Two unprecedented cembrene-type terpenes from an indonesian soft coral sarcophyton sp.

Two unusual cembranoids, sarcofuranocembrenolides A (1) and B (2), were isolated from a soft coral Sarcophyton sp. together with five known cembranoids (3–7). Compound 1 had a unique carbon skeleton of 8,19-bisnorfuranocembrenolide. Compound 2 was a furanocembrenolide, but a C1 unit (C-20) was attached to C-10 instead of C-12 of the ordinary cembrenolides. These rearrangements are unique in the biosynthesis of cembranoid diterpenes. Lobohedleolide (5), (7Z)-lobohedleolide (6), and denticulatolide (7) inhibited the colony formation of V79 cells at ED50 values of 4.6 (abt. 1.52), 3.7 (1.22), and 3.6 (1.40) μM (μg/mL), respectively, and reduced TNF-α production from LPS-stimulated RAW264.7 cells at 3.0–10.0 μM.