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491.
[reaction: see text]. An N-S acyl-transfer-mediated preparation of peptide thioesters using the S-protected oxazolidinone derived from cysteine has been developed and applied to the synthesis of a 32-mer biologically active peptide by native chemical ligation protocols. 相似文献
492.
Bissel P Geherin S Igarashi K Gandour RD Lazar IM Castagnoli N 《Journal of mass spectrometry : JMS》2006,41(12):1643-1653
Examination of the electrospray ionization product ion spectra of 1,2-dihydropyridinyl and 4-aryl-1,2-dihydropyridinyl derivatives bearing a 1-cyclopropyl or 1-trans-2-phenylcyclopropyl group has led to the characterization of unexpected fragment ions. For example, the base peak at m/z 156 present in the product ion spectrum of trans-1-(2-phenylcyclopropyl)-4-phenyl-1,2-dihydropyridine proved not to be the expected 4-phenylpyridinium species but rather the isomeric 3-phenyl-5-azoniafulvenyl species. The results of studies with a series of structural and isotopically labeled analogs require a novel fragmentation pathway to account for the formation of this and related fragment ions. One possible pathway is based on an initial 1,5-sigmatropic shift of a cyclopropylmethylene hydrogen atom that is accompanied by opening of the cyclopropyl ring. The resulting eniminium intermediates then fragment to yield the 5-azoniafulvenyl species. 相似文献
493.
Takahiro ANDO Takatomo WATANABE Saori MATSUO Tomoki SAMEJIMA Junya YAMAGISHI Takanobu BITO Genki NARUSE Akihiro YOSHIDA Shingo MINATOGUCHI Haruhiko AKIYAMA Kazuhiko NISHIGAKI Shinya MINATOGUCHI Hiroyuki OKURA 《Physical Therapy Research》2022,25(1):18
Objective: To examine the Cardiac Rehabilitation Gifu Network (CR-GNet) feasibility in managing diseases and assisting patients in attaining physical fitness, and its impact on long-term outcomes after acute coronary syndrome (ACS). Methods: In this prospective observational study, we enrolled 47 patients with ACS registered in the CR-GNet between February 2016 and September 2019. 37, 29, and 21 patients underwent follow-up assessments for exercise capacity (peak oxygen uptake) at 3 months, 6 months, and 1 year after discharge, respectively. Major adverse cardiac events (MACE) were compared with controls not registered in the CR-GNet. Results: The coronary risk factors, except blood pressure, improved at 3 and 6 months, and 1 year after discharge. These risk factors in each patient significantly reduced from 2.9 at admission to 1.6, 1.4, and 1.9 at 3 months, 6 months, and 1 year after discharge (p<0.05), respectively. Peak oxygen uptake was significantly higher at 3 months (17.5±4.9 ml/kg/min), 6 months (17.9±5.1 ml/kg/min), and 1 year (17.5±5.5 ml/kg/min) after discharge than that at discharge (14.7±3.6 ml/kg/min) (p<0.05). During follow-up, there was no significant difference; MACE did not occur in any patients in the CR-GNet but occurred in controls. Conclusion: CR-GNet is a feasible option for the long-term management of ACS patients. 相似文献
494.
Yoshiaki Kokubo Itsuki Igarashi Kenichi Nakao Wataru Hachiya Shinichi Kugimiya Tomohiro Ozawa Hideki Masuda Yuji Kajita 《Molecules (Basel, Switzerland)》2022,27(18)
The reactions of newly designed lithiated triamidoamines Li3LR (R = iPr, Pen, and Cy2) with VCl3(THF)3 under N2 yielded dinitrogen–divanadium complexes with a μ-N2 between vanadium atoms [{V(LR)}2(μ-N2)] (R = iPr (1) and Pen (2)) for the former two, while not dinitrogen–divanadium complexes but a mononuclear vanadium complex with a vacant site, [V(LCy2)] (R = Cy2 (3)), were obtained for the third ligand. The V–NN2 and N–N distances were 1.7655(18) and 1.219(4) Å for 1 and 1.7935(14) and 1.226(3) Å for 2, respectively. The ν(14N–14N) stretching vibrations of 1 and 2, as measured using resonance Raman spectroscopy, were detected at 1436 and 1412 cm–1, respectively. Complex 3 reacted with potassium metal in the presence of 18-crown-6-ether under N2 to give a hetero-dinuclear vanadium complex with μ-N2 between vanadium and potassium, [VK(LCy2)(μ-N2)(18-crown-6)] (4). The N–N distance and ν(14N–14N) stretching for 4 were 1.152(3) Å and 1818 cm−1, respectively, suggesting that 4 is more activated than complexes 1 and 2. The complexes 1, 2, 3, and 4 reacted with HOTf and K[C10H8] to give NH3 and N2H4. The yields of NH3 and N2H4 (per V atom) were 47 and 11% for 1, 38 and 16% for 2, 77 and 7% for 3, and 80 and 5% for 4, respectively, and 3 and 4, which have a ligand LCy2, showed higher reactivity than 1 and 2. 相似文献
495.
Optical Review - The development of holographic data storage is expected as a next-generation large-capacity memory. The recording scheme of spatial quadrature amplitude modulated (SQAM) signal,... 相似文献
496.
497.
A stable silagermene, 1,1‐bis(tri‐tert‐butylsilyl)‐2,2‐bis(2,4,6‐trimethylphenyl)silagermene, was synthesized by the reaction of dilithiosilane (tBu3Si)2SiLi2 with dichlorodimesitylgermane. Its structure was determined by spectroscopic data and X‐ray crystallography, which showed the SiGe length to be 2.2769(8) Å. The silagermene underwent isomerization at 100ˆC to form the corresponding symmetrically substituted isomer (E)‐1,2‐bis(tri‐tert‐butylsilyl)‐1,2‐bis(2,4,6‐trimethylphenyl)silagermene. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:649–653, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20503 相似文献