Chiral macrocyclic terpyridine complexes

The syntheses of novel chiral M( II ) bis(terpyridine) cage complexes Fe(L1) 2 -c and Ru(L1) 2 -c are described. The extraordinary design of the precursors Fe(L1) 2 and Ru(L1) 2 allows perfect preorganization for the final closing step. Due to the rigidity of the spacers between the two terpyridine moieties, the two isolated enantiomers barely racemize at room temperature in solution. The stable and axially chiral bis(terpyridine) Fe( II ) and Ru( II ) complexes were fully characterized by NMR-spectroscopy, UV-Vis spectroscopy, electrochemical measurements, high resolution mass spectrometry, circular dichroism measurements, and X-ray structural analysis

Cidofovir for BK Virus-Associated Hemorrhagic Cystitis: A Retrospective Study

Background.BK virus-associated hemorrhagic cystitis (BKV-HC) is a severe complication after allogeneic hematopoietic stem cell transplantation (HSCT), but antiviral treatment for this condition has not been evaluated. Methods.We conducted a retrospective survey on the safety and outcome of cidofovir treatment for patients with BKV-HC in centers affiliated with the European Group for Blood and Marrow Transplantation. Results.From 1 April 2004 to 31 December 2007, 62 patients received a diagnosis of BKV-HC after a median interval of 35 days after HSCT (range, 3-577 days). Fifty-seven patients (92%) received intravenous cidofovir, whereas 5 patients received cidofovir intravesically. Complete response (CR) was recorded in 38 (67%) of 57 patients with HC treated with intravenous cidofovir, whereas partial response (PR) was documented in 7 patients (12%). CR was documented in 3 patients and PR in 1 patient with HC treated with intravesical cidofovir. A reduction of 1-3 logs in BKV load was documented in 8 of the 10 patients achieving CR. Mild-to-moderate toxic effects were recorded in 18 of 57 patients who received intravenous cidofovir administration. In a multivariate analysis, the factors significantly associated with response to cidofovir were the stem cell source (P=.01) and the use of total body irradiation (P=.03). After a median follow-up of 287 days, overall survival and total treatment-related mortality rates were 63% and 40% for patients achieving CR, compared with 14% and 72% for patients with PR or no response to cidofovir, respectively (P<.001 and P=.001, respectively). Conclusions.Cidofovir may be a potentially effective therapy for BKV-HC, but evidence supporting its use requires randomized controlled trial

Characterization and Reactivity Studies of Dinuclear Iridium Hydride Complexes Prepared from Iridium Catalysts with N,P and C,N Ligands Under Hydrogenation Conditions

The dinuclear iridium hydride complexes [IrH(CH3CN)(L1)(μ-H)]2(BArF)2 (7; L1 = (S)-2-(2-((diphenylphosphanyl)oxy)propan-2-yl)-4-isopropyl-4,5-dihydrooxazole, BArF = tetrakis[3,5-bis(trifluoromethyl)phenyl]borate), [IrH(CH2Cl2)(L1)(μ-H)]2(BArF)2 (8), [IrH(L2)(μ-H)]2(BArF)2 (9a; L2 = (S)-1-[2-(2-adamantan-2-yl-4,5-dihydrooxazol-4-yl)-ethyl]-3-(2,6-diisopropylphenyl)-1,2-dihydroimidazol-2-ylidene), and [IrH(L3)(μ-H)]2(BArF)2 (9b; L3 = (S)-1-[2-(2-tert-butyl-4,5-dihydrooxazol-4-yl)-ethyl]-3-(2,6-diisopropylphenyl)-1,2-dihydroimidazol-2-ylidene) were prepared from the corresponding mononuclear [Ir(COD)(L)]BArF precursors by treatment with H2 and characterized by 2D NMR spectroscopy and X-ray diffraction. Conversion to a trinuclear iridium hydride complex, which is usually observed for N,P iridium hydride complexes, is inhibited by addition of 0.5 equiv of [H(OEt2)2]BArF or acetonitrile. Reactions with acetonitrile or 6,6′-bi-2-picoline afforded the mononuclear iridium dihydride complexes [Ir(H)2(CH3CN)2(L1)]BArF (5), [Ir(H)2(CH3CN)2(L3)]BArF (10), or [Ir(H)2(6,6′-bi-2-picoline)(L3)]BArF (11). The CH3CN complexes 7 and 10 are inactive as hydrogenation catalysts. In contrast, the coordinatively unsaturated dinuclear complexes 9a and 9b are active catalysts for the hydrogenation of (E)-1,2-diphenyl-1-propene at 50 bar hydrogen pressure

IHS Book Talk: Hungry for Revolution: The Politics of Food and the Making of Modern Chile

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Convergent Digital Infrastructures and the Role of (Net-)Neutrality

The integration of modern information and communication technologies (ICT) triggers an evolutionary process from previous analog towards convergent digital infrastructures that are the basis for new, cross-domain services and applications. The implementation, however, poses new requirements and regulatory challenges. Among these, a broader view on net neutrality appears to be a crucial precondition that exceeds the single focus on the non-discriminatory transmission of data via the proprietary telecommunication infrastructures of different network operators as critical gatekeepers. Rather, a new, systemic way of thinking in digital infrastructures is necessary. Hereby, the scope of neutrality expands to different functions on several levels of interconnected infrastructures in order to design interoperable systems as platforms for futureorientated, cross-domain services. To adequately describe and comprehend the trajectory from previous analog to convergent digital infrastructures that allow novel services via specific platforms and facilitate an interaction across various domains and industries, we introduce and illustrate distinctive evolutionary steps that reflect different levels of convergence. Since the complex interrelationships and interdependencies within convergent digital infrastructures cannot be readily analyzed in a holistic manner, this paper focuses on the mobility domain as primarily field of analysis. For the examination of digital mobility infrastructures in the context of neutrality, a case study-orientated approach has been developed that divides the field of analysis into three predefined levels and allows an investigation of the specific requirements to implement such convergent infrastructures from a technology-, data- and service-specific perspective. Based on this analysis, we define distinctive extensions to the existing view on net neutrality and, thereby, contribute to the already existing claims in academic literature for the conception of a more holistic view on this topic

Characterization and Reactivity Studies of Dinuclear Iridium Hydride Complexes Prepared from Iridium Catalysts with N,P and C,N Ligands under Hydrogenation Conditions

The dinuclear iridium hydride complexes [IrH­(CH₃CN)­(L1)­(μ-H)]₂­(BAr_F)₂ (<b>7</b>; L1 = (<i>S</i>)-2-(2-((di­phenyl­phos­phanyl)­oxy)­propan-2-yl)-4-isopropyl-4,5-dihydrooxazole, BAr_F = tetrakis­[3,5-bis­(tri­fluoro­methyl)­phenyl]­borate), [IrH­(CH₂Cl₂)­(L1)­(μ-H)]₂­(BAr_F)₂ (<b>8</b>), [IrH­(L2)­(μ-H)]₂­(BAr_F)₂ (<b>9a</b>; L2 = (<i>S</i>)-1-[2-(2-adamantan-2-yl-4,5-dihydro­oxazol-4-yl)-ethyl]-3-(2,6-diiso­propyl­phenyl)-1,2-dihydroimidazol-2-ylidene), and [IrH­(L3)­(μ-H)]₂­(BAr_F)₂ (<b>9b</b>; L3 = (<i>S</i>)-1-[2-(2-<i>tert</i>-butyl-4,5-dihydrooxazol-4-yl)-ethyl]-3-(2,6-diiso­propyl­phenyl)-1,2-dihydro­imidazol-2-ylidene) were prepared from the corresponding mononuclear [Ir­(COD)­(L)]­BAr_F precursors by treatment with H₂ and characterized by 2D NMR spectroscopy and X-ray diffraction. Conversion to a trinuclear iridium hydride complex, which is usually observed for N,P iridium hydride complexes, is inhibited by addition of 0.5 equiv of [H­(OEt₂)₂]­BAr_F or acetonitrile. Reactions with acetonitrile or 6,6′-bi-2-picoline afforded the mononuclear iridium dihydride complexes [Ir­(H)₂­(CH₃­CN)₂­(L1)]­BAr_F (<b>5</b>), [Ir­(H)₂­(CH₃­CN)₂­(L3)]­BAr_F (<b>10</b>), or [Ir­(H)₂­(6,6′-bi-2-picoline)­(L3)]­BAr_F (<b>11</b>). The CH₃CN complexes <b>7</b> and <b>10</b> are inactive as hydrogenation catalysts. In contrast, the coordinatively unsaturated dinuclear complexes <b>9a</b> and <b>9b</b> are active catalysts for the hydrogenation of (<i>E</i>)-1,2-diphenyl-1-propene at 50 bar hydrogen pressure

Chiral boron-bridged bisoxazoline (Borabox) ligands: structures and reactivities of Pd and Cu complexes

Anionic boron-bridged bisoxazolines (borabox ligands) have been synthesized and characterized in their protonated forms. The ligands are tuneable over a wide range, allowing either alkyl or aryl substituents at the oxazoline rings and the central bridging boron atom. The structural parameters of this new ligand type have been investigated by X-ray analyses of palladium and copper complexes. Electronic properties have been studied by 13C NMR spectroscopy and by DFT calculations on palladium allyl complexes and compared to those of analogous bisoxazoline (box) complexes. Borabox complexes are more electron-rich at the metal center than their neutral box congeners, and as a consequence of the longer bonds between the bridging atom and the oxazoline rings, their bite angles are larger. Palladium(II) complexes bearing an unsubstituted allyl ligand and homoleptic copper(II) complexes each possess an almost flat chelate ring. NMR analysis of a (1,3-diphenylallyl)(borabox)palladium complex showed a 92:8 mixture of (syn,syn) and (anti,syn) allyl isomers, in contrast with a previously reported box analogue that existed exclusively in the (syn,syn) form. Comparison of the corresponding crystal structures revealed that the distance between the bisoxazoline and the allyl ligand in the borabox complex is shorter. In the copper-catalyzed allylic oxidation of cyclohexene and cyclopentene with tert-butyl perbenzoate, borabox ligands gave results similar - and in some cases superior - to those obtained with analogous box ligands

Infectious diseases in allogeneic haematopoietic stem cell transplantation: prevention and prophylaxis strategy guidelines 2016

Infectious complications after allogeneic haematopoietic stem cell transplantation (allo-HCT) remain a clinical challenge. This is a guideline provided by the AGIHO (Infectious Diseases Working Group) of the DGHO (German Society for Hematology and Medical Oncology). A core group of experts prepared a preliminary guideline, which was discussed, reviewed, and approved by the entire working group. The guideline provides clinical recommendations for the preventive management including prophylactic treatment of viral, bacterial, parasitic, and fungal diseases. The guideline focuses on antimicrobial agents but includes recommendations on the use of vaccinations. This is the updated version of the AGHIO guideline in the field of allogeneic haematopoietic stem cell transplantation utilizing methods according to evidence-based medicine criteria