Total synthesis and structural revision of vannusals A and B: synthesis of the originally assigned structure of vannusal B.
Total synthesis and structural revision of vannusals A and B: synthesis of the originally assigned structure of vannusal B.
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DOI：
10.1021/ja100740t
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发表时间：
2010-05-26
影响因子：
15
通讯作者：
Lizos, Dimitrios E.
中科院分区：
文献类型：
--
作者：
Nicolaou, K. C.;Ortiz, Adrian;Zhang, Hongjun;Dagneau, Philippe;Lanver, Andreas;Jennings, Michael P.;Arseniyadis, Stellios;Faraoni, Raffaella;Lizos, Dimitrios E.
The total synthesis of the originally assigned structure of vannusal B (2) and its diastereomer (d-2) are described. Initial forays into these structures with model systems revealed the viability of a metathesis-based approach and a SmI2-mediated strategy for the key cyclization to forge the central region of the molecule, ring C. The former approach was abandoned in favor of the latter when more functionalized substrates failed to enter the cyclization process. The successful, devised convergent strategy based on the SmI2-mediated ring closure utilized vinyl iodide (−)-26 and aldehyde fragment (±)-86 as key building blocks, whose lithium-mediated coupling led to isomeric coupling products (+)-87 and (−)-88. These intermediates were separately converted to precursors (+)-25 and (−)-97, which cyclized under the influence of SmI2–HMPA to afford products (−)-90/(−)-91 and (+)-98, respectively. The former two intermediates were converted to vannusal B structure 2 while the latter gave rise to its diastereomeric structure d-2, neither of which exhibited the reported spectroscopic data of the natural product. These investigations led to the discovery and development of a number of new synthetic technologies that set the stage for the solution of the vannusal structural conundrum.
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影响因子：
15
作者：
Nicolaou, K. C.;Ortiz, Adrian;Zhang, Hongjun;Guella, Graziano
通讯作者：
Guella, Graziano
影响因子：
16.6
作者：
Nicolaou, K. C.;Zhang, Hongjun;Dagneau, Philippe
通讯作者：
Dagneau, Philippe
影响因子：
16.6
作者：
Nicolaou, K. C.;Zhang, Hongjun;Ortiz, Adrian
通讯作者：
Ortiz, Adrian
影响因子：
3.6
作者：
GRIECO, PA;NISHIZAWA, M
通讯作者：
NISHIZAWA, M
影响因子：
15
作者：
ARHART, RJ;MARTIN, JC
通讯作者：
MARTIN, JC