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1.
Chemistry ; 29(5): e202202627, 2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36260535

RESUMO

We report the synthesis and late-stage diversification of a new class of hetero-buckybowl, BN-embedded dibenzocorannulenes (B2 N2 -DBCs). The synthesis is achieved via one-shot halogenative borylation, comprising the nitrogen-directed haloboration of alkyne and an intramolecular bora-Friedel-Crafts reaction, which provides BN-embedded dibenzocorannulene possessing two bromo substituents (B2 N2 -DBC-Br). B2 N2 -DBC-Br undergoes diversification via coupling reactions to provide a variety of arylated derivatives (B2 N2 -DBC-R), exhibiting strong blue fluorescence. An organic light-emitting diode (OLED) employing one of the derivatives as an emitter exhibited a high external quantum efficiency of 6.6 % and long operational lifetime of 907 h at an initial luminance of 1000 cd m-2 , indicating the significant potential for the development of efficient and stable hetero-buckybowl-based OLED materials.


Assuntos
Alcinos , Nitrogênio , Fluorescência
2.
Angew Chem Int Ed Engl ; 60(23): 12835-12840, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33749982

RESUMO

Cationic BN-embedded polycyclic aromatic hydrocarbons (BN-PAH+ s) were synthesized from a nitrogen-containing macrocycle via pyridine-directed tandem C-H borylation. Incorporating BN into PAH+ resulted in a remarkable hypsochromic shift due to an increase in the LUMO energy and the symmetry changes of the HOMO and LUMO. Electrophilic substitution or anion exchange of BN-PAH+ possessing tetrabromoborate as a counter anion (BN+ [BBr4 - ]) afforded air-stable BN-PAH/PAH+ s. Of these, BN+ [TfO- ] allowed reversible two-electron reduction and the formation of two-dimensional brickwork-type π-electronic ion pair with 1,2,3,4,5-pentacyanocyclopentadienyl anion, demonstrating the potential application of BN-PAH+ as electronic materials.

3.
Angew Chem Int Ed Engl ; 60(33): 17910-17914, 2021 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-34038618

RESUMO

Herein, we reported an ultrapure blue multiple-resonance-induced thermally activated delayed fluorescence (MR-TADF) material (ν-DABNA-O-Me) with a high photoluminescence quantum yield and a large rate constant for reverse intersystem crossing. Because of restricted π-conjugation of the HOMO rather than the LUMO induced by oxygen atom incorporation, ν-DABNA-O-Me shows a hypsochromic shift compared to the parent MR-TADF material (ν-DABNA). An organic light-emitting diode based on this material exhibits an emission at 465 nm, with a small full-width at half-maximum of 23 nm and Commission Internationale de l'Eclairage coordinates of (0.13, 0.10), and a high maximum external quantum efficiency of 29.5 %. Moreover, ν-DABNA-O-Me facilitates a drastically improved efficiency roll-off and a device lifetime compared to ν-DABNA, which demonstrates significant potential of the oxygen atom incorporation strategy.

4.
Kekkaku ; 92(1): 11-19, 2017 Jan.
Artigo em Japonês | MEDLINE | ID: mdl-30646468

RESUMO

[Objectives] To investigate the adverse reactions of antimicrobial drugs in multidrug-resistant tuberculosis (MDR-TB) and extensively drug-resistant tuberculosis (XDR- TB) patients. [Results] Sixty-six patients with MDR-TB who have been treated from 2010 through 2014 were evaluated in the retro- spective analysis. Variety of adverse reactions including psychological reaction, central nervous system toxicity, ophthalmic toxicity, peripheral neurotoxicity, gastrointestinal reactions, hematologic abnormalities, musculoskeletal adverse effects, and endocrine disorder, were observed. However, there was no fatal case due to the adverse reactions of the anti-tubercu- losis drugs in this observation. [Conclusions] Drugs for MDR-TB and XDR-TB treatment are limited and the adverse reactions of drugs for MDR-TB and XDR-TB are not well-known. Therefore, the treatment may fail due to inappropriate management of adverse events. MDR-TB and XDR-TB should be treated by the experts of the adverse reactions of all anti-tuberculosis drugs.


Assuntos
Antituberculosos/efeitos adversos , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antituberculosos/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Adulto Jovem
5.
Angew Chem Int Ed Engl ; 56(18): 5087-5090, 2017 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-28370999

RESUMO

The increasing attention devoted to triangulenes and their heteroatom derivatives inspired us to explore a divergent synthesis of heteroatom-centered 4,8,12-triazatriangulenes, which involved the preparation of a nitrogen-containing macrocyclic precursor and subsequent central heteroatom introduction by electrophilic C-Li and C-H substitution. The boron-centered triangulene has a planar structure unlike the bowl-shaped phosphorus- and silicon-centered triangulenes. The described synthetic procedure can be used to fabricate a broad range of attractive functional materials, for example, for organic light-emitting diodes, based on heteroatom-centered triangulenes.

6.
Kekkaku ; 90(4): 453-6, 2015 Apr.
Artigo em Japonês | MEDLINE | ID: mdl-26489147

RESUMO

BACKGROUND: Mycobacterium kansasii is the second most common nontuberculous mycobacterial pulmonary disease pathogen in Japan. Fibrocavitary disease is characteristic of M. kansasii pulmonary disease in male patients. OBJECTIVE: To clarify the clinico-microbiological characteristics of M. kansasii pulmonary disease in recent years in a Tokyo hospital specializing in mycobacteriosis. METHODS: A retrospective chart review was performed on 77 M. kansasii culture-positive cases from January 2003 to December 2010. Sequence analysis of the hsp65 gene using PCR-restriction enzyme pattern analysis (hsp65-PRA) was used to identify bacterial genotypes. RESULTS: Seventy-four cases fulfilled the diagnostic criteria for inclusion. Female patients comprised 22% of cases (16 cases, 63.2 ± 24.6 years of age) and were older than male patients (58 cases, 55.5 ± 17.5 years of age). Although the peak distribution among men was patients in their 50s, female patients showed a bimodal distribution with increased occurrence in older women. Radiological examination showed that approximately 90% of male and younger female patients had fibrocavitary disease. However, elderly female patients tended to have nodular bronchiectatic disease. Genotype analysis revealed that all bacterial strains from both genders were subtype I. CONCLUSIONS: Compared to previous reports, the number of female patients with M. kansasii pulmonary disease had increased, with an unusual age distribution. These different age-related radiological findings might be due to host factors.


Assuntos
Infecções por Mycobacterium não Tuberculosas/epidemiologia , Mycobacterium kansasii , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Genótipo , Hospitais Especializados , Humanos , Masculino , Pessoa de Meia-Idade , Infecções por Mycobacterium não Tuberculosas/microbiologia , Mycobacterium kansasii/isolamento & purificação , Fatores Sexuais , Tóquio
7.
Kekkaku ; 90(10): 665-70, 2015 Oct.
Artigo em Japonês | MEDLINE | ID: mdl-26821395

RESUMO

OBJECTIVE AND METHODS: We analyzed the clinical effects of treatment for Mycobacterium tuberculosis infection for 1 year in our specialized hospital in 2011. Two hundred and ninety-six (296) patients were admitted and received treatment. RESULTS: Two hundred and fifty-six patients (86.5%) were started on the standard treatment with 3 drugs (isoniazid [INH, rifampicin [RFP], and ethambutol [EB] or streptomycin [SM]) or 4 drugs (INH, RFP, EB or SM, and pyrazinamide [PZA]). One hundred and seventy-one patients (66.8%) continued receiving the standard treatment during the admission period. Of 160 cases who could continue 4 drugs, under 80 year-old patients were 127 cases (76.0%), but over 80 year-old patients were 33 cases (49.3%). The mean duration for negative conversion of sputum culture was 40.6 days. Liver dysfunction due to 4 drugs (INH, RFP, EB, and PZA) was noted in 8.5% of patients. Eighteen of the 296 patients had multi-drug resistant tuberculosis (MDR-TB). Each MDR-TB patient received individualized treatment. Moreover, 7 of the MDR-TB cases were treated surgically. DISCUSSION: Treatment of TB had taken long time, and some patients could not continue the treatment owing to the adverse effects of drugs. Hence, it is important to monitor adverse effects of drugs in each patient.


Assuntos
Antituberculosos/administração & dosagem , Hospitais Especializados/estatística & dados numéricos , Tuberculose/tratamento farmacológico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antituberculosos/efeitos adversos , Antituberculosos/farmacologia , Criança , Farmacorresistência Bacteriana , Farmacorresistência Bacteriana Múltipla , Etambutol , Feminino , Humanos , Isoniazida , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis/efeitos dos fármacos , Pirazinamida , Estudos Retrospectivos , Rifampina , Estreptomicina , Fatores de Tempo , Resultado do Tratamento , Tuberculose/microbiologia , Adulto Jovem
8.
Kekkaku ; 89(11): 797-802, 2014 Nov.
Artigo em Japonês | MEDLINE | ID: mdl-25730947

RESUMO

BACKGROUND: Drugs for tuberculosis and non-tuberculosis mycobacterial diseases are limited. In particular, no new drugs for non-tuberculosis mycobacterial disease have been developed in recent years. Antimycobacterial drugs have many adverse reactions, for which drug desensitization therapy has been used. PURPOSE: Rapid drug desensitization (RDD) therapy, including antituberculosis drugs and clarithromycin, has been implemented in many regions in Europe and the United States. We investigated the validity of RDD therapy in Japan. PATIENTS AND METHOD: We report our experience with RDD therapy in 13 patients who developed severe drug allergy to antimycobacterial treatment. The desensitization protocol reported by Holland and Cernandas was adapted. RESULT: The underlying diseases were 7 cases of pulmonary Mycobacterium avium complex disease and 6 cases of pulmonary tuberculosis. Isoniazid was readministered in 2 (100%) of 2 patients; rifampicin, in 8 (67.7%) of 12 patients; ethambutol, in 4 (67.7%) of 6 patients; and clarithromycin, in 2 (100%) of 2 patients. CONCLUSION: In Japan, the desensitization therapy recommended by the Treatment Committee of the Japanese Society for Tuberculosis have been implemented generally. We think RDD therapy is effective and safe as the other desensitization therapy. We will continue to investigate the efficiency of RDD therapy in patients who had discontinued antimycobacterial treatment because of the drug allergic reaction.


Assuntos
Antibacterianos/efeitos adversos , Dessensibilização Imunológica , Hipersensibilidade a Drogas/terapia , Infecções por Mycobacterium/tratamento farmacológico , Tuberculose/tratamento farmacológico , Antibacterianos/uso terapêutico , Hipersensibilidade a Drogas/imunologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
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