First synthesis of the difuransesquiterpene athanasin and the elucidation of its relative and absolute configuration
摘要:
The synthesis of the naturally occurring difuransesquiterpene athanasin is described. Employing Seebach's method of ''self-reproduction of chirality'', the chiral oxirane 6 is built up, which is successively connected with suitable furan building blocks. Cyclization of the resulting diols 14 a/b gives the enantiomerically pure diastereomers 1a and 1b.Comparison of their spectroscopic data with athanasin after separation allows the elucidation of the natural product's relative and absolute configuration.
Enantioselective Synthesis of (−)-(<i>R</i>)-Cordiachromene and (−)-(<i>R</i>)-Dictyochromenol Utilizing Intramolecular<i>S</i><sub>N</sub>Ar Reaction
作者:Yoshihiro Noda、Misato Yasuda
DOI:10.1002/hlca.201200312
日期:2012.10
A simple and efficient enantioselectivesynthesis of chromene, (−)‐(R)‐cordiachromene (1), and (−)‐(R)‐dictyochromenol (2) has been accomplished. This convergent synthesisutilizes intramolecular SNAr reaction for the formation of chroman ring, and Seebach's method of ‘self‐reproduction of chirality’ should establish the (R)‐configuration of the C(2) side chain as key steps.
一个简单而有效的对苯二酚,(-)-(R)-cordiachromene(1)和(-)-(R)-dictyochromenol(2)的对映选择性合成已经完成。这种聚合合成利用分子内的S N Ar反应形成苯并二氢吡喃环,Seebach的“手性自我复制”方法应将C(2)侧链的(R)-构型确立为关键步骤。
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