2026-03-12 東北大学
図1. カリブ海型シガトキシンC-CTX-1 と3位異性体の化学構造
＜関連情報＞
- https://www.tohoku.ac.jp/japanese/2026/03/press20260312-03-cctx1.html
- https://www.tohoku.ac.jp/japanese/newimg/pressimg/tohokuuniv-press20260312_03web_CCTX1.pdf
- https://pubs.acs.org/doi/10.1021/jacs.6c01247
カリブ海シガトキシンC-CTX1とそのC3-エピマーの収束的全合成 Convergent Total Synthesis of Caribbean Ciguatoxin C-CTX1 and Its C3-Epimer
Makoto Sasaki,Atsushi Umehara,Kohtaro Sugahara,Masayuki Satake,and Takeshi Tsumuraya
Journal of the American Chemical Society Published: March 9, 2026
DOI:https://doi.org/10.1021/jacs.6c01247
Abstract
Caribbean ciguatoxin C-CTX1 is a highly potent ladder-shaped polycyclic ether toxin responsible for ciguatera fish poisoning and has recently been detected beyond the Caribbean Sea region. Because of its extreme structural complexity and scarcity from natural sources, its structure and biological properties have not been fully validated by chemical means. We report here the first total synthesis of C-CTX1 and its naturally occurring C3-epimer through a convergent fragment-coupling strategy joining the ABCDE- and HIJKLMN-ring units, featuring late-stage radical cyclization and ring-closing metathesis to construct the central FG-rings. The synthesis provides definitive structural confirmation and practical milligram-scale access to both epimer. Comparative biological evaluation revealed a significant difference in relative neurotoxicity.
