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Three unusual sesterterpenoids featuring unprecedented rearranged colquhounane (C25) and tetranorcolquhounane (C21) frameworks, colquhounoids E (1) and F (3) and norcolquhounoid F (2), were isolated from a Lamiaceae medicinal plant Colquhounia coccineavar. mollis. Their structures were elucidated by spectroscopic analysis and quantum chemical calculations. A biomimetic inspired regioselective cyclopropane cleavage was achieved under acidic conditions. The immunosuppressive activities of these new sesterterpenoids were also evaluated.

Eleven triterpene acids including 10 new compounds (kadcoccinic acids A–J, 1–10) were isolated from the stems of Kadsura coccinea. Except for 10, these compounds feature a rearranged lanostane skeleton with a 6/6/5/6 tetracyclic ring system, and compounds 1and 2are the first examples of 2,3-seco-6/6/5/6-fused tetracyclic triterpenoids. Their structures were established primarily by spectroscopic and spectrometric methods. Additionally, the absolute configuration of 3was determined by single-crystal X-ray diffraction. Several of the compounds isolated were tested for their anti-HIV-1 and cytotoxic activities.

A new cytotoxic and antiviral cyclic tetrapeptide, asperterrestide A (1), a new alkaloid, terremide C (2), and a new aromatic butenolide, aspernolide E (3), together with 10 known compounds were isolated from the fermentation broth of the marine-derived fungus Aspergillus terreusSCSGAF0162. Their structures were elucidated by spectroscopic analysis, and the absolute configuration of 1was determined by the Mosher ester technique and analysis of the acid hydrolysates using a chiral-phase HPLC column. Compound 1contains a rare 3-OH-N-CH3-Phe residue and showed cytotoxicity against U937 and MOLT4 human carcinoma cell lines and inhibitory effects on influenza virus strains H1N1 and H3N2.