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991.
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K Iwasaki R Kanno T Morimoto T Yamashita S Yokoshima T Fukuyama 《Angewandte Chemie (International ed. in English)》2012,51(36):9160-9163
What a core-ker! The title synthesis was achieved using a route featuring an intramolecular Mitsunobu reaction of a nosyl amide, stereoselective construction of the β-lactam, and formation of an enamide moiety by selenoxide elimination. The stereochemistry of the alkylation for the formation of the β-lactam was controlled by a secondary hydroxy group on the ten-membered ring. SEM=2-(trimethylsilyl)ethoxymethyl; TBS=tert-butyldimethylsilyl. 相似文献
993.
Quideau S Deffieux D Pouységu L 《Angewandte Chemie (International ed. in English)》2012,51(28):6824-6826
A votre Santé! The mechanism by which resveratrol, a hydroxystilbenoid polyphenol found in grapes and present in wine, exerts antiaging metabolic benefits has been uncovered. Chung and co-workers have found that it works by inhibiting cAMP phosphodiesterases, thus triggering a signaling cascade that leads to the possible activation of the mammalian enzyme sirtuin?1. 相似文献
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Allenes are the simplest class of cumulenes, with two contiguous C=C bonds, and show unique physical and chemical properties. These features make allenes particularly attractive in modern organic chemistry. In this Review, attention is paid to the advances made in catalytic asymmetric synthesis and natural product syntheses based on well-established reactions of allenes, such as propargylation, addition, cycloaddition, cycloisomerization, cyclization, etc., with or without catalysts. Their versatile reactivity, substituent-loading ability, axial to center chirality transfer, and controllable selectivity allow access to target molecules by unique and efficient approaches. The main topics in this Review are presented with selected examples from 2003 to 2011. 相似文献
996.
Takahashi M Kawamura A Kato N Nishi T Hamachi I Ohkanda J 《Angewandte Chemie (International ed. in English)》2012,51(2):509-512
Fluorescent combination: Cell-penetrating probes derived from the diterpene fusicoccin can form ternary complexes with 14-3-3 proteins and phosphopeptide ligands, whereupon the probes site-specifically attach a fluorescent tag onto the surface of the 14-3-3 proteins. 相似文献
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Finefield JM Sherman DH Kreitman M Williams RM 《Angewandte Chemie (International ed. in English)》2012,51(20):4802-4836
In nature, chiral natural products are usually produced in optically pure form-however, occasionally both enantiomers are formed. These enantiomeric natural products can arise from a single species or from different genera and/or species. Extensive research has been carried out over the years in an attempt to understand the biogenesis of naturally occurring enantiomers; however, many fascinating puzzles and stereochemical anomalies still remain. 相似文献