Baker's yeast mediated biohydrogenation of sulphur-functionalised methacrolein derivatives. Stereochemical aspects of the reaction and preparation of the two enantiomers of useful C4 bifunctional chiral synthons
作者:Stefano Serra、Claudio Fuganti
DOI:10.1016/s0957-4166(01)00383-4
日期:2001.8
baker's yeast mediated reduction of sulphur-functionalised methacroleins 11, 15 and 18 leads to the preparation of the bifunctional methyl branched C4 chiral synthons 6 and 7. The stereochemicalaspects of the biohydrogenation have been investigated. Both the oxidation state of sulphur and the isomeric position of the double bond affected the enantioselectivity of the reduction strongly, thus, offering
Conjugated Dienyne‐Imides as Robust Precursors of 1‐Azatrienes for 6π Electrocyclizations to Furo[2,3‐
<i>b</i>
]dihydropyridine Cores
作者:Yanjun Wan、Xuchun Zheng、Cheng Ma
DOI:10.1002/anie.201800303
日期:2018.5.4
intermediates for 6πelectrocyclizations was developed by using readily accessible dienyne‐imides and various terminal olefins under PdII catalysis. Taking advantage of the sequential cooperation between preloaded and incorporated functional handles at 1,3‐dien‐5‐yne skeletons, this method not only enables the selective generation of putative 1‐azatrienes but significantly accelerates their thermal 6π‐electrocyclic
通过在Pd II催化下使用易得的二烯炔-酰亚胺和各种末端烯烃,开发了一种新的策略来生成用于6π电环化的功能化1-氮杂三烯中间体。利用这种方法,可以在1,3-dien-5-yne骨架上预先加载和合并功能手柄之间的顺序配合,不仅可以选择性地生成假定的1-氮杂氮杂环丁烷,而且还可以显着加速其6π-电热环闭环反应的过程。一系列高产率的呋喃[2,3- b ]二氢吡啶衍生物。
Enantioselective Total Syntheses and Absolute Configuration of JBIR-02 and Mer-A2026B
作者:Johannes Hoecker、Karl Gademann
DOI:10.1021/ol303502a
日期:2013.2.1
The first total syntheses of the piericidin related natural products Mer-A2026B and JBIR-02 are reported. Key features of the synthetic approach involve an Ir-catalyzed one-pot C–H activation/oxidation procedure for the preparation of the hydroxypyridine, a vinylogous Mukaiyama aldol reaction, and a final Negishi cross-coupling of an advanced pyridine derivative with an allylic side chain precursor
作者:Heemal H. Dhanjee、Matthew W. Haley、Travis C. McMahon、Jonas F. Buergler、Jennifer M. Howell、Yutaka Kobayashi、Koichi Fujiwara、John L. Wood
DOI:10.1016/j.tet.2016.03.011
日期:2016.6
Efforts to install the core azepine ring in tetrapetalone A via a palladium π-allyl cascade reaction failed due to competing pathways that included an unexpected and interesting TMM-like cycloaddition reaction that delivers a complex tricyclic ring system.
efficient and flexible synthesis has hindered further biological studies, mostly due to the fact that the natural products appear to be kinetic isomers regarding the triene moiety. Herein, we report the development and application of an unprecedented, unique domino Suzuki–Miyaura/4π-electrocyclic ring-opening macrocyclization, resulting in a concise, unified, and stereoselective synthetic route to these complex
FR252921、FR252922 和 FR256523 是一类具有新作用方式的强效大环多烯免疫抑制剂。然而,缺乏有效和灵活的合成阻碍了进一步的生物学研究,主要是由于天然产物似乎是关于三烯部分的动力学异构体。在此,我们报告了一种前所未有的、独特的多米诺 Suzuki-Miyaura/4π-电环开环大环化的开发和应用,只需 10 个步骤即可获得这些复杂目标的简明、统一和立体选择性合成路线。这反过来又使人们能够很容易地获得一系列非天然类似物,其中几种化合物对 T 淋巴细胞增殖的抑制水平与天然产物本身相同或更高。