Two new compounds from the Hainan Soft Corals Sinularia tumulosa and Sinularia depressa with their anti-inflammatory or cytotoxic activities

Oxygenated Cembrane Diterpenes from the South China Sea Soft Coral Sinularia tumulosa**

“…Moreover, the absolute configuration of 1 was determined by the TDDFT ECD technique, while the relative configuration of 2 was assigned via the QM-NMR calculations. Contrasting to the two previous studies, [16,17] this is the first report demonstrating the existence of cembrane diterpenes in the title species. And it is interesting to notice that the chemical profiles of soft coral S. tumulosa from different waters are different, which indicates the geographical influence on the metabolic process of S. tumulosa.…”

“…Freshly collected animals of S. tumulosa were immediately put at À 20 °C, and kept frozen before they were exhaustively extracted by acetone. The usual workup [16,17] of the Et 2 O-soluble fraction of the acetone extract of the S. tumulosa yielded five secondary metabolites (1-5) (Figure 1). Among them, three known isolates were readily identified as (+)-(7S,8S)-epoxy-7,8dihydrocembrene C (3), [18] (À )-sarcophytol-A (4), [19] gibberosene G (5), [20] respectively, by the comparison of their NMR data and specific optical rotation [α] D values with those reported in the literature.…”

“…Till now, there has been only two reports of the chemical constituents of the title species, both of which were carried out by our group previously before this work. In these two studies, both specimens were collected in Ximao Island, South China Sea, and a batch of terpenes [16] and steroids [17] with diverse architectures and significant anti-inflammatory [16,17] and cytotoxic [17] activities have been found. Inspired by our previous work, the sample collected off the Lingshui Bay, South China Sea was studied, which was geographically different from the two aforementioned ones.…”