Sinfonia IV : Kesäsinfonia

Soitinnus: orkesteri.

Triggering the generation of an iron(IV)-oxo compound and its reactivity toward sulfides by RuII photocatalysis

The preparation of [FeIV(O)(MePy2tacn)]2+ (2, MePy2tacn = N-methyl-N,N-bis(2-picolyl)-1,4,7-triazacyclononane) by reaction of [FeII(MePy2tacn)(solvent)]2+ (1) and PhIO in CH3CN and its full characterization are described. This compound can also be prepared photochemically from its iron(II) precursor by irradiation at 447 nm in the presence of catalytic amounts of [Ru II(bpy)3]2+ as photosensitizer and a sacrificial electron acceptor (Na2S2O8). Remarkably, the rate of the reaction of the photochemically prepared compound 2 toward sulfides increases 150-fold under irradiation, and 2 is partially regenerated after the sulfide has been consumed; hence, the process can be repeated several times. The origin of this rate enhancement has been established by studying the reaction of chemically generated compound 2 with sulfides under different conditions, which demonstrated that both light and [Ru II(bpy)3]2+ are necessary for the observed increase in the reaction rate. A combination of nanosecond time-resolved absorption spectroscopy with laser pulse excitation and other mechanistic studies has led to the conclusion that an electron transfer mechanism is the most plausible explanation for the observed rate enhancement. According to this mechanism, the in-situ-generated [RuIII(bpy)3] 3+ oxidizes the sulfide to form the corresponding radical cation, which is eventually oxidized by 2 to the corresponding sulfoxide

Lesões em DNA induzidas pela autoxidação de S(IV) na presença de íons metálicos de transição

The oxidation of sulfite catalyzed by transition metal ions produces reactive oxysulfur species that can damage plasmid and isolated DNA in vitro. Among the four DNA bases, guanine is the most sensitive to one-electron oxidation promoted by the species formed in the autoxidation of sulfite (HSO5-, HO•, SO3•-, SO4•- and SO5•-) due to its low reduction potential and ability to bind transition metal ions capable to catalyze oxidative processes. Some oxidative DNA lesions are promutagenic and oxidative DNA damage is proposed to play a crucial role in certain human pathologies, including cancer.

Síntese e caracterização de um novo complexo de platina (IV) a partir de seu análogo de platina (II) utilizando iodo molecular como agente oxidante: uma rota sintética interessante para obtenção de novos complexos de platina

In an attempt to reduce toxicity and widen the spectrum of activity of cisplatin and its analogues, much attention has been focused on designing new platinum complexes. This work reports the synthesis and characterization of novel compounds of the platinum (II) and platinum (IV) containing 2-furoic hydrazide acid and iodide as ligands. Although the prepared compounds do not present the classical structure of biologically active platinum analogues, they could be potentially active or useful as precursors to prepare antitumor platinum complexes. The reported compounds were characterized by ¹H NMR, 13C NMR, 195Pt NMR, IR and elemental analyses.

Legend IV

Soitinnus: piano.

Entrevista con Manuel Villegas sobre 'El error de Prometeo. Psico(pato)logía del desarrollo moral'

Entrevista con Manuel Villegas

Arabescata : Sinfonia IV

Digitoitu 28. 9. 2007.

La educación moral en la enseñanza obligatoria

Quien lea este libro, desde la introducción a las notas o quien conozca la trayectoria y ciertas publicaciones anteriores de su autor, sabrá que esta recensión ha sido escrita desde un lugar en el que la neutralidad y la imparcialidad resultan del todo improbables. La obra de Josep M.ª Puig objeto de la presente reseña tiene como referencia y marco de reflexión fundamentales los trabajos previos del GREM (Grup de Recerca en Educació Moral de la Universitat de Barcelona), equipo del que también forma parte el autor de esta reseña. Resulta asimismo que el autor de estas líneas hace más de veinte años que es amigo y colega del autor del libro. Y que, por si fuera poco, el autor del libro reconoce en su introducción una supuesta 'deuda especial' con el autor de la reseña. Con tales antecedentes, la credibilidad de esta recensión ha de quedar irremediablemente bajo mínimos. Por esta razón, voy a limitarme a señalar los defectos principales que a mi modo de ver tiene la obra.

Stereoselective syntheses of (+)- isoretronecanol and (+)-5-epi-tashiromine via addition of chiral titanium (iv) enolates to cyclic n-acyliminium ions

The stereoselective addition of the titanium (IV) enolates derived from (S)-4-isopropyl-N-4-chlorobutyryl-1,3-thiazolidine-2-thione (8) and from (S)-4-isopropyl-N-4-chloropentanoyl-1,3-thiazolidine-2-thione (9) to N-Boc-2-methoxypyrrolidine (5b) afforded the addition products (+)-10 and (+)-11 in 84% yield in both cases, as 8.6:1 and 10:1 diastereoisomeric mixtures, respectively. A three-step sequence allowed to convert these adducts to (+)-isoretronecanol (1) and (+)-5-epi-tashiromine (2) in 43% and 49% overall yield, respectively.

Ètica per aixecar la Moral : Problemes ètics als serveis socials bàsics en temps de crisi

Els riscos ètics als serveis socials en temps de crisi es multipliquen i s’intensifiquen, però en essència no es tracta de riscos nous ni diferents dels que es podien produir en temps de bonança econòmica i social. No obstant, la cruesa del context dels serveis socials bàsics (freqüència de les situacions límit que s'han d'atendre, les qüestions internes i externes de la pràctica professional, el malestar i desencant dels professionals) pot suposar una oportunitat de visibilitat i prendre consciència d'aquests riscos ètics. A la vegada, l'anàlisi i l'abordatge d'aquest nou context des d'una perspectiva ètica pot suposar un antídot que permeti ressituar la pràctica professional (amb els seus límits, però també amb les seves possibilitats), millorar-ne la qualitat i la transparència, i, de retruc, trencar amb la dinàmica de cronificació de la insatisfacció i queixa professional. És a dir, la perspectiva ètica pot ajudar a aixecar la moral dels professionals. Així doncs, amb aquesta recerca pretenem assolir els següents objectius: Identificar els riscos ètics de la intervenció als serveis socials bàsics en relació als efectes i l'impacte de la crisi econòmica; analitzar els diferents riscos ètics identificats i efectuar propostes d'abordatge i minimització d'aquests riscos ètics

Extração líquido-líquido de ferro(III) e titânio(IV) pelo ácido bis-(2-etil-hexil) fosfórico (D2EHPA) em meio de ácido sulfúrico

This work presents a study on the separation of Fe(III) and Ti(IV) from sulfuric acid leaching solutions of ilmenite (FeTiO3) using liquid-liquid extraction with D2EHPA in n-dodecane as extracting agent. The distribution coefficients (K D) of the elements related to free acidity and concentration of Fe(III) and Ti(IV) were determined. Free acidity was changed from 3x10-2 to 11.88 mol L-1 and D2EHPA concentration was fixed at 1.5 mol L-1. Recovery of final products as well as recycling of wastes generated in the process were also investigated. The LLE process as a feasible alternative to obtain high-purity TiO2.

Disputatio pro articulo IV. Libri concordiae

Arkit: A-C4.

De sermone Dei epanorthotico ad Cainum Gen. IV:6. 7

Errata.

Termocromismo em soluções de alcóxidos de Vanádio(IV): uma abordagem pela modelagem molecular

The thermochromic behavior exhibited by vanadium(IV) alkoxides, [V2(μ-OPr i)2(OPr i) 6] and [V2(μ-ONep)2(ONep)6 ], OPr i = isopropoxide and ONep = neopentoxide, was studied by molecular modeling using DFT, TDDFT and INDO/S methods. The vibrational and electronic spectra calculated for [V2(μ-OPr i)2(OPr i) 6] were very similar to the experimental data registered for crystalline samples of the complex and for its solutions at low temperature (< 210 K), while spectra recorded at high temperature (> 315 K) were compatible with those calculated for the monomeric form, [V(OPr i)4]. These results consistently point to a monomer/dimer equilibrium as an explanation for the solution thermochromism of {V(OPr i)4}n. In spite of the structural similarity between [V2(μ-ONep)2(ONep)6 ] and [V2(μ-OPr i)2(OPr i) 6] in the solid state, the thermochromic behavior of the former could not be explained by the same model, and the possibility of tetranuclear aggregation at low temperatures was also investigated.

Síntese e caracterização de complexos de platina(IV) com derivados N-benzilados da 1,3-propanodiamina

The present work describes the synthesis of a series of platinum(IV) complexes with N-benzyl 1,3-propanediamine derivatives. Since substitution of the axial ligands in the platinum(IV) complexes may alter their pharmacological properties, we have prepared complexes with different groups, such as hydroxide, chloride and acetate using a sequence of substitution reactions. The resulting complexes were fully characterized by IR, ¹H, 13C and 195Pt NMR spectroscopies, and elemental analysis.