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271.
272.
Synthesis and antifungal activity of novel 14-membered benzomacrolides, as galbonolide analogues 总被引:1,自引:0,他引:1
Sakoh H Sakuraba S Sugimoto Y Imamura H Jona H Yamada K Bamba-Nagano R Hashizume T Morishima H 《Chemical & pharmaceutical bulletin》2004,52(1):163-165
Asymmetric total synthesis of benzene analogues of galbonolide, a 14-membered antifungal macrolide, possessing a benzene ring instead of a conjugated diene structure, was achieved starting from chiral 1-aryl-1-propanol obtained by enzyme-catalyzed kinetic resolution with high enantioselectivity. Representatively, a method for the introduction of a methylthio and chloride function at the vinyl position was also established. The resulting analogues unfortunately exhibited very little antifungal potency in comparison with galbonolide A. 相似文献
273.
Matsushita S Yanai Y Fusyuku A Ikeda T Ono M Nohara T 《Chemical & pharmaceutical bulletin》2007,55(7):1079-1081
It has been revealed that the absolute configurations at C-22 of 23-hydroxyspirostane and 23-hydroxyspirosolane could be unambiguouly judged by the (1)H- and (13)C-NMR spectroscopies. 相似文献
274.
Mitsunori Oda Kazutaka Ogura Sayaka Kishi Kunihide Fujimori Noritaka Abe 《Tetrahedron letters》2007,48(26):4471-4475
The title azaazulene 3 was synthesized either by reaction of tropone with N-{(2-pyridyl)acetyl}pyridinium iodide in the presence of ammonium acetate or by palladium-catalyzed cross-coupling between 2-halo-1-azaazulene and 2-substituted pyridine. The compound shows relatively stronger basicity compared with 2,2′-bipyridyl. While 3 showed no emission from the S1 state but from the S2 state like azulene does, the protonated species of 3 exhibited emission from the S1 state. Cationic metal-dependent absorption and emission relating to complexation were also studied. 相似文献
275.
Shibata S Zhang Z Korotkov KV Delarosa J Napuli A Kelley AM Mueller N Ross J Zucker FH Buckner FS Merritt EA Verlinde CL Van Voorhis WC Hol WG Fan E 《Analytical and bioanalytical chemistry》2011,401(5):1585-1591
Ultrafiltration provides a generic method to discover ligands for protein drug targets with millimolar to micromolar K(d), the typical range of fragment-based drug discovery. This method was tailored to a 96-well format, and cocktails of fragment-sized molecules, with molecular masses between 150 and 300 Da, were screened against medical structural genomics target proteins. The validity of the method was confirmed through competitive binding assays in the presence of ligands known to bind the target proteins. 相似文献
276.
277.
Akine S Hotate S Matsumoto T Nabeshima T 《Chemical communications (Cambridge, England)》2011,47(10):2925-2927
The left-handed isomer of the helical complex [LZn(3)La(OAc)(3)] was spontaneously enriched from 50 : 50 to 87 : 13 when the quasiracemate crystals were dissolved. The invertible helicity of [LZn(3)La(OAc)(3)] (global chirality) helps the quasiracemate formation and the fixed point chirality of the R,R-cyclohexanediamine moiety (local chirality) effectively controls the global chirality in solution. 相似文献
278.
Dr. Tomohiro Seki Sayaka Kurenuma Prof. Dr. Hajime Ito 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(48):16214-16220
We report the luminescent color tuning of a new complex, 2‐benzothiophenyl(4‐methoxyphenyl isocyanide)gold(I) ( 1 ), by using a new “polymorph doping” approach. The slow crystallization of the complex 1 afforded three different pure polymorphic crystals with blue, green, and orange emission under UV‐light irradiation. The crystal structures of pure polymorphs of 1 were investigated in detail by means of single‐crystal X‐ray analyses. Theoretical calculations based on the single‐crystal structures provided qualitative explanation of the difference in the excited energy‐levels of the three polymorphs of 1 . In sharp contrast, the rapid precipitation of 1 , with the optimized conditions reproducibly afforded homogeneous powder materials showing solid‐state white‐emission with Commission Internationale de l’Éclairage (CIE) 1931 chromaticity coordinates of (0.33, 0.35), which is similar to pure white. New “polymorphic doping” has been revealed to be critical to this white emission through spectroscopic and X‐ray diffraction analyses. The coexistence of the multiple polymorphs of 1 within the homogeneous powder materials and the ideal mixing of multiple luminescent colors gave its white emission accompanied with energy transfer from the predominant green‐emitting polymorph to the minor orange‐emitting polymorph. 相似文献
279.