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911.
Pengfei Zhang Dr. Chunyang Yu Yucheng Yin Jörn Droste Sina Klabunde Prof. Michael Ryan Hansen Prof. Yiyong Mai 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(69):16497-16503
Development of high-performance photocatalysts for the conversion of amines is of great importance, but has remained a challenging task. Here, a bis-anthracene fused porphyrin ( AFP ) was synthesized in a high yield by a facile synthetic protocol, which involves a Suzuki coupling for the conjugation of two anthracene groups with a porphyrin ring, followed by oxidative cyclodehydrogenation. When serving as a photocatalyst, AFP exhibits an outstanding photocatalytic performance for the visible-light-induced aerobic oxidation of amines to imines at ambient conditions. Density functional theory calculations revealed that the low energy band gap, caused by the large planar and π-extended porphyrin structure of AFP , contributed to its high photocatalytic performance. 相似文献
912.
Mai Tsubamoto Toan Khanh Le Dr. Minghua Li Dr. Taku Watanabe Dr. Chiemi Matsumi Dr. Prakash Parvatkar Prof. Dr. Hiroshi Fujii Prof. Dr. Nobuo Kato Prof. Dr. Jiazhi Sun Prof. Dr. Junko Ohkanda 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(59):13531-13536
Unusual lipid modification of K-Ras makes Ras-directed cancer therapy a challenging task. Aiming to disrupt electrostatic-driven protein–protein interactions (PPIs) of K-Ras with FTase and GGTase I, a series of bivalent dual inhibitors that recognize the active pocket and the common acidic surface of FTase and GGTase I were designed. The structure-activity-relationship study resulted in 8 b , in which a biphenyl-based peptidomimetic FTI-277 was attached to a guanidyl-containing gallate moiety through an alkyl linker. Cell-based evaluation demonstrated that 8 b exhibited substantial inhibition of K-Ras processing without apparent interference with Rap-1A processing. Fluorescent imaging showed that 8 b disrupts localization of K-Ras to the plasma membrane and impairs interaction with c-Raf, whereas only FTI-277 was found to be inactive. These results suggest that targeting the PPI interface of K-Ras may provide an alternative method of inhibiting K-Ras. 相似文献
913.
Quyen Vu Thi Minh Le Thi Hong Huyen Vu Thi Thu Anh Nguyen Mai Hue Nguyen Thi Dao Phi Thi Linh Nguyen Thuy Van Cuong Pham Huong Doan Thi Mai 《Chemistry of Natural Compounds》2022,58(4):704-707
Chemistry of Natural Compounds - Analysis of an antimicrobial extract prepared from the culture broth of the marine-derived actinomycete Nocardiopsis synnemataformans (HT06 strain) led to the... 相似文献
914.
Li Guoqiang Li Jin Cui Qian Mai Wanshan Zhang Ziqiong Zhang Kaikai Nie Renfeng Hu Wei 《Journal of Solid State Electrochemistry》2020,24(10):2427-2439
Journal of Solid State Electrochemistry - For the rational design of heteroatom-doping carbon catalysts toward the oxygen reduction reaction (ORR), various structure-wise and porous... 相似文献
915.
Mechanism and kinetics of the thermal pyrolysis of ethyl 2-furoate were studied in a wide range of conditions (ie, 500-1500 K and 1-7600 Torr) using the accurate dual-level theory CCSD(T)&MP2(FC)//B3LYP/aug-cc-pVTZ and state-of-the-art Rice-Ramsperger-Kassel-Marcus based master equation rate model including hindered internal rotation and tunneling treatments. The predicted rate coefficients are found to be in accordance with the experimental data. The mechanism details are revealed as (i) the major decomposition channel occurs via a six-center transition state with the barrier energy of 48.3 kcal/mol at 0 K, leading to the formation of C2H4 and 2-furoic acid and (ii) pressure has a slightly positive effect on the rate constant, particularly at the high temperature. Also, the reactivity of ethyl 2-furoate toward OH radicals was discussed in the first place. 相似文献
916.
It has long been known in universal algebra that any distributive sublattice of congruences of an algebra which consists entirely of commuting congruences yields a sheaf representation of the algebra. In this paper we provide a generalization of this fact and prove a converse of the generalization. To be precise, we exhibit a one-to-one correspondence (up to isomorphism) between soft sheaf representations of universal algebras over stably compact spaces and frame homomorphisms from the dual frames of such spaces into subframes of pairwise commuting congruences of the congruence lattices of the universal algebras. For distributive-lattice-ordered algebras this allows us to dualize such sheaf representations. 相似文献
917.
Hieu Thanh Nguyen Tam Van-Thanh Mai Lam Kim Huynh 《Journal of computational chemistry》2019,40(13):1360-1373
Based on our modified classification of elemental species, a framework for automatic generation of multilevel Homodesmotic fragment-separation (mHDFS) reactions for chemical species was proposed. Combined the mHDFS framework with a database of heat of formation (HoF) and the calculated electronic structure data for the elemental mHD species, the mHDFS-HoF program was constructed in C/C++ language to calculate heat of formation for a species of interest on-the-fly. Using the electronic structure data calculated at CBS-QB3 level of theory for the elemental mHD species, applications and robustness of the code were discussed with several acyclic hydrocarbon systems including neutral and radical species. On-going work and extension to other systems were also discussed. The program and the supporting files can be freely downloaded at https://sites.google.com/view/mhdfs/ . © 2019 Wiley Periodicals, Inc. 相似文献
918.
919.
反应图是一种呈现有机物间相互转化关系的网络示意图,学生制作反应图的过程称作反应构图。在界定反应图和说明其特点、分类和制作步骤的基础上,提出开展反应构图教学活动的设计理念和实践思路。通过教学实践和态度问卷调查,了解该教学活动的实际成效,并对活动期间出现的问题进行了讨论。 相似文献
920.
Yuhai Wang Hao Shen Gu Li Kancheng Mai 《Journal of Thermal Analysis and Calorimetry》2010,99(2):399-407
The effect of different interfacial interaction on the crystallization and melting behavior of PP/nano-CaCO3 composites was investigated using differential scanning calorimetry, X-ray diffraction and polarized optical microscope.
The results indicated that nano-CaCO3 acted as heterogeneous nuclei for PP crystallization. There existed a synergistic effect of heterogeneous nucleation between
nano-CaCO3 and compatibilizer for PP crystallization, which was proved by increasing the crystallization rate and decreasing the fold
surface free energy as well as favoring the formation of β-crystal of PP. However, this synergistic effect was dependent on
the interfacial interaction between PP and compatibilizer. The increased miscibility between compatibilizer and PP favored
this synergistic effect. 相似文献