Organometallic complexes with biological molecules

Novel triorganotin(IV) complexes of two beta-lactamic antibiotics, 6-[D-(-)-beta-amino-p-hydroxyphenyl-acetamido]penicillin (=amoxicillin) and 6-[D-(-)-alpha-aminobenzyl]penicillin (=ampicillin), have been synthesized and investigated both in solid and solution states. The complexes corresponded to the general formula R(3)Sn(IV)antib*H(2)O (R=Me, n-Bu, Ph; antib=amox=amoxicillinate or amp=ampicillinate). Structural investigations about configuration in the solid state have been carried out by interpreting experimental IR and 119Sn Mossbauer data. In particular, IR results suggested polymeric structures both for R(3)Sn(IV)amox.H(2)O and R(3)Sn(IV)amp*H(2)O. Moreover, both antibiotics appear …

Spectroscopic characterization and biological activity ofL-methionyl-L histidinato complexes of R2Sn(IV) ions (R?=?Me, nBu, Ph) and X-ray structure of Me2SnMetHis ? 0.5MeOH

Complexes of L-methionyl-L-histidine (H2MetHis) with R2Sn(IV) ions (R = Me, nBu, Ph) have been synthesized. The crystal and molecular structures of Me2SnMetHis·0.5MeOH have been determined by X-ray diffraction. The title compound contains two crystallographically independent molecular units possessing the same trigonal-bipyramidal geometry at tin, each dimethyltin(IV) moiety being coordinated by the terminal amino nitrogen, deprotonated peptide nitrogen and terminal carboxylate group, neither the imidazole nor thioether groups being involved in bonding. IR spectroscopy was used to probe the structure of the complexes in the solid state, and the structure in solution (CD3OD) was assessed by …

Anti-tumor activity of two binuclear gold(I) complexes with bridging dithiolate ligands

Abstract Two new binuclear complexes of gold with bridging dithiolate ligands were synthesized and characterized: (o3PAu)2(μ-DTE) and (Et3PAu)2(μ-DMTA); H2DTE=dithioerylthritol and H2DMTA=2,5-dimer- capto-1-thia-3,4-diazole. These compounds and three gold compounds with antiarthritic activity (gold sodium thiomalate, gold thioglucose and Et3PAuCl) were tested for antitumor activity using the Ehrlich- Ascites tumor cell in mice. Only (o3PAu)e(μ-DTE) showed significant activity.

Complexes of Tin(IV) with Tridentate Ligands M�SSBAUER, Infrared, and Solution Phase Studies

The configuration in the solid state and in solution phase of complexes of SuIV wit,li tridentate “planar” ligands, Sn(trid)2 and HNEt3Cl3 Sntrid, have been investigated by infrared and MOSSBAUER spectroscopy, as well as by osmometry, conductivity, and electronic and PMR spectroscopy. The presence of monomeric Sn(trid)2 and ionic [HNEt] [Cl3Sn trid−] species has been inferred. Octahedral type configurations are advanced for both classes of compounds. Komplexe des Zinn (IV) mit dreizahigen Liganden. Mossbauer- und IR-Spektren sowie Untersuchungen von Losungen Die Struktur von SnIV-Komplexen mit dreizahnigen “planaren” Liganden, Sn(trid)2 und HNEt3Cl2Sntrid, wurde in fester Phase und in Losun…

Infrared and M�SSBAUER spectroscopic studies on complexes of Hal2SnIV moieties with tridentate ligands

Novel complexes hal2Sntrid, where hal Cl, Br, and trid2− are dianions of „planar” tridentate ligands with ONO and SNO donor basic atoms, were synthesized and structurally investigated in the solid state mainly by far infrared and MOSSBAUER spectroscopy. Possible configurations were advanced and discussed, and it was concluded that the most probable is a monomeric trigonal bipyramidal structure for all compounds, although polymers, or dimers with O or Cl bridges, were not a priori excluded, in a special way for Br2Sntrid. Infrarot- und MOSSBAUER-spektroskopische Untersuchungen an Komplexen von Hal2SnIV mit dreizahnigen Liganden Neue Komplexverbindungen von Typ hal2Sntrid werden dargestellt (…

ChemInform Abstract: Organoelement Derivatives of Steroids: Synthesis and Structural Characterization of Diorganotin Chloride Adducts of Hormones.

Abstract Ten new diorganotin dichloride adducts of hormones of the type R 2 SnCl 2 ·2L [where R = Me, Et, n-Bu, Oct and Ph; L = 4-androsten-17s-ol-3-one ( A ); 5-androsten-3s-ol-17-one ( B ); 4-androsten-17α- methyl-17s-ol-3-one ( C ) and 3,17-dihydroxy-5- pregnene-20-one ( D )] have been prepared and characterized at 297 K and 223 K. Spectroscopic measurements (IR; Raman; 1 H, 13 C, 119 Sn NMR) suggest the dissociation or fast ligand exchange in solution at 297 K. Hexa-coordinated adducts with bonding through carbonyl oxygen and trans -R groups in octahedral geometry are formulated at 223 K.

119Sn mössbauer, IR, 1H NMR spectroscopic and thermal decomposition studies on organotin(IV) adducts with glycylglycine

Abstract The complexes R2SnCl2·(H2glygly), (H2glygly = glycylglycine) (R = Me, Bun, Octn, Ph) and RSnCl3·(H2glygly)

Diorganotin(IV) dipeptide complexes with potential antitumour activity

A series of complexes of the dimethylltin(IV) moiety with dipeptides has been synthesized. The dipeptides are L-alanyl-L-histidine (H2AlaHis), L-methionyl-L-methionine (H2MetMet), L-glycyl-L-histidine (H2GlyHis) and L-histidyl-L-glycine (H2HisGly). The complexes have been characterized by IR and 119Sn Mossbauer spectroscopy in the solid state and by 1H NMR in CD3OD and D2O solutions. They consist of monomeric entities, with the tin atom arranged in a pentacoordinated trigonal bipyramidal structure. The dipeptides are coordinated via the amino group, deprotonated peptide nitrogen and carboxylate group. Neither imidazole in histidine-containing dipetides, nor the thioether group in MetMet, is…

Synthesis, characterization, and cytotoxic activity of copper(II) and platinum(II) complexes of 2-benzoylpyrrole and X-ray structure of bis[2-benzoylpyrrolato(N,O)]copper(II).

Copper(II) and platinum(II) complexes of 2-benzoylpyrrole (2-BZPH) were synthesized and characterized with IR, 1 H and 1 3 C NMR spectroscopies and coordination geometry with ligands arranged in transoid fashion. The crystal structure of [Cu I I (2-BZP) 2 ] was determined by X-ray diffraction. Death of complex treated Jurkat cells was measured by flow cytometry. The bis-chelate complexes [Cu I I (2-BZP) 2 ] and [Pt I I (2-BZP) 2 ] adopt square-planar coordination geometry with ligands, arranged in transoid fashion. Concentrations of 1-10 μM Platinum(II) complexes reduced cell survival from 100% to 20%, in contrast to the copper(II) complex which caused no cell death at a concentration of 10…

Mössbauer studies on tin(IV) and organotin(IV) diacetylbis(benzoylhydrazone) complexes

Abstract The Mossbauer parameters of Ph 2 SnDB, PhClSnDB and Sn(DB) 2 were determined, where DB 2− is the dianion of the multidentate ligand diacetylbis(benzoylhydrazone). According also to data treatment with the point charge model formalism, the configurations of Ph 2 Sn IV and PhSn IV derivatives appear to be essentially octahedral, with linear CSnC and CSnCl skeletons. As to Sn(DB) 2 , it appears that the electrical charge density at the Sn IV nucleus has a cubic symmetry, which is consistent with both tetrahedral and octahedral configurations around Sn IV .

Infrared and Mössbauer studies on adducts R3SnOH · R3MX (M = Sn, Pb; X = Pseudohalide)

Abstract The synthesis of the solid adducts Me3SnOH · Me3 SnNCO, Me3SnOH · Me3SnNCS, Me3SnOH · Me3PbN3, Ph3SnOH · Ph3SnN3 is reported. The compounds have been investigated by infrared and Mossbauer spectroscopy. Their structure probably consists of polymeric OH-R3Sn-X-R3Sn(Pb) chains in which hydroxyl and pseudohalide (X) groups are bridging pentacoordinate tin atoms. In contrast to the triphenyl compound, the trimethyl derivatives show evidence of hydrogen bonding between adjacent chains.

Complexes of organometallic compounds

Abstract Tetraphenylarsonium and tetramethylammonium salts of the complex anions Ph 3 Pb(N 3 ) − 2 , Ph 3 Pb(N 3 )(NCS) − , Ph 2 Pb(N 3 ( 2 − 4 )) and Ph 2 Pb(N 3 )(NCS) − 2 have been prepared and characterized. Infrared spectra and solution conductance data are reported. Possible configurations of the complex anions are discussed.

Organomercury(II) derivatives of 2-thiouracil. An infrared and proton magnetic resonance study of structures

Abstract The novel complexes RHg(s2UraH−1) (R = Me, Ph) where s2UraH−1 is the monoanion of 2-thiouracil, have been synthesized. Comparison of the infrared spectra of the solid complexes and of 1H nuclear magnetic resonance spectra of the complexes in dimethyl-d6 sulfoxide with spectra of s2 Ura and Na[s2UraH−1] allows the recognition of the existence of isomers in the solid, with bonding to exocyclic sulfur and to pyrimidine nitrogens. In solution, a simpler pattern is observed, with 2J(1H199Hg) indicating bonding to sulfur only.

Complexes of Organometallic Compounds. XXVII. Studies on Diorganolead (IV) Moieties Six-coordinated by ONNO Tetradentate Ligands

New complexes R2PbL, where L2− are the dianions in the “planar” SCHIFF base form, of the tetradentate ONNO ligands α, α′ (ethylenedinitrilo)dicresol and 2,2′ bis-benzoxazoline, were synthesized. Their configuration was investigated at the solid state by infrared spectroscopy, and in solution phase mainly by electronic and PMR spectroscopy. An octahedral type structure with linear CPbC moieties, and the ONNO ligand atoms chelating PbIV in a square plane, was advanced. Darstellung neuer Komplexverbindungen: R2PbL (R = CH3, C2H5, C6H5; L−2 sind zweiwertige Anionen, in der „planaren” SCHIFFSCHEN Basen-Konfiguration, der vierzahnigen ONNO-Liganden Disalicylal-athylendiamin und Glyoxal-bis-[2-hyd…

Synthesis, structural characterisation and biological studies of new mononuclear platinum(II) complexes with sterically hindered heterocyclic ligands

Abstract Three novel cisplatin analogues were synthesized, designed according to an approach which violates the “classical” structure–activity relationship, by replacing the diamine ligands with a planar N donor heterocycle giving a sterically hindered complex. Moreover, the sterical hindrance of antitumor drug candidates potentially makes them less susceptible to deactivation by sulphur-containing proteins and helping to overcome resistance mechanisms. The resulting mononuclear complexes of sterically hindered polidentate heterocyclic N ligands [PtCl(bbp)]Cl ( 1 ) [bbp = 2,6-bis(2-benzimidazolyl)pyridine], [PtCl 2 (dptdn)](H 2 O) ( 2 ) [dptdn = sodium 5,6-diphenyl-3-(2′-pyridyl)-1,2,4-tria…

Organometallic Complexes with Biological Molecules: VII. Dialkyl- and Trialkyl-tin (IV)[meso-tetra(4-carboxyphenyl)porphinate] Derivatives: Solid-state, Solution-phase Structural Aspects andIn Vivo Effects

The synthesis, the structural features and the in vivo biological activity of diorganotin(IV) and triorganotin(IV) derivatives of [meso-tetra(4-carboxyphenyl)porphine] (H 4 TPPC) are reported. Derivatives with general formula (R 2 Sn) 2 TPPC and (R 3 Sn) 4 TPPC (R=Me, Bu, and Ph) were obtained, and the main information extracted from the infrared and Mossbauer spectral data, in the solid state, was in favor of the occurrence of five-coordinated tin(IV) atoms, in a polymeric trigonal-bipyramidal configuration, attained through two differently coordinated, estertype and chelating respectively, carboxylate anions in [R 2 Sn] 2 TPPC, while in [Alk 3 Sn] 4 TPPC five-coordination of the tin(IV) a…

Organomercury(II) and organothallium(III) complexes with Cis-1,2-dicyanoethylenedithiolate ion

Organotin(IV) derivatives of the ambidentate ligand 2-thiouracil. Infrared, Mössbauer, 1H and 13C NMR studies

Abstract Complexes Bu 2 n Sn(s 2 UraH −2 and [Me 2 SnOH] 2 (s 2 UraH −2 have been synthesized. Comparison of infrared spectra of the solid complexes with spectra of s 2 Ura and (PhHg) 2 (s 2 UraH −2 complex and point charge calculations (Mossbauer spectra) allow assignment of structures for the complexes of this ambivalent ligand. Polymeric structures are proposed for the complexes in the solid state, where the organometallic moieties are bonded to exocyclic S and N(3) atoms of the dianionic base, with formation of a four-membered chelate ring for Bu 2 n Sn(s 2 UraH −2 ). For [Me 2 SnOH] 2 (s 2 UraH −2 , 1 H and 13 C NMR data suggest retention of penta-coordination in trifluoacetic acid sol…

Complexes of organothallium(III) with Cis-1,2-dicyanoethylenedithiolate ion and a ‘tripod’ ligand. Synthesis, infrared and proton magnetic resonance spectra and reactivity

Abstract The reaction of cis-1,2-dicyanoethylenedithiolate ion (mnt2− with organothallium(III) derivatives has been examined. The complexes [(CH3)2Tl]2mnt and [(C4H9)4N] [(C6H5)2Tl mnt] have been synthesized. The results seem to indicate a trend in reactivity similar to that of arylmercury(II) derivatives towards chelating agents with nucleophilic character. In addition, the complex [(CH3)2Tl(tren)] [BPh4] has been obtained as a test of the complexing ability of 2,2′, 2″-triaminotriethylamine(tren) towards organometallic moieties. I.r. and 1H n.m.r. are presented and discussed.

Complexes of tryptophan dipeptides with the R2Sn(IV)2+ ion (R=Me, Ph): Spectroscopic studies, solution properties and structural implications

Tryptophan dipeptides such as L-tryptophyl-L-alanine (H 2 TrpAla), L-tryptophyl-L-tyrosine (H 2 TrpTyr), L-tryptophyl-L-tryptophan (H 2 TrpTrp), along with L-histidyl-L-tyrosine (H 2 HisTyr), were reacted with R 2 SnO (R=Me, Ph) yielding the corresponding complexes. The complexes have been characterized by IR and 119 Sn Mossbauer spectroscopy in the solid state and by 1 H and 13 C NMR in CD 3 OD solutions. Monomeric species were detected, with the tin atom arranged in a pentacoordinated trigonal-bipyramidal structure. The dipeptides are coordinated via the terminal amino group, deprotonated peptide nitrogen and terminal carboxylate group. No side-chain appears to be involved in bonding. Det…

Organometallic complexes with biological molecules: XIII. Organotin(IV)[meso-tetra (4-carboxyphenyl)porphinate]s and the cell cycle: a flow-cytometric approach

The cytotoxic derivatives diorganotin(IV) and triorganotin(IV) [meso-tetra(4-carboxyphenyl)porphinates, with stoichiometries [R2Sn]2TPPC and [R3Sn]4TPPC [R = Me, Bu, Ph; TPPC4−­= meso-tetra(4-carboxyphenyl)porphinate4−], namely bis[dimethyltin(IV)], bis[dibutyltin(IV)], bis[diphenyltin(IV)], tetra[trimethyltin(IV)], tetra[tributyltin(IV)] and tetra[triphenyltin(IV)] [meso-tetra(4-carboxyphenyl)porphinate]s, have been used to investigate their effects on the cultured human kidney cell cycle in order to understand further the origin of cell-growth inhibition induced by the above-mentioned chemicals. The cell-cycle-dependent DNA content distribution of cultured cells exposed to these compounds…

Mono- and polynuclear complexes of Pt(II) with polypyridyl ligands. Synthesis, spectroscopic and structural characterization and cytotoxic activity.

Abstract An array of poly- and mononuclear complexes of Pt(II) with polypyridyl ligands is reported. The framework complexes [(PtCl 2 ) 2 (bpp) 2 (μ-PtCl 2 )](H 2 O) 2 [bpp = 2,3-bis(2-pyridyl)pyrazine], [PtCl 2 (μ-tptz)PtClNCPh]Cl [tptz = 2,4,6-tris(2-pyridyl)-1,3,5-triazine], and mononuclear PtCl 2 (NH 2 dpt) [NH 2 dpt = 4-amino-3,5-bis(2-pyridyl)-1,2,4-triazole] have been prepared and structurally characterized. Both neutral and ionic complexes are present, with bifunctional and monofunctional Pt(II) moieties, whose size and shape enable them to behave as novel scaffolds for DNA binding. Pt(II) complexes were tested for their biological activity. Cell viability assay and flow cytometric …

Synthetic, structural and biochemical studies of polynuclear platinum(II) complexes with heterocyclic ligands.

"Non-classical" di- and trinuclear Pt(II) complexes with polydentate nitrogen ligands; ionic [(PtCl(2))(2)(tptz)(2)(mu-PtClNCPh)]Cl (1) [tptz =2,4,6-tris(2-pyridyl)-1,3,5-triazine], [(PtCl(2))(2)(bptz)(2)(mu-Pt)]Cl(2) (2) [bptz = 3,6-bis(2-pyridyl)-1,2,4,5-tetrazine] and neutral [(PtCl(2))(2)(tptz)(2)(mu-PtCl(2))](H(2)O)(4) (3), [(PtCl(2))(2)(mu-tppz)](CHCl(3)) (4) [tppz = 2,3,5,6-tetra(2-pyridyl)pyrazine] complexes, have been prepared and structurally characterized. The neutral tptz and tppz complexes present three and two separate PtCl(2) moieties, respectively, in a cis position, presumably acting in a bifunctional mode towards DNA; the cationic tptz and bptz complexes contain monofuncti…

Mössbauer spectroscopy of mono-organotin(IV) derivatives

Abstract The Mossbauer parameters isomer shift, δ, and quadrupole splitting, ΔE, of mono-organotin compounds insofar investigated have been collected and tabulated. It is demonstrated that isomer shifts consistently depend on ligand electronegativities and coordination numbers, from which it is deduced that RSn IV behave much more as Sn IV rather than R 2 Sn IV and R 3 Sn IV derivatives. The changes of δ for RSn IV are then interpreted by hypotheses analogous to those advanced for Sn IV and its adducts and complexes. It is also inferred that in RSn IV compounds there is a consistent s-character in all tin-ligand atom bonds.

SYNTHESIS, LASER-RAMAN, INFRARED AND PROTON MAGNETIC RESONANCE SPECTRA OF (CH3)3PtX2- 3 IONS (X = Cl−, Br−) AND (CH3)3Ptiv ISOCYANIDE COMPLEXES

Abstract The novel ionic complexes [(C6H5)4As]2 [(CH3)3PtX3](X = Cl− and Br−) and [(CH3)3Pt(bipy)L]+[B(C6H5)4]− (bipy = 2,2′-bipyridine, L = aliphatic and aromatic isocyanide) have been prepared. The structure of the complex ions has been inferred from Laser-Raman and infrared spectra in the solid state and 1H NMR in solution. These data are consistent with a facial configuration of the organometallic moiety. Trends in vibrational frequencies ν(Pt-C) and ν(Pt-X) indicate a “trans” influence sequence for the ligands, which in the case of (CH3)3PtX2- 3 is related with that found for (CH3)2AuX− 2 ions.

An infrared study of organothallium thiocyanates

Abstract Some structural aspects of the organothallium(III) thiocyanates R 2 TlCNS (R = Me, Ph).[Ph 4 As][Me 2 Tl(CNS) 2 ] and Phtl(CNS) 2 have been studied by IR spectroscopy. From the frequencies of the NCS group vibrations in the solids, and the integrated intensity of the C≡N stretching absorption in solution, it was ascertained that the diorganothallium derivatives are isothiocyanates with a certain amount of ionic character in the TlNCS bonds, whereas PhTl(CNS), is essentially a TlSCN bonded compound. Apparently both solid Me 2 TlCNS and [Ph 4 As][Me 2 Tl(CNS) 2 ] do not show IR active ν s (TlC 2 )bands. The compound Me 2 TlCNS displays a double ν as (TlC 2 band, from which the pres…

Organoelement derivatives of steroids: synthesis and structural characterization of diorganotin chloride adducts of hormones

Abstract Ten new diorganotin dichloride adducts of hormones of the type R 2 SnCl 2 ·2L [where R = Me, Et, n-Bu, Oct and Ph; L = 4-androsten-17s-ol-3-one ( A ); 5-androsten-3s-ol-17-one ( B ); 4-androsten-17α- methyl-17s-ol-3-one ( C ) and 3,17-dihydroxy-5- pregnene-20-one ( D )] have been prepared and characterized at 297 K and 223 K. Spectroscopic measurements (IR; Raman; 1 H, 13 C, 119 Sn NMR) suggest the dissociation or fast ligand exchange in solution at 297 K. Hexa-coordinated adducts with bonding through carbonyl oxygen and trans -R groups in octahedral geometry are formulated at 223 K.

Corrigendum: Organometallic complexes with biological molecules: VII. Diorgano- and triorgano-tin(IV)[meso-tetra(4-carboxyphenyl)porphinate] derivatives: solid-state, solution-phase structural aspects andin vivo effects

Organometallic complexes with biological molecules, IV. Di- and tri-organotin(IV) amoxicillin derivatives: Solid-state and solution-phase spectroscopic investigations

Novel di- and tri-organotin(IV) derivatives of amoxicillin (amoxicillin - =Amox - =6-[D(-)-β-amino-p-hydroxyphenylacetamido] penicillinate) have been prepared. The isolated compounds showed stoichiometries of the type R 2 SnClAmox.2H 2 O, R 3 SnClAmoxNa.2H 2 O and R 2 SnAmox 2 .2H 2 O (R=Me, Bu, Ph). The infrared spectra suggest that Amox − , in both R 2 SnClAmox.2H 2 O and R 2 SnAmox 2 .2H 2 O, behaves as a monoanionic bidentate ligand, coordinating the tin(IV) atom through the ester-type carboxylate, as well as through the lactamic carbonyl. In R 3 SnClAmoxNa.2H 2 O, Amox - coordinates the organotin(IV) moieties through the lactamic carbonyl. In all of the compounds, water molecules are n…

Complexes of (CH3)2AuIII: synthesis, PMR and IR spectra

Abstract The syntheses and reactivity of dimethylgold(III) complexes with multidentate ligands as TRIPHOS (i.e., 1,1,1-tris(diphenylphosphinomethyl)ethane) and TREN (i.e. 2,2′,2″-triaminotriethylamine) have been examined. I.r. spectra for the compounds in the solid state, conductivity and PMR data for solutions, lead to the assignment of an ionic formula [CH 3 ) 2 Au TRIPHOS] + [(CH 3 ) 2 AuCl 2 ] − where the gold(III) atoms are presumably four-coordinate. The complex (CH 3 ) 2 AuCl TREN in DMSO solution undergoes a reductive elimination reaction, as found for analogous dimethylgold(III) derivatives.