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Updated: May 17, 2026

Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones
Published on: February 7, 2019
Cyclic Bis-1,3-dialkylpyridiniums from the sponge Haliclona sp
Yoonyeong Lee1, Kyoung Hwa Jang1, Ju-Eun Jeon1
1Natural Products Research Institute, College of Pharmacy, Seoul National University, San 56-1, Sillim, Gwanak, Seoul 151-742, Korea.
Abstract:
Eight novel cyclic bis-1,3-dialkylpyridiniums, as well as two known compounds from the cyclostellettamine class, were isolated from the sponge Haliclona sp. from Korea. Structures of these novel compounds were determined using combined NMR and FAB-MS/MS analyses. Several of these compounds exhibited moderate cytotoxic and antibacterial activities against A549 cell-line and Gram-positive strains, respectively. The structure-activity relationships of cyclostellettamines are discussed based on their bioactivities.
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