Cyclam κ4 To κ3 Ligand Denticity Change Upon Mono-n-substitution With A Carboxypropyl Pendant Arm In A Ruthenium Nitrosyl Complex

The complex fac-[Ru(NO)Cl2(κ3N 4,N8,N11(1-carboxypropyl)cyclam)] Cl·H2O (1-carboxypropyl)cyclam = 3-(1,4,8,11- tetraazacyclotetradecan-1-yl)propionic acid) was prepared in a one pot reaction by mixing equimolar amounts of RuNOCl3 and (1-carboxypropyl)cyclam and was characterized by X-ray crystallography, electrospray ionization tandem mass spectrometry (ESI-MS/MS), elemental analysis, NMR, and electronic and vibrational (IR) spectroscopies. fac-[Ru(NO)Cl2(κ 3N4,N8,N11(1-carboxypropyl)cyclam)] Cl·H2O crystallizes in the triclinic, space group P1, No. 2, with unit cell parameters of a = 8.501(1) Å, b = 9.157(1) Å, c = 14.200(1) Å, α = 72.564(5)°, β = 82.512(5)°, γ = 80.308(5)°, and Z = 2. The Ru-N interatomic distance and bond angle in the [Ru-NO] unit are 1.739(2) Å and 167.7(2)°, respectively. ESI-MS/MS shows characteristic dissociation chemistry that initiates by HCl or NO loss. The IR spectrum displays a ν(NO) at 1881 cm-1 indicating a nitrosonium character. 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A pyrazine bis-adduct of a binuclear rhodium(II) carboxylate containing 3,4,5-triethoxybenzoate as the equatorial ligand

The title compound, tetrakis(μ-3,4,5-triethoxybenzoato κ 2 O:O′)bis[(pyrazine-κN)rhodium(II)](Rh-Rh). [Rh 2 (C 13 -H 17 O 5 ) 4 (C 4 H 4 N 2 ) 2 ], crystallizes on an inversion centre in the triclinic space group P1̄. The equatorial carboxylate ligands bridge the two Rh 11 atoms, giving a binuclear lantern-like structure. The pyrazine molecules occupy the two axial coordination sites. The phenyl rings are titled by ca 10° with respect to the attached carboxylate groups. The pyrazine planes have a torsion angle of ca 19° around the Rh-N bond with respect to the plane of the nearer carboxylate group and are not coplanar with the Rh-Rh bond.Fil:Castro, M.A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.Fil:Chaia, Z.D. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.Fil:Cukiernik, F.D. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.Fil:Rusjan, M. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina

New rhenium(V) nitrofuryl semicarbazone complexes. Crystal structure of [ReOCl2(PPh3)(3-(5-Nitrofuryl)acroleine semicarbazone)]

The synthesis and characterization of the first two Re complexes with semicarbazone ligands is presented. Selected ligands are 5-Nitro-2-furaldehyde semicarbazone (Nitrofurazone) (L1) and its derivative 3-(5-Nitrofuryl)acroleine semicarbazone (L2). Complexes of general formula [RevOCl2(PPh3)L], where L = L1 and L2, were prepared in good yields and high purity by reaction of [RevOCl3(PPh3)2] with L in ethanol or methanol solutions. The complexes formula and molecular structures were supported by elemental analyses and electronic, FTIR, 1H, 13C and 31P NMR spectroscopies. In addition, the crystal and molecular structure of [RevOCl2(PPh3)L2] was determined by X-ray diffraction methods. [ReOCl2(PPh3)(3-(5-Nitrofuryl)acroleine semicarbazone)] crystallizes in the space group P-1 with a = 11.2334(2), b = 11.3040(2), c = 12.5040(2) Å, α = 81.861(1), β = 63.555(1), γ = 83.626(1)°, and Z = 2. The Re(V) ion is in a distorted octahedral environment, equatorially coordinated to a deprotonated semicarbazone molecule acting as a bidentate ligand through its carbonylic oxygen and azomethynic nitrogen atoms, to an oxo ligand and a chlorine atom. The six-fold coordination is completed by another chlorine atom and a triphenylphosphine ligand at the axial positions.Fil: Otero, L.. Universidad de la República Facultad de Química; UruguayFil: Noblia, P.. Universidad de la República Facultad de Química; UruguayFil: Gambino, D.. Universidad de la República Facultad de Química; UruguayFil: Cerecetto, H.. Universidad de la República Facultad de Química; UruguayFil: González, M.. Universidad de la República Facultad de Química; UruguayFil: Sánchez-Delgado, R.. Instituto Venezolano de Investigaciones Científicas; VenezuelaFil: Castellano, E.E.. Universidade de Sao Paulo; BrasilFil: Piro, Oscar Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física La Plata; Argentin

A liquid crystal derived from ruthenium(II,III) and a long-chain carboxylate

The title compound, catena-poly[[tetrakis(μ-decanoato- κ2O:O′)-diruthenium(II,III) (Ru - Ru)]- μ-octanesulfonato-κ2O:O′], [Ru2(C10H19O2)4 (C8H17O3S)], is an octanesulfonate derivative of the mixed-valence complex diruthenium tetradecanoate. The equatorial carboxylate ligands are bidentate, bridging two Ru atoms to form a dinuclear structure. Each of the two independent dinuclear metal complexes in the asymmetric unit is located at an inversion centre. The octanesulfonate anion bridges the two dinuclear units through axial coordination. The alkyl chains of the carboxylate and sulfonate ligands are arranged in a parallel manner. The global structure can be seen as infinite chains of polar moieties separated by a double layer of non-polar alkyl groups, without interdigitation of the alkyl chains.Fil:Zelcer, A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.Fil:Chaia, Z.D. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.Fil:Cukiernik, F.D. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina

A pyrazine bis-adduct of a binuclear rhodium(II) carboxylate containing 3,4,5-triethoxybenzoate as the equatorial ligand

The title compound, tetrakis(μ-3,4,5-triethoxybenzoato κ2O:O′)bis[(pyrazine-κN)rhodium(II)](Rh-Rh). [Rh2(C13-H17O5)4 (C4H4N2)2], crystallizes on an inversion centre in the triclinic space group P1̄. The equatorial carboxylate ligands bridge the two Rh11 atoms, giving a binuclear lantern-like structure. The pyrazine molecules occupy the two axial coordination sites. The phenyl rings are titled by ca 10° with respect to the attached carboxylate groups. The pyrazine planes have a torsion angle of ca 19° around the Rh-N bond with respect to the plane of the nearer carboxylate group and are not coplanar with the Rh-Rh bond.Fil:Castro, M.A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.Fil:Chaia, Z.D. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.Fil:Cukiernik, F.D. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.Fil:Rusjan, M. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina

Atezolizumab versus chemotherapy in patients with platinum-treated locally advanced or metastatic urothelial carcinoma (IMvigor211): a multicentre, open-label, phase 3 randomised controlled trial

Background: Few options exist for patients with locally advanced or metastatic urothelial carcinoma after progression with platinum-based chemotherapy. We aimed to assess the safety and efficacy of atezolizumab (anti-programmed death-ligand 1 [PD-L1]) versus chemotherapy in this patient population. Methods: We conducted this multicentre, open-label, phase 3 randomised controlled trial (IMvigor211) at 217 academic medical centres and community oncology practices mainly in Europe, North America, and the Asia-Pacific region. Patients (aged ≥18 years) with metastatic urothelial carcinoma who had progressed after platinum-based chemotherapy were randomly assigned (1:1), via an interactive voice and web response system with a permuted block design (block size of four), to receive atezolizumab 1200 mg or chemotherapy (physician's choice: vinflunine 320 mg/m2, paclitaxel 175 mg/m2, or 75 mg/m2 docetaxel) intravenously every 3 weeks. Randomisation was stratified by PD-L1 expression (expression on <1% [IC0] or 1% to <5% [IC1] of tumour-infiltrating immune cells vs ≥5% of tumour-infiltrating immune cells [IC2/3]), chemotherapy type (vinflunine vs taxanes), liver metastases (yes vs no), and number of prognostic factors (none vs one, two, or three). Patients and investigators were aware of group allocation. Patients, investigators, and the sponsor were masked to PD-L1 expression status. The primary endpoint of overall survival was tested hierarchically in prespecified populations: IC2/3, followed by IC1/2/3, followed by the intention-to-treat population. This study, which is ongoing but not recruiting participants, is registered with ClinicalTrials.gov, number NCT02302807. Findings: Between Jan 13, 2015, and Feb 15, 2016, we randomly assigned 931 patients from 198 sites to receive atezolizumab (n=467) or chemotherapy (n=464). In the IC2/3 population (n=234), overall survival did not differ significantly between patients in the atezolizumab group and those in the chemotherapy group (median 11·1 months [95% CI 8·6–15·5; n=116] vs 10·6 months [8·4–12·2; n=118]; stratified hazard ratio [HR] 0·87, 95% CI 0·63–1·21; p=0·41), thus precluding further formal statistical analysis. Confirmed objective response rates were similar between treatment groups in the IC2/3 population: 26 (23%) of 113 evaluable patients had an objective response in the atezolizumab group compared with 25 (22%) of 116 patients in the chemotherapy group. Duration of response was numerically longer in the atezolizumab group than in the chemotherapy group (median 15·9 months [95% CI 10·4 to not estimable] vs 8·3 months [5·6–13·2]; HR 0·57, 95% CI 0·26–1·26). In the intention-to-treat population, patients receiving atezolizumab had fewer grade 3–4 treatment-related adverse events than did those receiving chemotherapy (91 [20%] of 459 vs 189 [43%] of 443 patients), and fewer adverse events leading to treatment discontinuation (34 [7%] vs 78 [18%] patients). Interpretation: Atezolizumab was not associated with significantly longer overall survival than chemotherapy in patients with platinum-refractory metastatic urothelial carcinoma overexpressing PD-L1 (IC2/3). However, the safety profile for atezolizumab was favourable compared with chemotherapy, Exploratory analysis of the intention-to-treat population showed well-tolerated, durable responses in line with previous phase 2 data for atezolizumab in this setting. Funding: F Hoffmann-La Roche, Genentech. © 2018 Elsevier Lt