CHANG-FENG DAI et al.2022-04-252022-04-25202100092673https://www.scopus.com/inward/record.uri?eid=2-s2.0-85122640023&doi=10.1246%2fbcsj.20210261&partnerID=40&md5=eb2f9d1ff24521ce204330fe13cc4074https://scholars.lib.ntu.edu.tw/handle/123456789/606344Further chemical investigation of the ethyl acetate extract of the soft coral Sarcophyton tortuosum has led to the isolation of ten terpenoidal metabolites, including six new compounds, secoditerpenes secotortuosenes A and B (1 and 2), diterpenes tortuosenes C and D (3 and 4) and tortuosumol (5), and a biscembranoid bisotortuolide cyclobutane A (6), along with four known compounds, ketoemblide (7), sartrolide G (8), emblide (9), and sarcrassin E (10). Compounds 5 and 6 are metabolites of intra- and intermolecular [2+2] cyclizations, respectively. Notably, 1 and 2 are 12-membered carbocyclic compounds possessing a 2-methyl-3-oxopentanyl side chain and representing an unprecedented molecular skeleton, while compound 6 possesses a unique cyclobutanyl biscembranoid skeleton. The absolute configurations of 1 and 5 were determined by TDDFT ECD calculations. Bioassays showed that compound 5 exhibited selective cytotoxicity against the growth of the Molt-4 cell line, while 6 exhibited inhibitory activity against P388, K562, and HT-29 cancer cell lines. Compounds 3 and 57 showed effects for inhibition toward the generation of superoxide anion, while 3, 6, and 7 displayed inhibition activity against elastase release in fMLF/CB-induced neutrophils. In addition, compounds 6, 7, and 10 exhibited anti-inflammatory activity by inhibiting nitric oxide generation in the LPS-induced RAW 264.7 cell assay. ? 2021 The Chemical Society of JapanAnti-inflammatoryCytotoxicitySarcophyton tortuosumCell cultureMusculoskeletal systemNitric oxideOlefinsAnti-inflammatoriesCembranoidsCyclizationsCyclobutanesDiterpenesEthyl-acetateMolecular skeletonSide-chainsSoft coralsMetabolites[SDGs]SDG3journal article10.1246/bcsj.202102612-s2.0-85122640023