Tridiscorhabdin and Didiscorhabdin, the First Discorhabdin Oligomers Linked with a Direct C–N Bridge from the Sponge Latrunculia biformis Collected from the Deep Sea in Antarctica

• Published in: Journal of Natural Products
• Main Authors: Li, Fengjie, Pandey, Pankaj, Janussen, Dorte, Chittiboyina, Amar G., Ferreira, Daneel, Tasdemir, Deniz
• Format: Article in Journal/Newspaper
• Language: English
• Published: ACS (American Chemical Society) 2020
• Subjects: Weddell; Weddell Sea; Antarc*; Antarctica; Antarctica Journal
• Online Access: https://oceanrep.geomar.de/id/eprint/49482/; https://oceanrep.geomar.de/id/eprint/49482/1/acs.jnatprod.0c00023.pdf; https://oceanrep.geomar.de/id/eprint/49482/2/np0c00023_si_001.pdf; https://doi.org/10.1021/acs.jnatprod.0c00023

Guided by LC-MS/MS molecular networking-based metabolomics and cytotoxic activity, two new discorhabdin-type alkaloids, tridiscorhabdin (1) and didiscorhabdin (2), were isolated from the sponge Latrunculia biformis, collected from the Weddell Sea (Antarctica) at -291 m depth. Their structures were established by HRESIMS, NMR, [α]D, and ECD data coupled with DFT calculations. Both compounds bear a novel C-N bridge (C-1/N-13) between discorhabdin monomers, and 1 represents the first trimeric discorhabdin molecule isolated from Nature. Tridiscorhabdin (1) exhibited strong cytotoxic activity against the human colon cancer cell line HCT-116 (IC50 value 0.31 μM).