Biomimetic Total Synthesis of Angelicoin A and B via a Palladium-Catalyzed Decarboxylative Prenylation-Aromatization Sequence
摘要:
Five-step total syntheses of angelicoin A and B from 2,2,6-trimethyl-4-dioxinone are reported using late stage biomimetic aromatization reactions via diketo-dioxinones as intermediates. In addition, with angelicoin A, this aromatization was coupled with a palladium-catalyzed decarboxylative prenylation in a one-pot sequence as the key step.
Gregatins AD 和 Aspertetronin A 的全合成:这些化合物和 Aspertetronin B 的结构修正,以及 Gregatin E、环凝集素、Graminin A、Penicilliols A 和 B 以及 Huaspenones A 的合理结构修正
摘要:
呋喃酮核 a、b 和 c 中 1H 和 13C NMR 化学位移值的综合比较为从 b 到 c 重新评估标题化合物的呋喃酮核提供了合理的支持。通过对映异构纯乳酸酯的总合成基于 Seebach-Frater“立体中心的自我复制”方法。通过将 Seebach-Frater 烯醇化物添加到 trans-hex-4-en-1-al 而不是 trans-hex-3-en-1- 来实现以反式、反式选择性方式连接己二烯基侧链阿尔。合成材料的 c 型呋喃酮核心是通过模型 γ-羟基-β-氧代酯(化合物 50)及其含己二烯的对应物 29 的单酰化或双酰化实现的。我们的合成证实了六种化合物的新型连接性。此外,在五种情况下,他们需要修改季碳原子的构型。此外,他们允许阐明四个以前未分配的立体中心的配置。给出了为什么标题化合物的呋喃酮核心被误解为 a 和/或 b 而不是 c 的事后分析。还讨论了为什么杂环中的立体中心配置不正确,基于
Biomimetic Synthesis of Resorcylate Natural Products Utilizing Late Stage Aromatization: Concise Total Syntheses of the Marine Antifungal Agents 15G256ι and 15G256β
作者:Ismael Navarro、Jean-François Basset、Séverine Hebbe、Sarah M. Major、Thomas Werner、Catherine Howsham、Jan Bräckow、Anthony G. M. Barrett
DOI:10.1021/ja803445u
日期:2008.8.1
sequential reaction with potassium carbonate and methanolic hydrogen chloride to give resorcylate esters. The reaction was applied in the total synthesis of the marine antifungal agents 15G256beta (1), 15G256iota (2), and 15G256pi (3) and the mycotoxin S-(-)-zearalenone (4).
2-Cyano-3,5-dihydroxyhex-2-enecarboxamide derivatives ##STR1## are suitable for the production of pharmaceuticals for the prophylaxis and therapy of diseases or dissorders whose course involves increased connective tissue or cartilage degradation.
2-Cyano-3,5-dihydroxyhex-2-enecarboxamide derivatives
are suitable for the production of pharmaceuticals for the prophylaxis and therapy of diseases or disorders whose course involves increased connective tissue or cartilage degradation.
Mechanism of an acid chloride-imine reaction by low-temperature FT-IR: .beta.-lactam formation occurs exclusively through a ketene intermediate
作者:Joseph E. Lynch、Stephen M. Riseman、William L. Laswell、Ralph P. Volante、George B. Smith、Ichiro Shinkai、David M. Tschaen
DOI:10.1021/jo00277a011
日期:1989.8
Total Syntheses of Angelicoin A, Hericenone J, and Hericenol A via Migratory Prenyl- and Geranylation–Aromatization Sequences
作者:Jens Cordes、Frederick Calo、Katie Anderson、Toni Pfaffeneder、Sylvain Laclef、Andrew J. P. White、Anthony G. M. Barrett
DOI:10.1021/jo202354j
日期:2012.1.6
A five-step synthesis of the natural product angelicoin A using a late stage highly regioselective palladium(0)-catalyzed decarboxylative prenyl migration and aromatization sequence as the key step is reported. The method was extended with geranyl migration in eight-step total syntheses of hericenone J and hericenol A from geraniol.