Total synthesis of the ammosamides.
The ammosamides A-C are chlorinated pyrrolo[4,3,2-de]quinoline metabolites isolated from the marine-derived Streptomyces strain CNR-698. The natural products, which possess a dense array of heteroatoms, were synthesized in 17-19 steps from 4-chloroisatin. That the five nitrogen atoms were introduced at the appropriate time and in a suitable oxidation state was key to the success of the total synthesis. Compared to synthetic deschloro ammosamide B, natural ammosamide B is much less susceptible to oxidative degradation.
Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California, San Diego, La Jolla, California 92093-0204, USA.
Chambers C
CC
Hughes
William
W
Fenical
D000577:Amides / Q000138:chemical synthesis*; D001688:Biological Products / Q000138:chemical synthesis; D006575:Heterocyclic Compounds, 3-Ring / Q000138:chemical synthesis*; D013302:Streptomyces / Q000737:chemistry*
D000577:Amides; D001688:Biological Products; D006575:Heterocyclic Compounds, 3-Ring; C534622:ammosamide A; C534623:ammosamide B; C549633:ammosamide C