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Updated: May 15, 2026

A Fish-feeding Laboratory Bioassay to Assess the Antipredatory Activity of Secondary Metabolites from the Tissues of Marine Organisms
Published on: January 11, 2015
Placidenes G-J, Bioactive γ-Pyrone Derivatives From the Marine Mollusk Placida dendritica
Hao Wang1,2, Wen-Xuan Li2, Chao Ru1
1College of Pharmacy, Shandong University of Traditional Chinese Medicine, Jinan, China.
Abstract:
Three pairs of undescribed enantiomeric γ-pyrone derivatives placidenes G-I (1-3), together with two new congeners placidene J (4)/isoplacidene J (5) and two known compounds 6 and 7, were isolated from the marine mollusk Placida dendritica. Compounds 1a/1b-3a/3b were further separated by chiral-phase high-performance liquid chromatography. The structures were elucidated by comprehensive spectroscopic analysis, high-resolution electrospray ionization mass spectrometry, time-dependent density functional theory/electronic circular dichroism calculation, and X-ray diffraction analysis. In bioassays, compounds 1-5 exhibited moderate nitric oxide inhibition from 28.2% to 51.9% on RAW264.7 inflammatory cells at 20 µM without notable cytotoxicity.
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