作者:Barry M. Trost、Craig E. Stivala、Kami L. Hull、Audris Huang、Daniel R. Fandrick
DOI:10.1021/ja411270d
日期:2014.1.8
Lasonolide A is a novel polyketide displaying potent anticancer activity across a broad range of cancer cell lines. Here, an enantioselective convergent totalsynthesis of the (-)-lasonolide A in 16 longest linear and 34 total steps is described. This approach significantly reduces the step count compared to other known syntheses. The synthetic strategy utilizes alkyne-bearing substrates as core building
Lasonolide A 是一种新型聚酮化合物,在多种癌细胞系中显示出有效的抗癌活性。在此,描述了 (-)-lasonolid A 的对映选择性收敛全合成,包括 16 个最长线性步骤和 34 个总步骤。与其他已知的合成相比,这种方法显着减少了步骤数。该合成策略利用带有炔烃的底物作为核心构建模块,并通过关键的钌催化的烯烃-炔烃偶联和大分子乳酸化将两个相似的复杂半部分缝合在一起。
Total Synthesis of (−)-Lasonolide A
作者:Barry M. Trost、Craig E. Stivala、Daniel R. Fandrick、Kami L. Hull、Audris Huang、Caroline Poock、Rainer Kalkofen
DOI:10.1021/jacs.6b05127
日期:2016.9.14
utilizing a Ru-catalyzed alkene-alkyne coupling. This type of coupling typically generates branched products; however, through a detailed investigation, we are now able to demonstrate that subtle structural changes to the substrates can alter the selectivity to favor the formation of the linear product. The synthesis of the fragments features a number of atom-economical transformations which are highlighted
拉索内酯是新型聚酮化合物,在体外针对多种癌细胞系表现出显着的生物活性。在此,我们描述了正式合成拉索内酯 A 的第一代方法。这些研究的关键发现最终使我们能够继续完成拉索内酯 A 的全合成。收敛方法利用 Ru 催化将两个高度复杂的片段结合在一起。烯烃-炔烃偶联。这种类型的偶联通常会产生支化产物;然而,通过详细的研究,我们现在能够证明底物的细微结构变化可以改变选择性以有利于线性产物的形成。这些片段的合成具有许多原子经济转化的特点,其中突出的是发现了一种工程酶,可以对 β-酮酯进行动态动力学还原,从而建立具有高水平对映选择性的南四氢吡喃环的绝对立体化学。
The formation of allyl sulphides by phenylthio-migration: control by silicon
作者:Ian Fleming、Ian Paterson、Andrew Pearce
DOI:10.1039/p19810000256
日期:——
a tertiary migration terminus (4)→(6). Geraniol/nerol (12) and linalool (14) have been synthesised from a common intermediate (11) using this type of reaction. Phenylthio-migration from a tertiary migration origin (17)→(3) can be controlled to a limited extent by a suitably placed silyl group, but it is easier to achieve direct β-elimination of the silyl and phenylthio-groups (17)→(18).
Stereoselective Total Synthesis of the Natural (+)-Lasonolide A
作者:Sung Ho Kang、Suk Youn Kang、Hyeong-wook Choi、Chul Min Kim、Hyuk-Sang Jun、Joo-Hack Youn
DOI:10.1055/s-2004-822340
日期:——
The natural (+)-lasonolide A (1), an anti-tumor agent, has been synthesized via thermodynamic benzylidene formation at the C 2 2 quaternary chiral center, use of a disulfone equivalent for elongation of the C 1 5 -C 1 7 three-carbon chain as well as introduction of the two trans olefins at C 1 5 and C 1 7 , iodocyclization for the upper THP. Michael addition for the bottom THP, and intramolecular Horner-Emmons
天然 (+)-lasonolide A (1) 是一种抗肿瘤剂,通过在 C 2 2 四元手性中心形成热力学亚苄基,使用二砜当量延长 C 1 5 -C 1 7 合成三碳链以及在C 1 5 和C 1 7 处引入两个反式烯烃,上层THP的碘环化。底部 THP 的 Michael 加成和 20 元大环内酯的分子内 Horner-Emmons 烯化。
Enantioselective Rhodium‐Catalyzed Pauson‐Khand Reactions of 1,6‐Chloroenynes with 1,1‐Disubstituted Olefins
作者:Ridge Michael P. Ylagan、Eric Jaewon Lee、Daniela E. Negru、Paolo Ricci、Bohyun Park、Haram Ryu、Mu-Hyun Baik、P. Andrew Evans
DOI:10.1002/anie.202300211
日期:——
An enantioselective RhI-catalyzed Pauson–Khand reaction (PKR) using 1,6-chloroenynes with challenging 1,1-disubstituted olefins is described. DFT calculations reveal that the halide pre-polarizes the alkyne to lower the barrier for the metallacycle formation and provides the proper steric profile to permit a favorable enantiodetermining interaction between the 1,6-chloroenyne and the chiral diphosphine