122 research outputs found
フッ素置換遷移金属カルベン錯体を経由する含フッ素化合物の触媒的合成法
科学研究費助成事業 研究成果報告書:挑戦的萌芽研究2016-2017課題番号 : 16K1394
Synthesis of Pinpoint-Fluorinated Polycyclic Aromatic Hydrocarbons: Benzene Ring Extension Cycle Involving Microwave-Assisted SNAr Reaction
Fluoroarenes bearingnoelectron-withdrawing groups (non-activated fluoroarenes) readily underwent nu-cleophilic aromatic substitution with a-cyanocarbanions under microwave irradiation. The sequence (i)formylalkyla-tion involving the cyanoalkylation of fluoroarenes, (ii)di-fluorovinylidenati on, and (iii)Friedel–Crafts-typecycliza-tion, afforded extended fluoroarenes by one benzene ring per cycle. Furthermore, the performance of multiple cyclessuccessfully providedhigher-order pinpoint-fluorinated polycyclic aromatic hydrocarbons (F-PAHs)
Single C−F Bond Activation of the CF3 Group with a Lewis Acid: CF3‐Cyclopropanes as Versatile 4,4‐Difluorohomoallylating Agents
The selective activation of one C−F bond (single activation) of the CF3 group on cyclopropanes was achieved for the first time. When (trifluoromethyl)cyclopropanes were treated with arenes, allylsilanes, silyl enol ethers, or hydrosilanes in the presence of Me2AlCl, fluoride elimination and the subsequent ring opening proceeded to afford 4,4‐difluorohomoallylated products. In the absence of external nucleophiles, an alkyl group of AlR3 was effectively introduced to provide the corresponding 1,1‐difluoroalkenes
Ring-size-selective construction of fluorine-containing carbocycles via intramolecular iodoarylation of 1,1-difluoro-1-alkenes
1,1-Difluoro-1-alkenes bearing a biaryl-2-yl group effectively underwent site-selective intramolecular iodoarylation by the appropriate cationic iodine species. Iodoarylation of 2-(2-aryl-3,3-difluoroallyl)biaryls proceeded via regioselective carbon–carbon bond formation at the carbon atoms in β-position to the fluorine substituents, thereby constructing dibenzo-fused six-membered carbocycles bearing a difluoroiodomethyl group. In contrast, 2-(3,3-difluoroallyl)biaryls underwent a similar cyclization at the α-carbon atoms to afford ring-difluorinated seven-membered carbocycles
コウゴウ ヨウシキ ノ チガイ ガ インプラント チリョウ ケッカ ニ オヨボス エイキョウ : ブンケン コウサツ
Occlusion, including the occlusal scheme, occlusal contact, and occlusal force, has been discussed by many researchers. Traditionally, these arguments have been empirical in clinical experience and not based on scientific evidence.
The aim of this study was to analyze the published literature on clinical follow-up studies focusing on the occlusal scheme of implant treatment. Two databases, “PubMed” and “Japana Centra Revuo Medicina” were searched to retrieve research papers on clinical follow-up studies focusing on the occlusal scheme of implant treatment. Twelve papers were selected from the database using the criteria, and were reviewed. Little scientific evidence supports a relationship between the occlusal scheme and the outcome of osseointegrated implant treatment. Within the limitations of the articles, this review indicates that scientific evidence of occlusal scheme of implant treatment is insufficient. Occlusal scheme has little effect on the survival rate of implants and mutually protected occlusion is used in a fixed superstructure and balanced occlusion is used in a removable superstructure
Flash generation and borylation of 1-(trifluoromethyl)vinyllithium toward synthesis of α-(trifluoromethyl)styrenes
Thermally unstable (3,3,3-trifluoroprop-1-en-2-yl)lithium was generated by lithiation of 2-bromo-3,3,3-trifluoroprop-1-ene and successively underwent borylation in a flow microreactor system. Direct use of the 1-(trifluoromethyl)vinylborate thus formed for the Suzuki–Miyaura coupling in a batch system afforded α-(trifluoromethyl)styrenes in high yields
Feasibility study of two schedules of sunitinib in combination with pemetrexed in patients with advanced solid tumors
Background Sunitinib is an oral multitargeted tyrosine kinase inhibitor of vascular endothelial growth factor and platelet-derived growth factor receptors, as well as of other receptor types. We have performed a feasibility study to investigate the safety of sunitinib in combination with pemetrexed for treatment of advanced refractory solid tumors. Methods Sunitinib was administered once daily on a continuous daily dosing (CDD) schedule (37.5 mg/day) or a 2-weeks-on, 1-week-off treatment schedule (50 mg/day, Schedule 2/1) in combination with pemetrexed at 500 mg/m2 on day 1 of repeated 21-day cycles. Results Twelve patients were enrolled in the study: six on the CDD schedule and six on Schedule 2/1. None of the treated patients experienced a dose-limiting toxicity. Toxicities were manageable and similar in type to those observed in monotherapy studies of sunitinib and pemetrexed. Pharmacokinetic analysis did not reveal any substantial drug–drug interaction. One patient with squamous cell lung cancer showed a partial response and five patients had stable disease. Conclusions Combination therapy with sunitinib administered on Schedule 2/1 (50 mg/day) or a CDD schedule (37.5 mg/day) together with standard-dose pemetrexed (500 mg/m2) was well tolerated in previously treated patients with advanced solid tumors
Nickel-catalyzed [4 + 2] Cycloaddition of Styrenes with Arynes via 1:1 Cross-coupling : Synthesis of 9,10-Dihydrophenanthrenes
The [4 + 2] cycloaddition of styrenes with arynes was achieved via 1:1 cross-coupling by a nickel catalyst. This protocol applies to a variety of styrenes and arynes generated in situ from o-(trimethylsilyl)aryl triflates to afford 9,10-dihydrophenanthrenes involving substituted aromatic rings. By using this method, a naturally occurring stilbenoid is easily synthesized
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