A New Sterol-Related Metabolite from the Soft Coral Capnella imbricata

Exploratory research was carried out on the ethyl acetate extract derived from the soft coral Capnella imbricata, sourced from the southeastern waters of Taiwan. This investigation yielded the isolation of three sterol-related compounds (1–3). Among these compounds, one previously unidentified metabolite, designated as 4β-hydroxy-24-methylene-5-cholesten-7-one (1), was discovered, along with two known metabolites, namely, 3β-hydroxy-24-methylene-5-cholesten-7-one (2) and gorgostan-5,25-dien-3β-ol (3). The structures of these isolated metabolites were determined through comprehensive spectroscopic analyses. Furthermore, the relative stereochemistry of metabolite 3 was established for the first time in this study using single-crystal X-ray diffraction analysis. The potential anti-inflammatory properties of metabolites 1–3 were evaluated by investigating their ability to suppress the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) proteins in lipopolysaccharide (LPS)-induced RAW 264.7 macrophage cells.