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Blapsols A–D ( 1 – 4 ), four new compounds possessing a 2,3-dihydrobenzo[ b ][1,4]dioxin group, together with five known N -acetyldopamine dimers ( 5 – 9 ), were isolated from Blaps japanensis . Their structures including the absolute configuration of (+)- 1 were determined by means of spectroscopic and X-ray crystallographic methods. Chiral HPLC was used to separate (−)- and (+)-enantiomers of compounds 1 – 4 , which were isolated from this insect as racemic mixtures. All the compounds were found to have inhibitory effects towards COX-2 with IC 50 values in the range of 1.3–17.8 μM. [ABSTRACT FROM AUTHOR]

Abstract: Four dihydrothiophene-condensed chromones including two new compounds oxalicumones D–E (1–2) and known oxalicumones A–B (3–4), along with five other known chromones were isolated from a culture broth of the marine gorgonian-associated fungus Penicillium oxalicum SCSGAF 0023. The structures of 1–2 were elucidated by spectroscopic analysis. Eleven derivatives 3a–3i and 4a–4b were obtained from the acylation of 3 and 4, respectively. Compounds 1–4, 3a–3e, 3g–3h, and 4b showed significant cytotoxicity against several carcinoma cell lines with IC50 ⩽10μM. And their structure–bioactivity relationship was discussed. [Copyright &y& Elsevier]