Department of Chemistry, Faculty and Graduate School of Science, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan.
Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikeneyama, Toyonaka, Osaka, 560-0043, Japan.
Angew Chem Int Ed Engl. 2018 May 22;57(21):6060-6064. doi: 10.1002/anie.201712167. Epub 2018 Apr 27.
Amphidinol 3 (AM3) is a marine natural product produced by the dinoflagellate Amphidinium klebsii. Although the absolute configuration of AM3 was determined in 1999 by extensive NMR analysis and degradation of the natural product, it was a daunting task because of the presence of numerous stereogenic centers on the acyclic carbon chain and the limited availability from natural sources. Thereafter, revisions of the absolute configurations at C2 and C51 were reported in 2008 and 2013, respectively. Reported herein is the revised absolute configuration of AM3: 32S, 33R, 34S, 35S, 36S, and 38S based on the chemical synthesis of partial structures corresponding to the C31-C67 fragment of AM3 in combination with degradation of the natural product. The revised structure is unique in that both antipodal tetrahydropyran counterparts exist on a single carbon chain. The structural revision of AM3 may affect proposed structures of congeners related to the amphidinols.
Amphidinol 3（AM3）是一种海洋天然产物，由腰鞭毛藻属（Dinoflagellate）的 Amphidinium klebsii 产生。尽管 AM3 的绝对构型已于 1999 年通过广泛的 NMR 分析和天然产物的降解确定，但由于在非环碳链上存在许多手性中心以及天然来源的有限可用性，这仍然是一项艰巨的任务。此后，2008 年和 2013 年分别报道了 C2 和 C51 处绝对构型的修订。本文报道了 AM3 的修订绝对构型：32S、33R、34S、35S、36S 和 38S，基于 AM3 的 C31-C67 片段的部分结构的化学合成以及天然产物的降解。修订后的结构是独特的，因为在单个碳链上存在两个对映体的四氢吡喃。AM3 的结构修订可能会影响与 Amphidinols 相关的同系物的建议结构。
