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111.
Won‐Young Cha Jong Min Lim Dr. Min‐Chul Yoon Young Mo Sung Byung Sun Lee Sho Katsumata Masaaki Suzuki Hirotaka Mori Prof. Dr. Yoshiya Ikawa Prof. Dr. Hiroyuki Furuta Prof. Dr. Atsuhiro Osuka Prof. Dr. Dongho Kim 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(49):15838-15844
meso‐Hexakis(pentafluorophenyl)‐substituted neutral hexaphyrin with a 26π‐electronic circuit can be regarded as a real homolog of porphyrin with an 18π‐electronic circuit with respect to a quite flat molecular structure and strong aromaticity. We have investigated additional aromaticity enhancement of meso‐hexakis(pentafluorophenyl)[26]hexaphyrin(1.1.1.1.1.1) by deprotonation of the inner N? H groups in the macrocyclic molecular cavity to try to induce further structural planarization. Deprotonated mono‐ and dianions of [26]hexaphyrin display sharp B‐like bands, remarkably strong fluorescence, and long‐lived singlet and triplet excited‐states, which indicate enhanced aromaticity. Structural, spectroscopic, and computational studies have revealed that deprotonation induces structural deformations, which lead to a change in the main conjugated π‐electronic circuit and cause enhanced aromaticity. 相似文献
112.
Hiroyuki Shinchi Dr. Masahiro Wakao Sho Nakagawa Eiko Mochizuki Prof. Susumu Kuwabata Prof. Yasuo Suda 《化学:亚洲杂志》2012,7(11):2678-2682
Sugar chains are important molecules in cellular recognition and signaling, and quantum dots (QDs) are a very powerful tool for in vitro and in vivo imaging. Herein, we report the preparation of stable sugar‐chain‐immobilized fluorescent nanoparticles (SFNPs) and their application to the analysis of sugar‐chain–protein interactions and cellular imaging. SFNPs were easily prepared by mixing CdTe/CdS core/shell QDs with our previously developed sugar‐chain–ligand conjugates. The obtained SFNPs were very stable and could be stored for several months. In the binding analysis, β‐galactose‐ and α‐glucose‐immobilized SFNPs were specifically interacted with Ricinus communis agglutinin I and concanavalin A, respectively, and made into aggregates. The binding interaction was detected visually, fluorescently, or both. In the experiment for cellular imaging, it was found that SFNPs were predominantly taken up by human hepatocyto carcinoma cells (HepG2), suggesting the possible usage of our designed SFNPs for various biochemical analyses of sugar chains. 相似文献
113.
Rhodium and iridium complexes bearing a tridentate [PEP] type ligand ([PEP] = {o-(Ph(2)P)C(6)H(4)}(2)E(Me); E = Ge or Sn) were synthesized through the phosphine exchange reaction accompanied by selective E-C bond cleavage. The ligand precursors {o-(Ph(2)P)C(6)H(4)}(2)EMe(2) (E = Ge or Sn) were readily obtained in excellent yields by treating {o-(Ph(2)P)C(6)H(4)}(2)Li with 0.5 equivalents of Me(2)ECl(2). Tris(triphenylphosphine)rhodium(i) carbonyl hydride M(H)(CO)(PPh(3))(3) (M = Rh, Ir) cleaved one of the E-Me bonds of {o-(Ph(2)P)C(6)H(4)}(2)EMe(2) exclusively to afford the trigonal bipyramidal (TBP) complexes, [PEP]M(CO)(PPh(3)). Square-planar rhodium complexes [PEP]Rh(PPh(3)) were also prepared from the reactions of tetrakis(triphenylphosphine)rhodium(i) hydride Rh(H)(PPh(3))(4) with {o-(Ph(2)P)C(6)H(4)}(2)EMe(2). Further, the trans influence of group 14 elements E (E = Si, Ge, Sn) in [PEP]Rh(PPh(3)) is discussed in terms of the (1)J(Rh-P) coupling constants, indicating that E exhibited a stronger trans labilizing effect in the order Sn < Ge < Si. 相似文献
114.
X.R. WU M. Hirsch A. Staudt H.V. Klapdor-Kleingrothaus Cheng-Rui CHING Tso-Hsiu HO 《理论物理通讯》1993,20(4):453-460
The half-lives for 2νββ decay for all the potential Pp-emitters with A≥70 are calculated by the operator expansion method. Compared with the directly measured half-lives of 76Ge, 82Se, 100Mo and 238U the theoretical values are in excellent agreement with experimental ones. 相似文献
115.
A new method-the operator expansion method is used in neutrinoless double beta decay processes. Both the neutrino mass and mixing of right-handed leptonic current are included. It is shown that for nuclear neutrinoless double beta decay in 2n mechanism, there appear some new terms besides the terms given by the conventional treatment based on closure approximation. The ββ with a Majoron emission is also discussed. 相似文献
116.
We discuss the problem of microcausality in a model of quantized field theory. Under the assumptions that the commutator of the "in" fields satisfies the requirement of translational invariance, we show that, in the case of self-conjugate scalar particles or particles with integer spins, one can deduce the law of microcausality. 相似文献
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