Copper-catalyzed Z-selective semihydrogenation of alkynes with hydrosilane: a convenient approach to cis-alkenes
摘要:
A copper catalyst generated in situ from widely available copper salt and imidazolium salt in the presence of t-BuOK showed high efficiency for the semihydrogenation of a wide range of internal and terminal alkynes to their corresponding alkenes without obvious over-reduction. Functional groups, such as hydroxyl, nitro, halides, and amino, etc. were tolerated. The Z/E ratios of the obtained alkenes were generally >99%. Finally, semireduction of bulky alkynes also went smoothly. (C) 2014 Elsevier Ltd. All rights reserved.
The present disclosure provides bioorthogonal compositions for delivering agents in a subject. The disclosure also provides methods of producing the compositions, as well as methods of using the same.
Kumada–Corriu Cross Coupling Route to the Anti-Cancer Agent Combretastatin A-4
作者:Alejandro A. Camacho-Dávila
DOI:10.1080/00397910802238692
日期:2008.10.22
Abstract A short and efficient synthesis of the anticancer agent combretastatin A-4 was accomplished from inexpensive starting materials using the iron-catalyzed cross-coupling of a Grignard reagent and a bromostilbene as the keystep.
protocols for Wittigreaction and palladium-catalyzed Heck coupling give expedient access to a series of unprecedented polyfunctionalized artificial-resveratrol derivatives. In the modified Wittig protocol, trimethylsilyl was used as a highly valuable protective group of the phenolic functions of starting aromatic materials. A clean O-alkylation of hydroxylated stilbenes with ethylene carbonate was
Synthesis and Cytotoxicity Studies of Stilbene Long-Chain Fatty Acid Conjugates
作者:Thomas Wong、Silpa Narayanan、David P. Brown、Zhe-Sheng Chen
DOI:10.1021/acs.jnatprod.0c00027
日期:2020.5.22
linoleic and linolenic acids, respectively, were determined to have exhibited the most active in vitro assays, with compound 23 exhibiting very similar activity to the parent compound against the NCI-H460 cell line. Our studies further delineated the structurally required Z-geometry of the stilbene moiety and that conjugation of the less active E-stilbenes with the most active fattyacid had minimal or no
cis-Stilbenes were synthesized from trans-cinnamic acids, involving ethylenic-bond bromination and a subsequent one-pot microwave-promoted stereoselective debrominative decarboxylation-Suzuki cross-coupling strategy. This sequence represents a useful way to prepare a variety of combretastatin A-4 derivatives.