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981.
Marina Yamamoto Raynbird Dr. Filipa Silva Harry Smallman Dr. Shaista S. Khokhar Dr. Daniel Neef Dr. Gareth J. S. Evans Prof. Dr. Thomas Wirth 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(38):8363-8367
A short total synthesis of ajoene, (E,Z)-4,5,9-trithiadodeca-1,6,11-triene 9-oxide, has been achieved over six steps. In addition, a continuous flow synthesis under mild reaction conditions to (E,Z)-4,5,9-trithiadodeca-1,7,11-triene is described starting from simple and easily accessible starting materials. Over four steps including propargylation, radical addition of thioacetate, deprotection, and disulfide formation/ allylation, the target product can be obtained at a rate of 0.26 g h−1 in an overall yield of 12 %. 相似文献
982.
Atsushi Sudo Kyohei Nishiyama Mika Morimoto Shinichiro Yamamoto 《Journal of polymer science. Part A, Polymer chemistry》2020,58(14):1973-1981
Dimethacrylates with rigid adamantane-like cores were synthesized from myo-inositol orthoester via a sequence of (a) acylation or silylation of the equatorially oriented hydroxyl group, followed by (b) attachment of methacrylate groups on the axially oriented hydroxyl groups. The radical homopolymerization of these compounds proceeded via cyclopolymerization without crosslinking, as the two axially oriented methacrylate groups were fixed in close proximity with each other. The dimethacrylates underwent radical copolymerization with methyl methacrylate (MMA) to afford the corresponding polymethacrylates, exhibiting high glass transition temperatures (Tg), due to the introduction of the rigid orthoester moieties originating from the monomers and the macrocyclic structures formed via intramolecular cyclization of the two methacrylate groups of the monomers. The polymers obtained by polymerization of the dimethacrylate bearing a silylated hydroxyl group served as precursors of hydroxyl-bearing polymers, which also exhibited high Tg due to the formation of a hydrogen bonding network between the hydroxyl groups. 相似文献
983.
We consider the heat equation with a superlinear absorption term in and study the existence of nonnegative solutions with an m-dimensional time-dependent singular set, where . We prove that if , then there are two types of singular solutions. Moreover, we show the uniqueness of the solutions and specify the exact behavior of the solutions near the singular set. 相似文献
984.
The magnetic properties of intermetallic compounds RMn6Sn6 (T=Gd and Y) have been investigated by119Sn Mössbauer effect measurements. The differences of the hyperfine field on both the Sn1 and Sn3 sites were small between GdMn6Sn6 and YMn6Sn6, while the Mn sublattice orders ferromagnetically for R=Gd and antiferromagnetically for R=Y. This result indicated that Mn moments order antiferromagnetically in the intra-plane of the Kagomè net in YMn6Sn6. 相似文献
985.
986.
Junji Nakano Moon Yul Huh Yoshikazu Yamamoto Takeshi Fujiwara Ikunori Kobayashi 《Computational Statistics》2004,19(1):137-146
Summary Jasp is an experimental general purpose Java-based statistical system which adopts several new computing technologies. It
has a function-based and object-oriented language, an advanced user interface, flexible extensibility and a server/client
architecture with distributed computing abilities. DAVIS is, on the other hand, a stand-alone Java-based system, and is designed
for providing advanced data visualization functions with easy operations by a GUI. In this paper, it is made possible to use
tools of DAVIS from within Jasp, in order that the new integrated system can handle not only data filtering and statistical
analysis but also data visualization. We develop a mechanism for extending the server/client system of Jasp to realize an
efficient collaboration with DAVIS in the client-side. It is shown that the mechanism is straightforward and simple. 相似文献
987.
S Sumiya T Yoneda K Kitamura M Murata C Yokoo M Tamai A Yamamoto M Inoue T Ishida 《Chemical & pharmaceutical bulletin》1992,40(2):299-303
To design a potent inhibitor specific for cathepsin B (rat liver), the tertiary structure was predicted based on the crystal structure of the papain complexed with (+)-(2S,3S)-3-(1-[N-(3-methylbutyl)amino]leucylcarbonyl)oxirane-2- carbolylic acid (E-64-c), a thiol protease inhibitor. Taking advantage of the structural characteristics of the predicted active site, seventeen inhibitors were chemically synthesized by molecular modeling, and one of them, N-(L-3-trans-propylcarbamoyloxirane-2-carbonyl)-L-isoleucyl-L-p rol ine (CA-074) was shown to be the first potent inhibitor specific for cathepsin B. The relationship between the structure and inhibitory activity is discussed based on the model structure of the cathepsin B-inhibitor complex. 相似文献
988.
Katsuhiko Tahara Eiji Nagahara Yasushi Itoi Satoru Nishiyama Shigeru Tsuruya Mitsuo Masai 《Reaction Kinetics and Catalysis Letters》1996,59(1):15-18
The conversion of a carboxylic acid was increased to 90% with 100% selectivity to the corresponding alcohol by calcination of the catalyst precursor, Sn/alumina, of Ru–Sn/alumina in the hydrogenation of the carboxylic acid. 相似文献
989.
Akihiko Kitada Yoshihito Ogasawara Tomoyuki Yamamoto 《Chaos, solitons, and fractals》2007,34(5):1732-1735
Let S be a zero-dimensional, perfect, compact weak self-similar set generated in dendrite X by a family {fj} of weak contractions from X to itself. Decomposition space Df of S due to a continuous mapping f from S onto X is also a dendrite. In the dendrite Df, there exists a zero-dimensional, perfect, compact weak self-similar set S1 based on a family each of which is topologically conjugate to fj. Decomposition space Df1 of S1 due to a continuous mapping f1 from S1 onto Df is again a dendrite. In this manner, through the successive formation of weak self-similar set, we can obtain a sequence X,Df,Df1,… of dendrite any pair in which are mutually homeomorphic. 相似文献
990.