New Dolabellanes from the Taiwanese Soft Coral Clavularia Inflata

Abstract

Bioassay-directed fractionation of the acetone extract of Clavularia inflata collected in Green Island has afforded two new dolabellane diterpenoids, designated as clavinflols A (4) and B (5) in addition to the reported (1R*,12R*)-dolabella-4(16),7,10-triene-3,13-dione (1), stolonidiol (2) and stolonidiol monoacetate (3). The structures of compounds 4 and 5 were determined on the basis of 1D and 2D-NMR techniques including COSY, HSQC, HMBC and NOESY experiments, and acetylation which yielded derivatives 6 and 7, respectively. Pharmacological study revealed that compounds 1-3 and 5 exhibited cytotoxicity against human oral epidermoid carcinoma (KB) cells while compound 4 showed selective activity toward human Hepa cells.

Ubiquitin-Proteasome Modulating Dolabellanes and Secosteroids from Soft Coral Clavularia flava

“…Both the MTT assay and high-content nucleus counts were performed to assess the ED 50 values of HEK293T cells expressing EGFP-UL76 for bortezomib which were 11.95 nM and 24.29 nM and for MG132 were 1.18 µM and 1.91 µM, respectively. Clavinflol B (4) showed moderate cytotoxicity in previous reports, which was consistent with our data (Table S1) [6].…”

“…Chromatographic fractionation of ethyl acetate solubles from C. flava afforded four dolabellane diterpenes, 1-4, as well as two secosteroids, 5 and 6. The three known dolabellane diterpenes, 2-4 were identified by comparison of their spectral data with those of reported literatures [5,6]. The structures of new compounds, 1, 5, and 6 were elucidated by analysis of 1D and 2D spectral data ( Figures S1-S24).…”

“…In this study, we demonstrated the identification of six compounds with proteasome inhibitory activity. Structure elucidation revealed they are dolabellane-and secosteroid-based compounds including a new dolabellane, clavinflol C (1), three known dolabellanes, stolonidiol (2), stolonidiol-17-acetate (3), and clavinflol B (4) as well as two new secosteroids, 3β,11-dihydroxy-24-methyl-9,11-secocholest-5-en-9,23-dione (5) and 3β,11-dihydroxy-24-methylene-9,11-secocholest-5-en-9,23-dione (6) (Figure 1). 3, and clavinflol B (4).…”

Comparative Analyses of Metabolomic Fingerprints and Cytotoxic Activities of Soft Corals from the Colombian Caribbean

“…According with these metabolomics results, it is important to show some studies on compounds with dolabellane skeletons obtained from different marine organisms, which have shown cytotoxic potential against different tumor cell lines, scilicet: The compound, clavirolide G, isolated from the soft coral, Clavularia viridis , collected from the Xisha Islands in the South China Sea showed moderate cytotoxic activity against KB and HL-60 cells with IC 50 values of 5.12 μg/mL and 5.92 μg/mL, respectively [33]. The compounds, clavinflols A and B, from the Clavularia inflata collected in Green Island, exhibited cytotoxicity against human oral epidermoid carcinoma (KB) cells (ED 50 = 0.35 μg/mL) and showed selective activity towards human Hepa cells (ED 50 = 1.2 µg/mL), respectively [34]. The compound, casearimene A, isolated from the species, Casearia membranacea , showed marginal activity against the tumor cell line, A549 (ED 50 > 50 µg/mL) [35].…”

A New Trinor-guaiane Sesquiterpene from an Indonesian Soft Coral Anthelia sp

“…Stolonidiol showed cytotoxicity at 1 g/mL and was identified from its 1 H NMR spectrum and specific rotation. Further chromatographic separation resulted in the isolation of the known clavinflol B [18] and a dolabellane [3], and a new minor constituent 1, whose structure ( Figure 1) is the subject of this note. hydroxyl groups.…”