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This review focuses on the synthetic inorganic chemistry of structural and functional models of Mo-Cu CO dehydrogenase (CODH). Mo-Cu CODH is an aerobic enzyme that catalyzes CO oxidation. The active site of Mo-Cu CODH demonstrates a structural motif unprecedented in inorganic chemistry: dithiolene-ligated MoVIO2S linked to a two-coordinate Cu(I) through a single bridging sulfido, {MoVIO2(μ2-S)CuI}. There is significant interest in understanding how this unusual active site structure enables reactivity. Structural analogues of varying accuracy have been reported by several research groups and are discussed in this review. Most of the modeling chemistry indicates that the single sulfido-bridged MoVI-(μ2-S)-CuI structure is unstable when the metals are coordinatively unsaturated, generally collapsing into the stable MoVI-(μ2-S)2-CuI or MoVI-(μ2-S)(μ2-O)-CuI diamond cores outside of the protein environments. Whereas singly bridged {MoVIO2(μ2-S)CuI} oxidizes CO and inserts CNR (isocyanide) efficiently, no biomimetic CODH-relevant reactivity was observed for the synthetic analogues containing the aforementioned diamond cores. An alternative synthetic approach pursuing a "bioinspired" functional model is also discussed. In this approach, two relevant metal sites (hypothesized to be primarily responsible for the reactivity) are combined into a heterobimetallic complex using appropriate heterodinucleating ligands. Syntheses, structures, and cooperative bimetallic reactivity of these heterobimetallic complexes will be discussed. [ABSTRACT FROM AUTHOR]

[M2L3]-type metallo-supramolecular architectures (MSAs) are widely explored for their biological activity, whereas data on non-symmetric, heterobimetallic [MM'L3] structures is comparatively rare. [M2L3] compounds are known to form helicates and/or mesocates. Here, we report the self-assembly of a discrete non-symmetrical, heterobimetallic MSA by combination of an amine-functionalised cobalt(III)-tris((picolinamido)ethyl)amine (PICTREN) base unit with FeCl2 and 2,2'-bipyridine-5-carboxaldehyde. NMR spectroscopy in tandem with computational studies revealed the formation of a mesocate rather than a helicate. The ability of the heteromesocate to bind to DNA was examined by gel electrophoresis with pUC19 plasmid DNA, which showed DNA binding although longer incubation periods were required than found for a known DNA-interacting helicate. The mesocate displayed promising antiproliferative activity in cancer cells, including a cisplatin-resistant cell line, with IC50 values in the 17–26 μM range. Lower biological activity of the mesocate compared to a metallocylinder reference and cisplatin may be explained by differences in the DNA interactions. This work further supports efforts to establish methods with which to construct heterobimetallic complexes, establishing the utility of the self-assembly method in [M2L3]-type assemblies using the cobalt(III)-PICTREN platform as a robust building block towards more complex assemblies of the [MM'L]-type. [ABSTRACT FROM AUTHOR]

A heterobimetallic 3d–4f complex [Cu(L)Dy(NO3)3] based on a symmetric salamo-like ligand (H2L) was synthesized and characterized by elemental analyses, IR, UV-Vis spectroscopy, and single-crystal X-ray diffraction. The complex crystallized in the monoclinic, space group P 21/c, included one tetra-coordinated Cu(II) atom (Cu1), one deca-coordinated Dy(III) atom (Dy1), one completely deprotonated (L)2− unit, and three nitrate groups involved in coordination. Cu1 adopted a planar quadrilateral configuration, and Dy1 formed a slightly distorted double-cap square antiprism geometry. The complex finally formed an infinite 2D and 3D supramolecular structure via the intermolecular hydrogen bonds and π–π interactions. Due to the paramagnetism of Cu2+ ions, the complex showed fluorescence quenching. The electronic structure and stability of the complex were proved by density functional theory (DFT) calculation. [ABSTRACT FROM AUTHOR]

In this tutorial, we describe the applications of well-defined heterobimetallic complexes in coordination insertion polymerization catalysis. The presence of two different metals in a single catalyst platform imparts reactivity patterns that are distinct from those of their homobimetallic and monometallic counterparts. We will demonstrate that heterobimetallic complexes are a versatile and unique class of catalysts by providing representative examples from recent studies of carbon dioxide/epoxide, lactone, lactide, and olefin polymerization. We will focus on the various strategies employed to synthesize mixed metal species, methods to characterize their structures, and the mechanistic roles of the metal ions during polymerization. [ABSTRACT FROM AUTHOR]

Two new ferrocenyl iminopyridyl ligands, L1 and L2, have been synthesized and characterized using spectroscopic and analytical techniques. Both ligands were used to prepare new Rh(I) and Ru(II) ferrocenyl complexes 1-4. The structures of the complexes were confirmed using 1H and 13C nuclear magnetic resonance spectroscopy, high resolution electrospray ionization mass spectrometry, and infrared spectroscopy. The complexes were tested as catalysts in the hydroformylation of 1-octene. Rh ferrocenyl complexes 1 and 4 produced aldehydes under mild conditions while the Ru-ferrocenyl complexes 2 and 3 required higher temperature and pressure for effective hydroformylation to occur. The catalysts display excellent aldehyde chemoselectivity with varying regeoselectivity depending on temperature and pressure conditions employed. At high temperatures, the Rh ferrocenyl precatalysts favor formation of branched aldehydes due to increased isomerization at high temperatures. The Ru ferrocenyl precatalysts displayed less hydroformylation activity; however, the complexes show good chemoselectivity for aldehydes with no hydrogenation products formed. [ABSTRACT FROM AUTHOR]

Bimetallic chlorodi-/triorganotin(IV) derivatives of general formulas R2(H2O)SnLCSSSn(Cl)R2 (R=Me: 1; Ph: 2) and R3Sn(Na)LCSSSnR3·H2O (R=Bu: 3; Ph: 4) were prepared by reaction of iminodiacetic acid disodium salt hydrate (Na2LH) with CS2 and R2SnCl2/R3SnCl in methanol. The reaction between Na2LH, CS2, and PdCl2 produced [Na2LCSS]2Pd·2H2O (5) which was treated with R3SnCl to synthesize the heterobimetallic derivatives [R3Sn(Na)LCSS]2Pd·2H2O (R=Me: 6; Ph: 7). The complexes were characterized by microanalysis, spectroscopic, and thermogravimetric analyses. Elemental analysis data, mass fragmentation, and thermal degradation patterns supported the molecular composition of the complexes. FT-IR data indicated monodentate binding of carboxylate while a chelating coordination mode of the dithiocarboxylate was verified in the solid state. A five-coordinate tin(IV) was demonstrated in the solid state. In solution, a tetrahedral/trigonal bipyramidal configuration around Sn(IV) and a square planar geometry of Pd(II) was indicated by multinuclear NMR (1H and 13C) and UV-visible studies. The Pd(II) derivatives showed interaction with salmon sperm-DNA and caused an inhibition of alkaline phosphatase (ALPs). The antibacterial/antifungal potential of the coordination products varied with the nature of incorporated metal and a substitution pattern at tin(IV); the palladium metallation decreased the antimicrobial activities. The triorganotin(IV) products exhibited more powerful action against bacteria/fungi as compared to their diorganotin(IV) counterparts. The complexes displayed sufficiently lower hemolytic effects in vitro as compared to triton X-100 and slightly higher than PBS. [ABSTRACT FROM AUTHOR]

In this article, we report the synthesis of two (A3 and A4) new ferrocene-based heterobimetallic compounds of Fe and Sn. Both compounds are structural isomers with formula (C5H5)Fe(C5H4C6H4COO)Sn(CH3)3 and have been characterized by elemental analysis, cyclic voltammetry, FTIR, UV–Vis and NMR spectroscopy. Additionally, the structure of A3 was confirmed by single-crystal XRD studies. XRD studies confirmed that in the solid phase A3 exists as a unidirectional polymeric material. DNA-binding potential of these compounds was evaluated by UV–Vis spectroscopy, cyclic voltammetry, and viscosity measurements. These interaction assays conclude that A3 (binding constant ~104 M−1) and A4 have good attraction toward DNA and bind with DNA in intercalative manner. [ABSTRACT FROM AUTHOR]

Two new heterobimetallic complexes of the composition [(VO2)2(μ3-slsch){Na2(μ-H2O)2(H2O)2}]n (1) and [(VO2)2(μ3-npsch){Na2(μ-H2O)2(H2O)2}(DMF)]n (2) were obtained by reaction of the ligand and vanadium pentoxide in a 1:1 molar ratio in methanol in the presence of Na2CO3 (2 equivalents). The complexes obtained were characterized using various spectroscopic studies. The structures of both the complexes were established by single crystal X-ray crystallographic study. We have also explored the catalytic behavior of the complexes in oxidative bromination of phenol red, which is the bio-inspired reaction catalyzed by an enzyme haloperoxidase. [ABSTRACT FROM AUTHOR]

The first examples of heterobimetallic Bi–Rh bonded complexes supported by heteroatom ligands have been synthesized and structurally characterized. BiRh(hp)4(1) and BiRh(chp)4(2) each adopt a [4,0]Opolar geometry with Bi–Rh bond distances of 2.5409(4) and 2.5848(1) Å, respectively (hp = 2-hydroxypyridine, chp = 6-chloro-2-hydroxypyridine). The relative oxophilicity of bismuth compared to rhodium clearly influences the selective formation of the [4,0]Oarrangement, even for the sterically crowded2. [ABSTRACT FROM AUTHOR]

Hydrogen has emerged as a leading alternative fuel; however, efficient chemical methods for generating hydrogen from water are lacking. Thus, chemists have turned to nature for inspiration. The [NiFe] hydrogenases possess rich structural, spectroscopic, and functional properties, motivating extensive synthetic efforts to model the complex active sites. In this comment, the geometric and electronic structures of the [NiFe] hydrogenases are compared to model compounds that most closely reproduce features of the native enzyme. The implications of this comparison and opportunities for advancing the catalytic activity of model compounds are discussed. [ABSTRACT FROM PUBLISHER]

[MnIIxFeII1−x(H2O)6][LiFeIII(ox)3] (with 0 ≤ x ≤ 1) crystallizes in the space groupP31cwitha = 9.341(3) Å,c = 10.226(3) Å,c/a = 1.0947, andV = 772.8(5) Å3forZ = 2. The compound has a layered structure with two enantiomeric layers per unit cell. The layers are built up by an iron and lithium oxalate framework with intercalated M(II)-water octahedra of the formula [MnIIxFeII1−x(H2O)6][MIMIII(ox)3]. The value ofxcannot be specified at present. The structure displays intermolecular hydrogen bonding between the layers. [ABSTRACT FROM AUTHOR]

Heterobimetallic complexes have been synthesized by stirring 2-mercapto-5-methylbenzimidazole with carbon disulfide in methanol at room temperature. In the second step, the product was treated with R2SnCl2/R3SnCl (R = Me,n-Bu, Ph) in 1 : 1 M ratio, then organotin(IV) complexes were treated with HgCl2in 2 : 1 M : L ratio to yield heterobimetallic complexes. The ligand and complexes have been characterized by elemental analysis, IR,1H- and13C NMR spectroscopy, mass spectrometry (EI-MS), and semiempirical study to assess the binding mode of the heterobimetallic complexes. IR data showed the bidentate nature of the dithiocarbamate moiety, which is also confirmed by semiempirical study. Mass spectra correspond to the expected for the complexes. NMR spectroscopy confirmed the four-coordinate geometry in solution. Computed molecular descriptors, thermodynamic parameters, and electrostatic surface potential map of4were calculated by using the PM6 method. Biological screening data indicated that complexes exhibit significant activity against various bacterial and fungal strains with few exceptions. Ligand and6are excellent for phagocyte reactive oxygen species inhibition. [ABSTRACT FROM PUBLISHER]

The present article describes the synthesis and reactivity of platinum-based trinuclear carbonyl clusters L2PtRu2(CO)8where L2 = 1,3-bis(diphenylphosphino)propane (dppp) and 1,2-bis(diphenylphosphino)ethane (dppe). Oxidative addition reactions of these bimetallic carbonyl clusters with methyl iodide yield products such as L2PtMeI and L2PtI2and Ru3(CO)12. On heating with diphenylacetylene, L2PtRu2(CO)8gives high yields of the corresponding products like L2PtRu2(CO)6(μ3-η2-PhC2Ph) (L = PPh3or L2 = dppe or dppp). Hydrogenation of (dppe)PtRu2(CO)6(μ3-η2-PhC2Ph) yields stilbene and a new carbonyl cluster, [(dppe)2Pt2Ru(CO)4] possessing two platinum centers of the type {Pt2Ru}. All the products were isolated and characterized by FT-IR, NMR, and mass spectral analysis. Reactivity of platinum-based trinuclear carbonyl clusters of the type L2PtRu2(CO)8, where L2 = 1,3-bis(diphenylphosphino)propane (dppp) and 1,2-bis(diphenylphosphino)ethane (dppe), is described. Oxidative addition reactions of these bimetallic carbonyl clusters with methyl iodide reveal the formation of products such as L2PtMeI and L2PtI2and Ru3(CO)12. On heating with diphenylacetylene, L2PtRu2(CO)8gave high yields of the corresponding products L2PtRu2(CO)6(μ3-η2-PhC2Ph) (L = PPh3or L2 = dppe or dppp). Hydrogenation of (dppe)PtRu2(CO)6(μ3-η2-PhC2Ph) yields stilbene and a new carbonyl cluster, [(dppe)2Pt2Ru(CO)4] possessing two platinum centers of the type {Pt2Ru}. All the products were isolated and characterized by FT-IR, NMR, and mass spectral analysis. [ABSTRACT FROM AUTHOR]

A palladium complex, [KLCSS]2Pd (1), has been prepared by stirring sarcosine (HLH), KOH and CS2in methanol and subsequently treating with palladium(II) chloride. Six heterobimetallic derivatives of the type [R2(Cl)SnLCS2]2Pd (R = Me:2; Bu:3; Ph:4)/[R3SnLCS2]2Pd (R = Me:5; Bu:6; Ph:7) were also synthesized by stirring sarcosine (HLH) with KOH and CS2in methanol followed by an addition of R2SnCl2/R3SnCl and then PdCl2. FT-IR data demonstrated bidentate binding of dithiocarbamate and carboxylate with four- and five-coordinate environments around Pd(II) and Sn(IV) centers, respectively, in the solid state. UV–visible studies verified the square planar arrangement around Pd(II) in solution. The magnitude of2J(119Sn-1H) demonstrates a distorted trigonal bipyramidal geometry around tin(IV) in solution. Elemental analysis (C, H, N, and S), mass spectroscopic (EI-MS and ESI), and thermogravimetric analyses verified the chemical composition of products. Complexes1–7exhibited interaction with salmon sperm DNA (SS-DNA). The palladium complex1had shown higher potential to bind with SS-DNA and to inhibit the alkaline phosphatase when compared to the heteronuclear products (2–7). However, the antifungal/antibacterial activities of the bimetallic complexes (2–7) were significantly higher than the palladated derivative1. Thein vitrohemolytic activity investigations on human red blood cells showed that bimetallic derivative2with chlorodimethyltin(IV) exhibited the lowest hemolytic effects (17.55%), while5having trimethyltin(IV) center exhibited the highest hemolytic activity (78.64%). A palladium complex and its heterobimetallic (Sn, Pd) derivatives were synthesized and characterized by spectroscopic and thermogravimetric analyses. The palladium complex showed higher potential to bind with SS-DNA and to inhibit the alkaline phosphatase (ALPs) relative to the heteronuclear products (2–7). However, the bimetallic derivatives displayed significantly higher antifungal/antibacterial activities than the palladium complex1. [ABSTRACT FROM PUBLISHER]

The heterobimetallic compound [Cu(amppz)(μ-NC)Fe(CN)4NO] (amppz = 1,4-bis(3-aminopropyl)piperazine) has been prepared by the reaction of [Cu(amppz)(ClO4)]ClO4and Na2[Fe(CN)5NO]⋅2H2O in aqueous solution and was characterized by IR spectroscopy, magnetic measurement, and X-ray single-crystal diffraction. The neutral complex has a cyanide-bridged binuclear structure in which the iron(II) is six-coordinate by five carbons from cyano groups (one of them forms a bridge) and one nitrogen from nitrosyl in an octahedral arrangement, whereas the copper(II) is five-coordinate by four amppz-nitrogens and one cyanide-nitrogen in a distorted square-pyramidal geometry. Magnetic investigation revealed a weak antiferromagnetic intermolecular interaction between the copper(II) ions withTN = 6 K. [ABSTRACT FROM PUBLISHER]

Three trinuclear sandwich-type cyanide-bridged MIII–NiIIcomplexes, {[Ni(cyclm)[Fe(bpb)(CN)2]2}·8H2O (1), {[Ni(cyclm)[Cr(bpb)(CN)2]2}·2H2O (2), and {[Ni(cyclm)[Co(bpb)(CN)2]2}·CH3OH·2H2O (3) (cyclm = 1,4,8,11-tetraazacyclotetradecane), have been synthesized using K[M(bpb)(CN)2] (M = Fe, Cr, Co; bpb = 1,2-bis(pyridine-2-carboxamido)benzenate) as building block and one Ni(II) compound containing a 14-membered macrocycle ring as assembling segment. All the complexes have been characterized by elemental analysis, IR spectroscopy, and X-ray structure determination. Single X-ray diffraction analysis shows similar sandwich-like structures, in which the two cyanide-containing building blocks are monodentate through one of their two cyanides, coordinated face to face to the central Ni(II). Investigation of the magnetic properties of1and2reveals ferromagnetic magnetic coupling between the neighboring Fe(III)/Cr(III) and Ni(II) through the bridging cyanide. A best-fit to the magnetic susceptibilities of1and2based on the trinuclear M2Ni model leads to magnetic coupling constantsJ = 5.47(1) cm−1for1andJ = 6.37(2) cm−1for2. [ABSTRACT FROM AUTHOR]

In the present study, a novel heterobimetallic [Mg(II)-Sn(IV)]-μ-oxoisopropoxide [MgO2Sn2(OPri)6] and its β-diketonates have been synthesized and characterized. The parent compound has been synthesized by the thermal condensation of magnesium acetate and tin(IV) isopropoxide. The isopropoxy substitution reactions of μ-oxoisopropoxide compound with β-diketones in different molar ratios (1:1–1:4) yielded the mono derivatives to tetra derivatives respectively of the parent compound. [{MgO2Sn2(OPri)6-nLn} (where n is 1–4 and L = acetylacetonate/benzoylacetonate anion)]. The μ-oxoisopropoxide compound has been characterized by liberated isopropanol, elemental, spectral (IR,1H,13C,119Sn NMR, and mass), thermal analysis, molecular weight data, and plausible structure is suggested. Some important reactions of [MgO2Sn2(OPri)6] with different β-diketones have revealed interesting facets in support of the suggested structure. The β-diketonates have been characterized by elemental, liberated isopropanol and spectral analysis (IR,1H,13C NMR). [ABSTRACT FROM PUBLISHER]

Heterobimetallic complexes [Cu x Zn1− x (dadb) · yH2O] n {where dadb = 2,5-diamino-3,6-dichloro-1,4-benzoquinone (1); x = 1 (2), 0.5 (4), 0.25 (5), 0.125 (6), 0.0625 (7), and 0 (3); y = 2; n = degree of polymerization} were synthesized and characterized. All metal complexes are stable at room temperature but weakly absorb moisture on exposure to air. Monometallic 2 exhibits subnormal magnetic moment whereas 3 exhibits diamagnetism. Heterobimetallic complexes exhibit normal magnetic moments. Heterobimetallic complexes are characterized from powder X-ray diffraction, thermal analysis, and electron spin resonance (ESR) spectral studies. Delocalization of unpaired electron from metal to ligand has been inferred from ESR and natural bond orbital (NBO) analysis. Greater delocalization of unpaired electron of Cu(II) on ligand of 4 as compared to that of 2 is reflected from NBO analysis. Heterobimetallic complexes show higher conductivity than monometallic complexes; all the complexes exhibit semiconductor behavior. [ABSTRACT FROM AUTHOR]

The coordination characteristic of diacetylmonoxime thiosemicarbazone {IUPAC name (E)-2-(E)-3-(hydroxyimino)butan-2- ylidene)-hydrazinecarbothioamide} (H2L) towards Ag(I), Fe(III), Co(II), Ni(II), and Cu(II) individually and in combination with Ag(1) has been studied. The prepared complexes are characterized by microanalysis, thermal, magnetic and spectral (IR, 1H NMR, ESR, and electronic) studies. Ag(1) plays an important role in the complex formation. The ligand chelates as: i) neutral in [Ag(H2L)(H2O)]·NO3·H2O, [Ag2(H2L)2]·2NO3·H2O and [Ag2(H2L)(OH)]·NO3; ii) monobasic in [Co(HL)2]·EtOH, [Fe(HL)2]·NO3, [FeAg2(HL)2(NO3)2]·NO3, and [Cu2(HL)2 (EtOH) (NO3)]·NO3·EtOH and iii) dibasic molecule in [Ni(L) (EtOH)], [NiAg2(L)2(EtOH)], [NiAg2(L)(H2O)2]·2NO3, [Cu2Ag2 (L)2(H2O)(NO3)]·NO3 and [Cu2Ag2(L)(H2O)3(OAc)2(NO3)]·NO3· H2O. The variation in coordination may be due to the presence of two different metal ions and the preparation conditions. The inside and outside nitrates are investigated by IR spectra; the ionic by a strong band at ≈ 1380 cm-1 and the coordinated by bands at ≈ 1434 and ≈ 1211 cm-1. The outer sphere solvents are detected by IR and thermal analysis. [ABSTRACT FROM AUTHOR]

The complex [MnIV(napbh)2] (napbhH2 = N-(2-hydroxynaphthalen-1-yl)methylenebenzoylhydrazide) reacts with activated ruthenium(III) chloride in methanol in 1 : 1.2 molar ratio under reflux, giving heterobimetallic complexes, [MnIV(napbh)2RuIIICl3(H2O)] · [RuIII(napbhH)Cl2(H2O)] reacts with Mn(OAc)2·4H2O in methanol in 1 : 1.2 molar ratio under reflux to give [RuIII(napbhH)Cl2(H2O)MnII(OAc)2]. Replacement of aquo in these heterobimetallic complexes has been observed when the reactions are carried out in the presence of pyridine (py), 3-picoline (3-pic), or 4-picoline (4-pic). The molar conductances for these complexes in DMF indicates 1 : 1 electrolytes. Magnetic moment values suggest that these heterobimetallic complexes contain MnIV and RuIII or RuIII and MnII in the same structural unit. Electronic spectral studies suggest six coordinate metal ions. IR spectra reveal that the napbhH2 ligand coordinates in its enol form to MnIV and bridges to RuIII and in the keto form to RuIII and bridging to MnII. [ABSTRACT FROM AUTHOR]

Polymeric heterobimetallic complexes of the type Ni[Ag(SCN)2]2.L (where L = acetophenone benzoylhydrazone (abh), acetophenone isonicotinoyl hydrazone (ainh), acetophenone salicyloyl hydrazone (ash), acetophenone anthraniloyl hydrazone (aah), p-hydroxy acetophenone benzoylhydrazone (phabh), p-hydroxy acetophenone isonicotinoyl hydrazone (phainh), p-hydroxy acetophenone salicyloyl hydrazone (phash) and p-hydroxy acetophenone anthraniloyl hydrazone (phaah) were synthesized and characterized with the help of elemental analyses, electrical conductance, magnetic moment, electronic and IR spectra, thermal and X-ray diffraction studies. Nickel(II) in the complexes has spin-free octahedral geometry. The hydrazone ligands are bi-coordinate bonding through > C═O and > C═N-groups. The complexes form a polymeric structure by bridging SCN groups between two metal centers. Thermal studies (TGA and DTA) on Ni[Ag(SCN)2]2.ash indicate multi-steps decomposition pattern which are both exothermic and endothermic. X-ray powder diffraction parameters for Ni[Ag(SCN)2]2.ash and Ni[Ag(SCN)2]2.phainh correspond to tetragonal and orthorhombic crystal lattices respectively. The ligands, as well as their complexes, show significant antifungal and antibacterial activity. The metal complexes are more active than the parent ligands. [ABSTRACT FROM AUTHOR]

Four new heterobimetallic complexes [CuL 1 ][MnCl 4 ] ( 1 ), [CuL 2 ][MnCl 4 ] ( 2 ), [NiL 1 ][MnCl 4 ] ( 3 ), [NiL 2 ][MnCl 4 ] ( 4 ) (L 1 = 4,6,6-trimethyl-1,9-diamino-3,7-di-aza-nona-3-ene; L 2 = 1,15-dihydroxy-7,9,9-trimethyl-3,6,10,13-tetra-aza-pentadeca-6-ene) have been prepared from elemental metals, ethylenediamine dihydrochloride or its N-(2-hydroxyethyl) derivative and acetone by the template condensation reaction. All complexes have been characterized by elemental analysis, IR and UV-Visible spectroscopy. The structures of 2 and 3 have been determined by X-ray crystallography ( 2 : Orthorhombic, Pna2 1, a = 20.136(4), b = 11.185(2), c = 10.251(2)Å, Z = 4; 3 : Orthorhombic, Pca2 1, a = 14.335(2), b = 11.405(2), c = 11.154(2)Å, Z = 4 ). Both crystals consist of alternating complex cations [ML] 2+ and anions [MnCl 4 ] 2- linked together by N-H···Cl-Mn and O-H···Cl-Mn hydrogen bonds forming 2D corrugated sheets in ( 2 ) and 1D helical chains in ( 3 ). Complex 2 represents the first single crystal structure elucidation of the complex containing L 2 . [ABSTRACT FROM AUTHOR]

Four heterobimetallic derivatives of the type, [R2(Cl)SnL]PdCl2(R = n-Bu:1)/[R3SnL]PdCl2(R = Me:2;n-Bu:3; Ph:4) where L = 4-(2-hydroxyethyl)piperazine-1-carbodithioic acid, have been synthesized by refluxing 4-(2-hydroxyethyl)piperazine-1-carbodithioic acid with R2SnCl2/R3SnCl in 1:1 M/L ratio and then stirring with PdCl2at room temperature. The complexes have been characterized by various spectroscopic (IR,1H and13C NMR, and EI-MS) techniques and thermogravimetric analysis. FTIR data demonstrated the bidentate binding of dithiocarbamate group. The NMR data demonstrated 4-coordinated geometry in solution. The complex4exhibits the interaction with salmon sperm DNA (SS-DNA) with significant hypochromic effect and suggests intercalating mode of binding. The complex2was found most active for inhibition of alkaline phosphates enzyme (ALPs). The complexes1–4showed significant antimicrobial activities as compared to the inactive free ligand precursor. Thein vitrohemolytic activity showed that average lysis of human red blood cells was significantly lower as compared to Triton-X 100 (positive control, 100% lysis). [ABSTRACT FROM AUTHOR]