Toward a Formal Synthesis of Laureatin: Unexpected Rearrangements Involving Cyclic Ether Nucleophiles

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• 作者：Santosh Keshipeddy ; Isamir Martı ; ́ ; nez ; Bernard F. Castillo ; II ; Martha D. Morton ; Amy R. Howell
• 刊名：The Journal of Organic Chemistry
• 出版年：2012
• 出版时间：September 21, 2012
• 年：2012
• 卷：77
• 期：18
• 页码：7883-7890
• 全文大小：483K
• 年卷期：v.77,no.18(September 21, 2012)
• ISSN：1520-6904

文摘

Laureatin, a metabolite of the red algae Laurencia nipponica, has shown potent activity as a mosquito larvicide. The two previously published syntheses of laureatin involved an initial preparation of the 8-membered cyclic ether, followed by formation of the oxetane ring. Our strategy was the reverse, i.e., to utilize an oxetane as the framework to construct the larger ring. During this work, attempted N-bromosuccinimide (NBS)-mediated cyclization of oxetane alcohol 17, prepared from readily accessible 2-methyleneoxetane 12, yielded epoxytetrahydrofuran 19 rather than the expected laureatin core. Further derivatization of 19 yielded trans fused bis-tetrahydrofuran 32. The synthesis of 19 and 32, as well as structural and stereochemical elucidation studies, are described.