Estudi de complexos formats pels lligands 3-amino-1- prorantiol i 3-(dimetilamino)-1-propantiol amb metalls de transició i amb metalls del grup iib

Consultable des del TDXTítol obtingut de la portada digitalitzad

Un nou mètode per sintetitzar compostos de tecneci i fabricar radiofàrmacs

La ràpida semidesintegració de l'isòtop de tecneci emprat per elaborar radiofàrmarcs ha portat al grup Síntesi i aplicacions bioorgàniques i bioinorgàniques de la UAB a dissenyar un nou mètode de preparació de compostos de tecneci radioactius mitjançant el bescanvi amb un element no radioactiu (zinc). La nova molècula resultant marca els liposomes, estructures que permeten l'encapsulament de fàrmacs i que poden ser de gran utilitat en la diagnosi i teràpia de malalties.La rápida semidesintegración del isótopo de tecnecio empleado para elaborar radiofármarcos ha llevado al grupo Síntesis y aplicaciones bioorgánicas y bioinorgánicas de la UAB a diseñar un nuevo método de preparación de compuestos de tecnecio radiactivos mediante el intercambio con un elemento no radiactivo (zinc). La nueva molécula resultante marca los liposomas, estructuras que permiten la encapsulación de fármacos y que pueden ser de gran utilidad en el diagnóstico y terapia de enfermedades

Formation of vesicles with an organometallic amphiphilic bilayer by supramolecular arrangement of metal carbonyl metallosurfactants

Metallo-vesicles are formed in water medium as a result of the supramolecular arrangement of molybdenum carbonyl metallosurfactants. These new kind of surfactants contain a hydrophobic metal carbonyl fragment and are easily prepared from surfactant phosphine ligand

New rhenium complexes with ciprofloxacin as useful models for understanding the properties of [99mTc]-ciprofloxacin radiopharmaceutical

Rhenium complexes with the antibiotic ciprofloxacin have been prepared to be studied as models of technetium radiopharmaceuticals. With this aim, the new rhenium complexes 1 {[ReO(Cpf)2]Cl}, 2 {[ReO(CpfH)2]Cl3} and 3 {fac-[Re(CO)3(H2O)(Cpf)]} with ciprofloxacin (CpfH=ciprofloxacin; Cpf=conjugated base of ciprofloxacin) have been synthesised and characterised by elemental analyses, IR, NMR ((1)H, (19)F and (13)C CP-MAS) spectroscopy, as well as MS measurements. All spectroscopic data are consistent with the coordination of ciprofloxacin in all these complexes through the carbonyl and the carboxylate oxygen atoms with the formation of a six member chelate ring. The study of a Tc-ciprofloxacin solution by ESI-MS reveals the presence of [TcO(Cpf)2](+) cations, which agrees with the hypothesis that complexes 1 and 2 can be seen as model rhenium complexes of this radiopharmaceutical. Antimicrobial and DNA gyrase inhibition studies performed with complexes 2 and 3 have shown a very similar behaviour between complex 2 and the free antibiotic, whereas complex 3 exhibit a lower antimicrobial activity. Based on a joint analysis of the data reported in the literature and the chemical and biological results obtained in this study, a tentative proposal to explain some aspects of the behaviour of Tc-ciprofloxacin radiopharmaceutical has been made

Bioconjugated technetium carbonyls by transmetalation reaction with zinc derivatives

Altres ajuts: Acord transformatiu CRUE-CSICThe transmetalation reaction between zinc dithiocarbamates functionalized with organic groups and the cation fac-[Tc(HO)(CO)] has been studied as a new strategy to bind biomolecules to this radionuclide for preparing radiopharmaceuticals with high molar activity. All complexes were obtained in high yields by heating at moderate temperatures and without subsequent purification. The chemical identity was ascertained by HPLC comparison with the homologous rhenium complexes. Stability studies in cysteine solution and serum have shown a good stability of the coordination set fac-[Tc(CO)(SS)(P)]. Preliminary biological studies of the radiocomplex functionalized with D-(+)-glucosamine with carcinoma cells have been performed

The structure of dichlorobis[μ-(3-dimethylamino-1-propanethiolato)-μ-S,N]-dipalladium(II), (I) [Pd2(C5H12NS)2Cl2], and ac,bd,eg, fh-tetrakis[μ-(3-piperidinemethanethiolato)-μ-S,N]-tripalladium(II) dichloride dihydrate, (II) [Pd3(C6H12NS)4]Cl2.2H2O

Mr=520.15, monoclinic, P21/n, a=7.207(2), B=20.616(4), c=5.854(1) A, β=96.05(1)º, V=864.9(6)A3, Z=2, Dx=2.00 Mg m-3, Mo Ka, = 0.71069 A, µ=2.553 mm-1, F(000)=512, 298 K, R=0.060 for 1492 reflections. (II): Mr=947.07, triclinic, Pl, a=12.666(7), b=10.595(6), c=6.572(5)A, a=98.30(2), = 97.04(2), = 99.84(2)º, V=850(2)A3, Z=1, Dx=1.85 Mg m-3, Mo Ka, =0.71069 A, µ=1.958 mm-1, F(000)=490, 298 K, R=0.071 for 1879 reflections. (I) was solved by direct methods, using MULTAN and DIRDIF, (II) by the heavy-atom method. The four-membered Pd, S, Pd, S rings have a syn-exo conformation, with dihedral angles between the S, Pd, S planes of 154.4(2) and 133.0(3)º for (I) and (II), respectively

New bioconjugated rhenium carbonyls by transmetalation reaction with zinc derivatives

The transmetallation reaction between zinc dithiocarbamates and rhenium carbonyls has been used as a new strategy to link biomolecules to transition metals. The zinc(II) dithiocarbamate of isonipecotic acid (1) and the succinimidyl ester derivative (2) were prepared by straight forward procedures and were fully characterized by spectroscopic and X-ray diffraction methods, showing in both cases the presence of dinuclear complexes. Complex 2 reacted with all the primary and secondary amines studied (glycine methyl ester, β-alanine methyl ester, 1-(2-methoxyphenyl)piperazine and D-(+)-glucosamine) through the activated succinimidyl ester group, linking the metallic fragment with the biomolecule by the formation of a peptidic bond, and leading to the respective bioconjugated zinc complexes 3-6. In all cases, these zinc complexes could be isolated from the reaction medium by simple precipitation. These results evidence the potential of complex 2 to be used as a synthon to link the zinc dithiocarbamate fragment to biomolecules that contain an amine group. Complexes 3-6 were characterized by the usual spectroscopic methods and all data agree with the proposed structures, which do not contain significant interactions between the zinc fragment and the functional groups of these biomolecules. The transmetallation reaction between the zinc complexes 3-6 and the rhenium carbonyl [ReBr₃(CO)₃]²⁻ led to the expected rhenium dithiocarbamates 7-10 with no change in the organic dithiocarbamate fragments, confirming the viability of this reaction as a tool for linking biomolecules to transition elements. All complexes were characterized by spectroscopic methods and the crystal structure of 8 was studied by X-ray diffraction analysis. All data demonstrated that the biomolecule is positioned far away from the fac-{Re(CO)₃} fragment and the octahedral coordination around the metal is completed by the functionalized dithiocarbamate and a phosphine ligand. Finally, the analysis by ESI-MS spectrometry of the reaction between the zinc complex 4 and a water solution of [Re(H₂O)₃(CO)₃]+ at a very low concentration (10 ppm) showed that the transmetallation reaction took place even though the solubility of the zinc complex in water medium was as low as 0.66 ppm. This preliminary result supports the viability of this approach for the preparation of rhenium and technetium target specific radiopharmaceuticals since the preparation of these compounds are always performed in water medium

Supramolecular arrangement of molybdenum carbonyl metallosurfactants with CO-releasing properties

Two families of molybdenum carbonyl metallosurfactants, Mo(CO)₅L and Mo(CO)₄L₂, were synthesized using the functionalized phosphines, Ph₂P(CH₂)nSO₃Na (n = 2, 6, 10) and characterized by the usual spectroscopic and spectrometric methods. The study of the supramolecular arrangements of these compounds in aqueous medium has been performed by surface tension, fluorescence, dynamic light scattering, cryo-TEM, and small angle X-ray scattering. All data points to the formation of medium and large vesicular structures with a membrane similar to the classical lipid bilayer, but it contains organometallic fragments instead of simple hydrophobic chains. Studies of CO releasing with these molybdenum carbonyl metallosurfactants have shown their viability as a promising CO releasing molecules