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Alexander JP Bebek C Berger BE Berkelman K Bloom K Browder TE Cassel DG Cho HA Coffman DM Crowcroft DS Dickson M Drell PS Dumas DJ Ehrlich R Elia R Gaidarev P Garcia-Sciveres M Gittelman B Gray SW Hartill DL Heltsley BK Henderson S Jones CD Jones SL Kandaswamy J Katayama N Kim PC Kreinick DL Lee T Liu Y Ludwig GS Masui J Mevissen J Mistry NB Ng CR Nordberg E Patterson JR Peterson D Riley D Soffer A Avery P Freyberger A Lingel K Prescott C Rodriguez J Yang S Yelton J Brandenburg G Cinabro D 《Physical review D: Particles and fields》1996,53(3):R1013-R1017
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Kazuharu Ienaga Atsushi Yamamoto Toshio Yamada Yoshinori Joh 《Journal of heterocyclic chemistry》1988,25(3):1037-1038
A novel derivative of urocanic acid ( 1 ) had been isolated from acetone extracts of rabbit skin tissue. It proved to be (E)-3-[1-(1,1-dimethyl-3-oxobutyl)imidazol-4-yl]propenoic acid ( 3c ), potentially a much better ultraviolet screening agent than urocanic acid. Sterical effect of dimethyl groups in the side chain adjacent to the imidazole ring of 3c on its solubility is also discussed. 相似文献
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Yoshihiko Yamamoto Prof. Dr. Ken Yamashita Tomitaka Hotta Toru Hashimoto Makoto Kikuchi Dr. Hisao Nishiyama Prof. Dr. 《化学:亚洲杂志》2007,2(11):1388-1399
Spirocyclic C‐arylglycosides were synthesized from the appropriately protected δ‐gluconolactones. Addition of lithium acetylide followed by glycosylation with 3‐(trimethylsilyl)propargyl alcohol converted the δ‐gluconolactones into silylated diynes. After desilylation, subsequent ruthenium‐catalyzed cycloaddition of the resultant diynes with alkynes or chloroacetonitrile gave spirocyclic C‐arylglycosides in good yields and selectivity. This strategy was also extended to the synthesis of spirocyclic C‐arylribosides from the known γ‐ribonolactone derivative. Moreover, silver‐catalyzed iodination of the sugar diynes followed by ruthenium‐catalyzed cycloaddition with acetylene delivered spirocyclic C‐iodophenylglycosides and ‐ribosides, which were subjected to palladium‐catalyzed C? C bond‐forming reactions and copper‐catalyzed coupling with nitrogen heterocycles to lead to various derivatives. 相似文献
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Uchiyama S Ohshima A Nakamura S Hasegawa J Terui N Takayama SJ Yamamoto Y Sambongi Y Kobayashi Y 《Journal of the American Chemical Society》2004,126(45):14684-14685
The complete thermal-unfolding profiles of both oxidized and reduced forms of cytochrome c551 (PA) from mesophilic Pseudomonas aeruginosa and cytochrome c552 (HT) from thermophilic Hydrogenobacter thermophilus were obtained by the newly developed pressure-proof cell compartment installed in a circular dichroic spectrometer, which facilitates protein thermal-unfolding experiments up to 180 degrees C. The thermodynamic cycle, which relates protein stability and redox function, indicated that the redox potentials of PA and HT in the native state are regulated by the stability of the oxidized proteins rather than by that of the reduced ones. 相似文献