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Dithiocarbamate Ligands (dithiocarbamate + ligand)
Selected AbstractsSynthesis, Solution-State and Solid-State Structural Characterization of Monocationic Nitrido Heterocomplexes [M(N)(DTC)(PNP)]+ (M = 99Tc, Re; DTC = Dithiocarbamate; PNP = Heterodiphosphane)EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 9 2004Cristina Bolzati Abstract Mono-cationic nitrido heterocomplexes of general formula [M(N)(DTC)(PNP)]+ (where M is 99Tc or Re, DTC is the mono-anionic form of a dithiocarbamate ligand, and PNP is a diphosphane ligand with a tertiary amine-containing five-membered spacer) were prepared by ligand-exchange reactions with the labile precursors [M(N)Cl2(PPh3)2] in dichloromethane/alcohol mixtures. The molecular structure of the representative rhenium complex [Re(N)(dedc)(pnp2)][PF6] (1) displays a distorted, square-pyramidal geometry with the dithiocarbamate sulfur and the diphosphane phosphorus atoms spanning the four coordination positions on the equatorial plane. If the additional interactions between the nitrido nitrogen and the weakly bonded transN -diphosphane heteroatom, the molecular geometry can be viewed as pseudo-octahedral. The structure in solution, as established by multinuclear NMR spectroscopy and ESI spectrometry, is monomeric, and identical to that shown in the solid state. Replacement of the phenyl groups on the phosphorous atoms in complexes 1, 2, 5, and 6 with alkyl groups modified neither the course of the reaction nor the composition of the resulting complexes. These results, together with the observation that no symmetrical complexes containing two identical bidentate ligands were produced in these reactions, strongly supports the conclusion that a mixed coordination sphere, composed by a combination of ,-donor and ,-acceptor atoms around the [M,N]2+ group, constitutes a highly stable system. Compounds containing dangling alkyl-substituted groups in the outer sphere (3, 4, 7, and 8) were fully characterized by multinuclear NMR spectroscopy and ESI mass spectrometry. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source] Synthesis and biological evaluation of a novel asymmetrical 99mTc-nitrido complex of metronidazole derivativeJOURNAL OF LABELLED COMPOUNDS AND RADIOPHARMACEUTICALS, Issue 13 2007Dejing Kong Abstract The novel dithiocarbamate derivative of metronidazole, potassium 2-(2-methyl-5-nitro-1H -imidazolyl)-ethyl-dithiocarbamate (MNIE-DTC), was synthesized as the pharmacophore-containing bifunctional ligand. The corresponding asymmetrical 99mTc-nitrido complex, expected as a tumor hypoxia marker, had been successfully obtained by the addition of the biphosphine ligand PNP5 (PNP5 = N -ethoxethyl- N,N -bis[2-(bis(3-methoxypropyl)phosphino)ethyl]-amine) and the dithiocarbamate ligand (MNIE-DTC) to the 99mTc-nitrido precursor solution at 100°C for 15 min. The radiochemical purity of the product was above 95% as measured by thin-layer chromatography and high-performance liquid chromatography. In vitro studies showed that the complex possessed good stability under physiological conditions. Its partition coefficient studies indicated that it was a lipophilic complex. The electrophoresis results showed that the complex was cationic. Biological evaluation of the complex [99mTcN(PNP5)(MNIE-DTC)]+ performed in Kunming mice bearing H22 tumor showed that the complex had a moderate tumor uptake (0.57±0.06%ID/g at 1h), and the ratios of tumor/blood and tumor/muscle were 2.46 and 1.31 at 1h p.i., and reached 4.52 and 2.86 at 4h p.i., respectively. Copyright © 2007 John Wiley & Sons, Ltd. [source] Synthesis, structure characterization and insecticidal activity of some triorganotin dithiocarbamatesAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 4 2003George Eng Abstract A series of triorganotin dithiocarbamates has been synthesized using a low-temperature method. Their structures have been characterized by IR, Mössbauer and NMR spectroscopies. In the solid state, an unsymmetrical chelation of the dithiocarbamate ligand was found in all the compounds synthesized. The observation of two SnS distances in the compounds was confirmed in the crystal structure of tricyclohexyltin N - n -butyldithiocarbamate. In solution, the compounds were found to exhibit distorted tetrahedral structures. The insecticidal activities of the title compounds were screened against the second larval instar of the Anopheles stephensi Liston and Aedes aegypti (L.) mosquitoes. Results from the screening studies indicated that the triorganotin dithiocarbamates were effective larvicides against both species of larvae. However, there were no significant activity differences between the triphenyltin and tricyclohexyltin derivatives. A quantitative structure,activity relationship was also developed for the An. stephensi. Copyright © 2003 John Wiley & Sons, Ltd. [source] Synthesis and spectral studies of diorganotin heterocyclic dithiocarbamate complexes and crystal structures of (2- F -Bz)2Sn(Cl) S2CN(CH2CH2)2NEt and (3- Cl -Bz)2Sn [S2CN(CH2CH2)2NEt]2 , 0.5HN(CH2CH2)2NHHETEROATOM CHEMISTRY, Issue 4 2005Shengcai Xue Some new diorganotin(IV) complexes of heterocyclic dithiocarbamate having general formula R2Sn(Cl)S2CNR'2 and R2Sn(S2CNR'2)2 [R = 2-F-Bz, 3-Cl-Bz; NR'2 = N(CH2CH2)2NMe, N(CH2CH2)2NEt, and N(CH2CH2)2NBz] have been prepared, respectively. Elemental analyses, IR, and NMR spectral data characterized all compounds. The crystal structures of (2-F-Bz)2Sn(Cl)S2CN(CH2CH2)2NEt 2 and (3-Cl-Bz)2Sn[S2CN(CH2CH2)2NEt]2 , 0.5 HN(CH2CH2)2NH 5 were determined by single crystal X-ray diffractometer. In the crystal of complex 2, the tin atom is rendered five-coordination in a trigonal bipyramidal configuration by coordinating with S atoms of dithiocarbamate groups. For complex 5, the central Sn atom exists in a skew-trapezoidal planar geometry defined by two asymmetrically coordinated dithiocarbamate ligands and two 3-chlorobenzyl groups. © 2005 Wiley Periodicals, Inc. 16:271,277, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20096 [source] Characterisation via electrospray ionisation multistage mass spectrometry of three related series of nitrido technetium complexes containing phosphinothiolate and dithiocarbamate ligandsRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 13 2005Michela Tubaro Nine nitrido technetium compounds comprising bis-substituted Tc(N)(PS)2 (1,4) (PS,=,bidentate phosphinothiolate ligands) and Tc(N)(dtc)2 (5, 6) derivatives (dtc,=,bidentate dithiocarbamate), and mixed-ligand Tc(N)(PS)(dtc) (7,9) species, were subjected to electrospray ionisation mass spectrometry and MSn experiments. Bis-substituted phosphinothiolato complexes 1,4 lead to the straightforward formation of dinuclear species reasonably originating from proton bound dimers. These dinuclear species do not show, under collisionally induced fragmentation processes, the formation of monomeric units but cleavages related to the ligand framework, thereby proving the high stability of the [TcH+Tc] bond. Bis-dithiocarbamate compounds 5 and 6 show, instead, abundant [M+H]+, [M+Na]+ and [2M+Na]+ ions, and their collisionally induced fragmentations are highly favoured with cleavages related to the CN and CS bonds. During these processes, the coordination of a water molecule to [MH,L]+ product ions is observed, as proved by the collisionally induced H2O loss detected for this species. Mixed-ligand compounds 7 and 8 show the protonated molecules and Na+ -cationised ions with fragmentation processes related to the dithiocarbamate moiety. This behaviour indicates that coordination of ether- and ester-substituted dithiocarbamates to the [Tc,,N] group is weaker than that of phosphinothiolates. Conversely, diethyldithiocarbamate inserted in mixed complex 9 enhances both CN and TcS bonds, and fragmentation processes suggest that metal-phosphinothiolate and metal-dithiocarbamate show comparable strength. Copyright © 2005 John Wiley & Sons, Ltd. [source] Crystallographic report: Bis(N,N -dibenzyldithiocarbamato)zinc(II)APPLIED ORGANOMETALLIC CHEMISTRY, Issue 2 2004Andreas Decken Abstract The structure of Zn[S2CN(CH2Ph)2]2 features, in contrast to many related analogues, a mononuclear species with two chelating dithiocarbamate ligands that form a distorted tetrahedral array around the zinc centre; the molecule has two-fold symmetry. Copyright © 2004 John Wiley & Sons, Ltd. [source] Crystallographic report: Tris(N,N -dimethyldithiocarbamato)arsenic(III) dichloromethane solvateAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 10 2003Danlin Chen Abstract The structure of As(S2CNMe2)3 has approximate threefold symmetry and features essentially monodentate dithiocarbamate ligands, so that the geometry is trigonal pyramidal. Copyright © 2003 John Wiley & Sons, Ltd. [source] Crystallographic report: (2,9-Dimethyl-1,10-phenanthroline)bis-(N,N -pyrrolidinedithiocarbamato)zinc(II) chloroform hemihydrateAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 4 2003Chian Sing Lai Abstract The mononuclear structure of Zn(S2C(N(CH2)2)4)2(2,9-Me2 -1,10-phen) shows monodentate coordination by the dithiocarbamate ligands and a distorted tetrahedral geometry for zinc, defined by an N2S2 donor set, results. Copyright © 2003 John Wiley & Sons, Ltd. [source] | ||||||||||