The total synthesis of two decahydroquinoline poison frog alkaloids ent-cis-195A and cis-211A were achieved in 16 steps (38% overall yield) and 19 steps (31% overall yield), respectively, starting from known compound 1. Both alkaloids were synthesized from the common key intermediate 11 in a divergent fashion, and the absolute stereochemistry of natural cis-211A was determined to be 2R, 4aR, 5R, 6S, and 8aS. Interestingly, the absolute configuration of the parent decahydroquinoline nuclei of cis-211A was the mirror image of that of cis-195A, although both alkaloids were isolated from the same poison frog species, Oophaga (Dendrobates) pumilio, from Panama.
Digital Object Identifier (DOI)
The NMR spectra (1H-NMR, 13C-NMR) of all new compounds are available online.
Samples of cis-195A and cis-211A are available from the authors.
Okada, Takuya; Wu, Naizhen; Takashima, Katsuki; Ishimura, Jungoh; Morita, Hiroyuki; Ito, Takuya; Kodama, Takeshi; Yamasaki, Yuhei; Akanuma, Shin-Ichi; Kubo, Yoshiyuki; Hosoya, Ken-Ichi; Tsuneki, Hiroshi; Wada, Tsutomu; Sasaoka, Toshiyasu; Shimizu, Takahiro; Sakai, Hideki; Dwoskin, Linda P.; Hussaini, Syed R.; Saporito, Ralph A.; and Toyooka, Naoki, "Total Synthesis of Decahydroquinoline Poison Frog Alkaloids ent-cis-195A and cis-211A" (2021). Pharmaceutical Sciences Faculty Publications. 200.