Total synthesis of (+)-blennolide C and (+)-gonytolide C via spirochromanone
Total synthesis of (+)-blennolide C and (+)-gonytolide C via spirochromanone
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DOI：
10.1016/j.tetlet.2017.10.038
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发表时间：
2017-11-22
影响因子：
1.8
通讯作者：
Kumamoto, Takuya
中科院分区：
文献类型：
--
作者：
Adachi, Kanna;Hasegawa, Sho;Kumamoto, Takuya
本文报道了内生真菌中(+)-blennolide C和(+)-gonytolide C的不对称全合成。通过邻羟基苯乙酮和旋氧环己酮的醛醇反应，在酸性条件下进行环化，合成了手性季碳的螺旋甾酮。螺旋甾酮的烯烃部分氧化裂解生成甾酮二酯。通过Lewis酸处理双酯，通过脱保护双酯的氧官能团和同时的Dieckmann缩合，实现了(+)-blennolide C的首次全合成。（+）-gonytolide C的全合成也由去保护的二酯形成lac tone。(C) 2017 Elsevier Ltd.版权所有。
We report the asymmetric total synthesis of (+)-blennolide C and (+)-gonytolide C isolated from endophytic fungi. The synthesis involved construction of a spirochromanone with a chiral quaternary carbon by the aldol reaction of o-hydroxyacetophenones and optically active alpha-oxygenated cyclohexenone, followed by cyclization under acidic conditions. Oxidative cleavage of the alkene moiety of the spirochromanone furnished the chromanone diester. Through treating the diester with a Lewis acid, the first total synthesis of (+)-blennolide C was achieved by deprotecting the oxygen functionality of the diester and simultaneous Dieckmann condensation. Total synthesis of (+)-gonytolide C was also achieved by lac tone formation from the deprotected diester. (C) 2017 Elsevier Ltd. All rights reserved.