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51.
Koyuki Sakai Hiroki Nishiyama Shinsuke Inagi Ikuyoshi Tomita Yusuke Hibi Motonori Komura Keiji Nose Tomokazu Iyoda 《Journal of polymer science. Part A, Polymer chemistry》2019,57(24):E1-E8
A block copolymer composed of a flexible polar poly(ethylene glycol) (PEG) and a less polar liquid crystalline poly(allene) segments is prepared by the living coordination polymerization of an allene derivative possessing trans‐azobenzene‐containing mesogenic substituent by the use of a π‐allylnickel macroinitiator bearing PEG segment. The thin film of the block copolymer is prepared by the spin coating of its solution onto mica or silicon wafer which proves to possess perpendicularly oriented nanocylindrical microphase separated structures as supported by the differential calorimetric, polarized optical microscopic, grazing‐incidence small‐angle X‐ray scattering, transmission electron microscope, and atomic force microscope measurements. 相似文献
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Enhancement of Light Absorption Ability of Synthetic Chlorophyll Derivatives by Conjugation with a Difluoroboron Diketonate Group
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Dr. Yusuke Kinoshita Dr. Yuichi Kitagawa Prof. Dr. Hitoshi Tamiaki 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(29):9996-10001
The enhancement of the light absorption ability of synthetic chlorophyll derivatives is demonstrated. Chlorophyll derivatives directly conjugated with a difluoroboron 1,3‐diketonate group at the C3 position were synthesized from methyl pyropheophorbide‐d through Barbier acylmethylation of the C3‐formyl moiety, oxidation of the C3‐carbinol, and difluoroboron complexation of the diketonate. Electronic absorption spectra in a diluted solution showed that the synthetic conjugates gave an absorption band at λ=400–500 nm, with a Qy band shifted to a longer wavelength of λ≈700 nm. DFT calculations demonstrated that the absorption bands and redshifts were ascribable to the coupling of the LUMO of chlorin with that of the difluoroboron diketonate moiety. The introduction of a pyrenyl group at the C33‐position of the conjugate afforded an additional charge‐transfer band over λ=500 nm, producing a pigment that bridged the green gap in standard chlorophylls. 相似文献
53.
Hiroyuki Abe Hajime Otsuka Yutaka Sakamura Yusuke Yamada 《The European Physical Journal C - Particles and Fields》2012,72(5):1-22
We perform a comprehensive and systematic analysis of the SUSY flavor structure of generic 5D supergravity models on S 1/Z 2 with multiple Z 2-odd vector multiplets that generate multiple moduli. The SUSY flavor problem can be avoided due to contact terms in the 4D effective K?hler potential peculiar to the multi-moduli case. A?detailed phenomenological analysis is provided based on an illustrative model. 相似文献
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Total Synthesis of the 7,10‐Epimer of the Proposed Structure of Amphidinolide N,Part II: Synthesis of C17–C29 Subunit and Completion of the Synthesis
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Dr. Koji Ochiai Dr. Sankar Kuppusamy Yusuke Yasui Kenji Harada Dr. Nishant R. Gupta Dr. Yohei Takahashi Prof. Dr. Takaaki Kubota Prof. Dr. Jun'ichi Kobayashi Prof. Dr. Yujiro Hayashi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(10):3287-3291
The total synthesis of 7,10‐epimer of the proposed structure of amphidinolide N was accomplished. The requisite chiral C17–C29 subunit was assembled stereoselectively via Keck allylation, Shi epoxidation, diastereoselective 1,3‐reduction, and a later oxidative synthesis of the THF framework. The C1–C13 and C17–C29 subunits were successfully coupled using a Enders RAMP “linchpin” as the C14–C16 three carbon unit, thereby controlling the chirality at C14 and C16. The labile allyl epoxy moiety was successfully constructed by Grieco–Nishizawa olefination at a final stage of the synthesis. 相似文献
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Silacyclophanes possessing two disilanyl pillars were synthesized from tricyclic heteroarenes in one‐pot synthetic procedures. The step‐like anti structures of three congeners bearing two heteroarene units were revealed in single crystals by X‐ray crystallographic analysis. Depending on the structures of aromatic units, torsion angles at the disilanyl pillars altered to maintain the overall step‐like molecular structures. The structure, however, fluctuated between anti and syn conformers in a solution phase despite the presence of eight methyl groups on the ring periphery. The analysis of the coalescence temperature with NMR spectroscopy showed the fundamental energetics of the dynamics. The subtle structural differences affected the dynamic behavior of the silacyclophanes. 相似文献