报道了 malbrancheamide 和 malbrancheamide B 的仿生全合成。两种一氯物质的合成使得 Malbrancheamide B 的结构能够被明确指定。这些合成均以 5-羟基吡嗪-2(1 H )-one 的分子内 Diels-Alder 反应为特征,以构建双环[2.2.2]二氮杂辛烷核心,这也被提议作为这些化合物的生物合成途径。
Herein we describe compositions and methods for the synthesis of [2.2.2]-diazabicyclic structures comprising a domino reaction sequence involving aldol condensation, alkene isomerization, and intramolecular hetero-Diels-Alder cycloaddition. Excellent diastereofacial control during the cycloaddition is enforced with a removable chiral phenyl aminal diketopiperazine substituent. The reaction sequence rapidly generates molecular complexity and is competent with both enolizable and non-enolizable aldehyde substrates. This method provides an efficient route to [2.2.2]-diazabicyclic structures, common to bioactive prenylated indole alkaloids such as the brevianamides and stephacidins.
Efficient Entry to the [2.2.2]-Diazabicyclic Ring System via Diastereoselective Domino Reaction Sequence
作者:Kaila A. Margrey、Alex J. Chinn、Stephen W. Laws、Robert D. Pike、Jonathan R. Scheerer
DOI:10.1021/ol3007056
日期:2012.5.18
A domino reactionsequence involving aldol condensation, alkene isomerization, and intramolecular hetero-Diels–Alder cycloaddition for the synthesis of [2.2.2]-diazabicyclic structures is reported. Excellent diastereofacial control during the cycloaddition is enforced with a removable chiral phenyl aminal diketopiperazine substituent. The reactionsequence rapidly generates molecular complexity and
Biomimetic Total Synthesis of Malbrancheamide and Malbrancheamide B
作者:Kenneth A. Miller、Timothy R. Welch、Thomas J. Greshock、Yousong Ding、David H. Sherman、Robert M. Williams
DOI:10.1021/jo800116y
日期:2008.4.1
The biomimetic total syntheses of both malbrancheamide and malbrancheamide B are reported. The synthesis of the two monochloro species enabled the structure of malbrancheamide B to be unambiguously assigned. The syntheses each feature an intramolecular Diels−Alder reaction of a 5-hydroxypyrazin-2(1H)-one to construct the bicyclo[2.2.2]diazaoctane core, which has also been proposed as the biosynthetic
报道了 malbrancheamide 和 malbrancheamide B 的仿生全合成。两种一氯物质的合成使得 Malbrancheamide B 的结构能够被明确指定。这些合成均以 5-羟基吡嗪-2(1 H )-one 的分子内 Diels-Alder 反应为特征,以构建双环[2.2.2]二氮杂辛烷核心,这也被提议作为这些化合物的生物合成途径。