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1.
J Phys Chem Lett ; 14(28): 6486-6493, 2023 Jul 20.
Article in English | MEDLINE | ID: mdl-37439679

ABSTRACT

Understanding the initial growth process during atomic layer deposition (ALD) is essential for various applications employing ultrathin films. This study investigated the initial growth of ALD Ir films using tricarbonyl-(1,2,3-η)-1,2,3-tri(tert-butyl)-cyclopropenyl-iridium and O2. Isolated Ir nanoparticles were formed on the oxide surfaces during the initial growth stage, and their density and size were significantly influenced by the growth temperature and substrate surface, which strongly affected the precursor adsorption and surface diffusion of the adatoms. Higher-density and smaller nanoparticles were formed at high temperatures and on the Al2O3 surface, forming a continuous Ir film with a smaller thickness, resulting in a very smooth surface. These findings suggest that the initial growth behavior of the Ir films affects their surface roughness and continuity and that a comprehensive understanding of this behavior is necessary for the formation of continuous ultrathin metal films.

2.
Chem Commun (Camb) ; 54(20): 2487-2490, 2018 Mar 06.
Article in English | MEDLINE | ID: mdl-29441397

ABSTRACT

We describe herein the synthesis of a Ni(ii) bis(dithiobenzoate)-type complex three-dimensionally insulated by a [1]rotaxane structure to reveal the importance of the insulation. Under cyclic voltammetry conditions, the complex showed a stable and reversible redox behavior in contrast to a non-insulated reference complex, clearly demonstrating the effectiveness of the rotaxane-type insulation as a new method of kinetic metal complex stabilization.

3.
Lancet Oncol ; 15(11): 1236-44, 2014 Oct.
Article in English | MEDLINE | ID: mdl-25175099

ABSTRACT

BACKGROUND: With use of EGFR tyrosine-kinase inhibitor monotherapy for patients with activating EGFR mutation-positive non-small-cell lung cancer (NSCLC), median progression-free survival has been extended to about 12 months. Nevertheless, new strategies are needed to further extend progression-free survival and overall survival with acceptable toxicity and tolerability for this population. We aimed to compare the efficacy and safety of the combination of erlotinib and bevacizumab compared with erlotinib alone in patients with non-squamous NSCLC with activating EGFR mutation-positive disease. METHODS: In this open-label, randomised, multicentre, phase 2 study, patients from 30 centres across Japan with stage IIIB/IV or recurrent non-squamous NSCLC with activating EGFR mutations, Eastern Cooperative Oncology Group performance status 0 or 1, and no previous chemotherapy for advanced disease received erlotinib 150 mg/day plus bevacizumab 15 mg/kg every 3 weeks or erlotinib 150 mg/day monotherapy as a first-line therapy until disease progression or unacceptable toxicity. The primary endpoint was progression-free survival, as determined by an independent review committee. Randomisation was done with a dynamic allocation method, and the analysis used a modified intention-to-treat approach, including all patients who received at least one dose of study treatment and had tumour assessment at least once after randomisation. This study is registered with the Japan Pharmaceutical Information Center, number JapicCTI-111390. FINDINGS: Between Feb 21, 2011, and March 5, 2012, 154 patients were enrolled. 77 were randomly assigned to receive erlotinib and bevacizumab and 77 to erlotinib alone, of whom 75 patients in the erlotinib plus bevacizumab group and 77 in the erlotinib alone group were included in the efficacy analyses. Median progression-free survival was 16·0 months (95% CI 13·9-18·1) with erlotinib plus bevacizumab and 9·7 months (5·7-11·1) with erlotinib alone (hazard ratio 0·54, 95% CI 0·36-0·79; log-rank test p=0·0015). The most common grade 3 or worse adverse events were rash (19 [25%] patients in the erlotinib plus bevacizumab group vs 15 [19%] patients in the erlotinib alone group), hypertension (45 [60%] vs eight [10%]), and proteinuria (six [8%] vs none). Serious adverse events occurred at a similar frequency in both groups (18 [24%] patients in the erlotinib plus bevacizumab group and 19 [25%] patients in the erlotinib alone group). INTERPRETATION: Erlotinib plus bevacizumab combination could be a new first-line regimen in EGFR mutation-positive NSCLC. Further investigation of the regimen is warranted. FUNDING: Chugai Pharmaceutical Co Ltd.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Carcinoma, Non-Small-Cell Lung/drug therapy , ErbB Receptors/drug effects , Lung Neoplasms/drug therapy , Quinazolines/administration & dosage , Aged , Antibodies, Monoclonal, Humanized/administration & dosage , Bevacizumab , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/mortality , Carcinoma, Non-Small-Cell Lung/pathology , Carcinoma, Squamous Cell/drug therapy , Carcinoma, Squamous Cell/genetics , Carcinoma, Squamous Cell/mortality , Carcinoma, Squamous Cell/pathology , Confidence Intervals , Disease-Free Survival , Dose-Response Relationship, Drug , Drug Administration Schedule , ErbB Receptors/genetics , Erlotinib Hydrochloride , Female , Humans , Japan , Kaplan-Meier Estimate , Lung Neoplasms/genetics , Lung Neoplasms/mortality , Lung Neoplasms/pathology , Male , Maximum Tolerated Dose , Middle Aged , Mutation , Neoplasm Invasiveness/pathology , Neoplasm Staging , Prognosis , Survival Analysis , Treatment Outcome
4.
Clin Lung Cancer ; 15(6): 448-54, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25043209

ABSTRACT

INTRODUCTION: Although interstitial lung disease (ILD) is a known serious adverse effect of epidermal growth factor receptor tyrosine kinase inhibitors, the risk factors for its development are poorly defined. To determine the risk factors for the development of drug-induced ILD and poor-prognosis (fatal) drug-induced ILD after erlotinib treatment, we assessed the baseline pulmonary status in patients with non-small cell lung cancer enrolled in a postmarketing clinical study of erlotinib. PATIENTS AND METHODS: In the present prospective cohort study, the baseline pulmonary status of all patients was evaluated using conventional or high-resolution computed tomography. The patients were monitored for the development of drug-induced ILD for 120 days after the start of treatment. All diagnoses of drug-induced ILD were confirmed by an independent ILD safety review committee. The risk factors were determined using logistic regression analysis. RESULTS: A total of 645 patients were enrolled, of whom 627 were evaluable. The committee confirmed the diagnoses of drug-induced ILD in 19 patients, 6 of whom had fatal outcomes. Multivariate logistic regression analysis revealed that pre-existing ILD and limited residual normal lung were significant risk factors for the development of drug-induced ILD. An additional multivariate logistic regression analysis revealed that limited residual normal lung was a significant risk factor for the development of poor-prognosis (fatal) drug-induced ILD. CONCLUSION: Pre-existing ILD and the amount of residual normal lung (≤ 50%) were identified as risk factors for the development of drug-induced ILD. The amount of residual normal lung (≤ 50%) was identified as a risk factor for the development of poor-prognosis (fatal) drug-induced ILD.


Subject(s)
Carcinoma, Non-Small-Cell Lung/drug therapy , Lung Diseases, Interstitial/chemically induced , Lung Diseases, Interstitial/epidemiology , Lung Neoplasms/drug therapy , Protein Kinase Inhibitors/adverse effects , Quinazolines/adverse effects , Cohort Studies , Erlotinib Hydrochloride , Humans , Lung/diagnostic imaging , Lung/drug effects , Lung/pathology , Prospective Studies , Protein Kinase Inhibitors/therapeutic use , Quinazolines/therapeutic use , Risk Factors , Tomography, X-Ray Computed
5.
Chem Commun (Camb) ; 46(18): 3083-5, 2010 May 14.
Article in English | MEDLINE | ID: mdl-20424745

ABSTRACT

This work reports the synthesis and characterization of the first water-soluble iridium porphyrin, iridium(iii) diaqua porphyrin [Ir(III)(TSPP)(OH(2))(2)](3-) (1, TSPP = tetra-p-sulfonatophenyl porphyrin). The structure of 1 was unequivocally determined by single crystal X-ray analysis. Benzo-18-crown-6-ether is essential for producing single crystals suitable for X-ray analysis.

6.
Chemistry ; 13(31): 8714-25, 2007.
Article in English | MEDLINE | ID: mdl-17665374

ABSTRACT

A doubly protonated hydrochloride salt of a saddle-distorted dodecaphenylporphyrin (H2DPP), [H4DPPP]Cl2, forms a porphyrin nanochannel (PNC). X-ray crystallography was used to determine the structure of the molecule, which revealed the inclusion of guest molecules within the PNC. Electron-donating molecules, such as p-hydroquinone and p-xylene, were selectively included within the PNC in sharp contrast to electron acceptors, such as the corresponding quinones, which were not encapsulated. This result indicates that the PNC can recognize the electronic character and steric hindrance of the guest molecules during the course of inclusion. ESR measurements (photoirradiation at lambda>340 nm at room temperature) of the PNC that contains p-hydroquinone, catechol, and tetrafluorohydroquinone guest molecules gave well-resolved signals, which were assigned to cation radicals formed without deprotonation based on results from computer simulations of the ESR spectra and density functional theory (DFT) calculations. The radicals are derived from photoinduced electron transfer from the guest molecules to the singlet state of H4DPP2+. Transient absorption spectroscopy by femtosecond laser flash photolysis allowed us to observe the formation of 1(H4DPP2+)*, which is converted to H4DPP+. by electron transfer from the guest molecules to 1(H4DPP2+)*, followed by fast disproportionation of H4DPP+., and charge recombination to give diamagnetic species and the triplet excited state 3(H4DPP2+)*, respectively.


Subject(s)
Electrons , Nanostructures/chemistry , Porphyrins/chemistry , Cations/chemistry , Crystallography, X-Ray , Electrochemistry , Electron Spin Resonance Spectroscopy/methods , Models, Chemical , Models, Molecular , Molecular Structure , Photochemistry , Temperature
7.
Science ; 316(5824): 585-7, 2007 Apr 27.
Article in English | MEDLINE | ID: mdl-17463285

ABSTRACT

Models of the active site in [NiFe]hydrogenase enzymes have proven challenging to prepare. We isolated a paramagnetic dinuclear nickel-ruthenium complex with a bridging hydrido ligand from the heterolytic cleavage of H2 by a dinuclear NiRu aqua complex in water under ambient conditions (20 degrees C and 1 atmosphere pressure). The structure of the hexacoordinate Ni(mu-H)Ru complex was unequivocally determined by neutron diffraction analysis, and it comes closest to an effective analog for the core structure of the proposed active form of the enzyme.


Subject(s)
Hydrogen/chemistry , Hydrogenase/chemistry , Iron/chemistry , Nickel/chemistry , Organometallic Compounds/chemistry , Ruthenium/chemistry , Binding Sites , Biomimetics , Catalysis , Crystallization , Crystallography, X-Ray , Hydrogenase/metabolism , Ligands , Magnetic Resonance Spectroscopy , Molecular Mimicry , Neutron Diffraction , Organometallic Compounds/chemical synthesis , Spectrometry, Mass, Electrospray Ionization , Spectrophotometry, Infrared
8.
Dalton Trans ; (39): 4657-63, 2006 Oct 21.
Article in English | MEDLINE | ID: mdl-17028673

ABSTRACT

Ruthenium aqua complexes [(eta(6)-C(6)Me(6))Ru(II)(L)(OH(2))](2+) {L = bpy (1) and 4,4'-OMe-bpy (2), bpy = 2,2'-bipyridine, 4,4'-OMe-bpy = 4,4'-dimethoxy-2,2'-bipyridine} and iridium aqua complexes [Cp*Ir(III)(L)(OH(2))](2+) {Cp* = eta(5)-C(5)Me(5), L = bpy (5) and 4,4'-OMe-bpy (6)} act as catalysts for hydrogenation of CO(2) into HCOOH at pH 3.0 in H(2)O. The active hydride catalysts cannot be observed in the hydrogenation of CO(2) with the ruthenium complexes, whereas the active hydride catalysts, [Cp*Ir(III)(L)(H)](+) {L = bpy (7) and 4,4'-OMe-bpy (8)}, have successfully been isolated after the hydrogenation of CO(2) with the iridium complexes. The key to the success of the isolation of the active hydride catalysts is the change in the rate-determining step in the catalytic hydrogenation of CO(2) from the formation of the active hydride catalysts, [(eta(6)-C(6)Me(6))Ru(II)(L)(H)](+), to the reactions of [Cp*Ir(III)(L)(H)](+) with CO(2), as indicated by the kinetic studies.

9.
Chem Commun (Camb) ; (6): 716-8, 2005 Feb 14.
Article in English | MEDLINE | ID: mdl-15685314

ABSTRACT

A highly saddle-distorted dodecaphenylporphyrin dication (H4DPP2+) was revealed by X-ray crystallography to form positively charged porphyrin nanochannels which were 1 nm in diameter; chloride anion and redox-active hydroquinone could be incorporated in the channels.


Subject(s)
Cations/chemistry , Ion Channels/chemistry , Porphyrins/chemistry , Chlorides/chemistry , Crystallography, X-Ray , Hydroquinones/chemistry , Models, Molecular , Molecular Conformation , Nanostructures , Oxidation-Reduction , Protons
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