Total Synthesis of Swinholide A: An Exposition in Hydrogen-Mediated C–C Bond Formation
作者:Inji Shin、Suckchang Hong、Michael J. Krische
DOI:10.1021/jacs.6b10645
日期:2016.11.2
Diverse hydrogen-mediated C-C couplings enable construction of the actin-binding marine polyketide swinholide A in only 15 steps (longest linear sequence), roughly half the steps required in two prior total syntheses. The redox-economy, chemo- and stereoselectivity embodied by this new class of C-C couplings are shown to evoke a step-change in efficiency.
多种氢介导的 CC 偶联使肌动蛋白结合海洋聚酮化合物 swinholide A 的构建只需 15 个步骤(最长的线性序列),大约是之前两次全合成所需步骤的一半。这种新型 CC 偶联所体现的氧化还原经济性、化学和立体选择性被证明会引起效率的逐步变化。
Intramolecular Stereoselective Protonation of Aldehyde-Derived Enolates
作者:Anastasie Kena Diba、Claudia Noll、Michael Richter、Marc Timo Gieseler、Markus Kalesse
DOI:10.1002/anie.201004619
日期:2010.11.2
Picking sides: Asymmetric protonation of the titled compounds poses a most significant challenge and has been addressed by taking advantage of internal protonation and subsequent hemiacetal formation to avoid epimerization (see scheme). The substrates employed in these transformations can be easily accessed through a sequence of vinylogous aldol reactions with subsequent conjugate reductions.
[4+2] Cycloadditions of Seven‐Membered‐Ring trans‐Alkenes: Decreasing Reactivity with Increasing Substitution of the Seven‐Membered Ring
作者:John Santucci、Jillian R. Sanzone、K. A. Woerpel
DOI:10.1002/ejoc.201600329
日期:2016.6
in [4+2] cycloadditions depends on the substitution pattern on the seven-membered ring. Unhindered trans-alkenes undergo [4+2] cycloadditions with 1,3-diphenylisobenzofuran faster than the most reactive trans-cyclooctene. Increasing the substitution of the seven-membered ring or increasing the electron density of the trans-alkene decreases reactivity with 1,3-dienes in concerted cycloaddition reactions
see text] Stereoselective total synthesis of scytophycin C, a marine 22-membered macrolide displaying potent activity against a variety of human carcinoma cell lines, has been reported in which the polypropionate structure bearing contiguous asymmetric centers was stereospecifically constructed by using new acyclic stereocontrol. This paper describes stereoselective syntheses of the C(1)-C(18) segment
Leptolyngbyolides, Cytotoxic Macrolides from the Marine Cyanobacterium
<i>Leptolyngbya</i>
sp.: Isolation, Biological Activity, and Catalytic Asymmetric Total Synthesis
asymmetric thioamide-aldol reaction using copper(I) complexed with a chiral bidentate phosphineligand to regulate two key stereochemistries of the molecule at the outset. The present total synthesis demonstrates the utility of this reaction for the construction of complex chemical entities. In addition to the total synthesis, this work reports that leptolyngbyolides depolymerize filamentous actin (F-actin)