Imidazole Alkaloids and Their Zinc Complexes from the Calcareous Marine Sponge Leucetta chagosensis.

Abstract

Five new imidazole derivatives (1-5), together with eight related known alkaloids, were isolated from a calcareous marine sponge, Leucetta chagosensis, collected from the South China Sea. Their structures were fully characterized by spectroscopic methods. Structurally, 1 possesses an unusual skeleton featuring imidazole and oxazolone rings linked via a nitrogen atom, whereas 2 bears an intriguing guanylurea-substituted imidazole ring. Compounds 4 and 5 were identified as zinc complexes; they represent the metal complex analogues of naamidine J (6) and pyronaamidine (7), respectively. Among the isolated compounds, 2 and 5 showed significant inhibitory activities toward the LPS-induced production of IL-6 in the human acute monocytic leukemia cell line THP-1, and 7 displayed cytotoxicity against MCF-7, PC9, A549, and breast cancer stem cells (MCF-7-Oct4-GFP) with IC50 values of 5.2, 5.6, 7.8, and 10 μM, respectively.

• Authors: Wei-Zhuo Tang, Zhong-Zhen Yang, Wei Wu, Jie Tang, Fan Sun, Shu-Ping Wang, Chun-Wei Cheng, Fan Yang, Hou-Wen Lin
• Journal: Journal of natural products (J Nat Prod) Vol. 81 Issue 4 Pg. 894-900 (04 27 2018) ISSN: 1520-6025 [Electronic] United States
• PMID: 29648818 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Alkaloids
• Antifungal Agents
• Imidazoles
• Interleukin-6
• imidazole
• Zinc

Topics

• A549 Cells
• Alkaloids (pharmacology)
• Animals
• Antifungal Agents (pharmacology)
• Cell Line, Tumor
• China
• Humans
• Imidazoles (pharmacology)
• Interleukin-6 (metabolism)
• MCF-7 Cells
• Porifera (chemistry)
• THP-1 Cells
• Zinc (metabolism)