Cytotoxic cholesta-1,4-dien-3-one derivatives from soft coral Nephthea sp.

Five new steroids, (12β, 22R)-12-acetoxy-22-hydroxy-cholesta-1,4-dien-3-one (1), (12β, 22R)-12-hydroxy-22-acetoxy-cholesta-1, 4-dien-3-one (2), (12β, 22R)-12, 22-diacetoxy-cholesta-1, 4-dien-3-one (3), (22R)-18, 22-diacetoxy-cholesta-1, 4-dien-3-one (4), (20R, 22R)-20-hydroxy-22-acetoxy-cholesta-1, 4-dien-3-one (5), and one known steroid astrogorgol N (6), were isolated from soft coral Nephthea sp. Their structures were established by spectroscopic analysis (1D, 2D NMR, HRMS) and comparisons of their spectral data with those of related steroids. The absolute configuration at C-22 of 1 was determined to be R by Mosher’s analysis. All isolated compounds exhibited cytotoxic activity against HeLa cells with IC50 values ranged from 7.51 ± 0.22 to 18.72 ± 0.78 μg/mL.

Figure optionsDownload as PowerPoint slideHighlights
► Five new cholesta-1, 4-dien-3-one derivatives were isolated from soft coral Nephthea sp.
► Their structures were elucidated by 1D, 2D NMR spectra, HRMS, and Mosher’s analysis.
► All isolated compounds exhibited moderate cytotoxicity against HeLa cells.