pyS)2CH2], und Komplexe dieses Liganden mit ZnII, HgII, CuII und AgI wurden dargestellt und durch Elementarananalyse, IR-, Raman- sowie 1H- und 13C-NMR und Rontgenstrukturanalyse charakterisiert. Der Ligand ist N, N′-zweizahnig in den ZnII-Komplexen, N-einzahnig in einem und N, N′-bis(einzahnig) in den anderen HgII-Komplexen, N-mono-N′, S-zweizahnig im CuI-Komplex und N, S′-bis(mono)-N′, S-zweizahnig im AgI-Komplex. Die Strukturparameter des Liganden in jeder Koordinationsform werden mit denen des freien Liganden und denen des Triiodids des protonierten Liganden verglichen.