Four new polyketide synthase-nonribosomal peptide synthetase (PKS-NRPS) hybrid metabolites, pericoannosin A (1), with an unusual hexahydro-1H-isochromen-5-isobutylpyrrolidin-2-one skeleton, and three cytochalasans, periconiasins D-F (2-4), were isolated from the endophytic fungus Periconia sp. F-31. Their structures and absolute configurations were elucidated through extensive spectroscopic analyses, calculated ECD, and single-crystal X-ray diffraction (Cu Kα). A possible biogenetic pathway is proposed. Compounds 1 and 4 showed anti-HIV activity with IC50s of 69.6 and 29.2 μM, respectively.

Thirty-three metabolites including five phenalenone derivatives (1-5), seven cytochalasins (6-12), thirteen butenolides (13-25), and eight phenyl derivatives (26-33) were isolated from Aspergillus sp. CPCC 400735 cultured on rice. The structures of all compounds were elucidated by NMR, MS, and CD experiments, of which 1-5 (asperphenalenones A-E), 6 (aspochalasin R), and 13 (aspulvinone R) were identified as new compounds. Specifically, asperphenalenones A-E (1-5) represent an unusual structure composed of a linear diterpene derivative linked to a phenalenone derivative via a C-C bond. Compounds 1, 4, 10, and 26 exhibited anti-HIV activity with IC values of 4.5, 2.4, 9.2, and 6.6 μM, respectively (lamivudine 0.1 μM; efavirenz, 0.4 × 10 μM).

Periconiasins A-C (1-3), new cytochalasans with an unprecedented 9/6/5 tricyclic ring system, were isolated from the endophytic fungus Periconia sp. F-31. Their structures and absolute configurations were elucidated by extensive spectroscopic and X-ray crystallographic analyses. Their biosynthesis is proposed to occur from an unusual seven acetate/malonate polyketide backbone attached to one leucine moiety by a PKS-NRPS followed by Diels-Alder and other reactions. 1 and 2 showed significant cytotoxicity against human HCT-8 cancer cells.

Periconianone A (1), a polyoxygenated sesquiterpenoid with a new 6/6/6 tricarbocyclic skeleton, and periconianone B (2) were isolated from the endophytic fungus Periconia sp. Their structures and absolute configurations were elucidated by extensive spectroscopic analyses, calculated ECD, and single-crystal X-ray diffraction (Cu Kα). The biosynthesis of the unusual six-membered carbonic ring of 1 was postulated to be formed through intramolecular aldol condensation. Compounds 1 and 2 showed significant neural anti-inflammatory activity.

Nine new polyoxygenated eremophilane sesquiterpenes, periconianones C-K (1-9), including one unusual isoeremophilane sesquiterpene, periconianone C (1), and four trinor-eremophilane sesquiterpenes, periconianones H-K (6-9), were isolated from the endophytic fungus Periconia sp. F-31. Compound 1 is the first furan-type isoeremophilane reported containing a linkage of C-8/C-11 and a 7,12-epoxy moiety. These compound structures, including absolute configurations, were elucidated through extensive spectroscopic data analysis, electronic circular dichroism, Mo2(AcO)4-induced circular dichroism, and single-crystal X-ray diffraction (Cu Kα). Compounds 2, 5, and 9 showed inhibition effects on lipopolysaccharide-induced NO production in BV2 cells by 10.2%, 18.3%, and 16.1% at a concentration of 1.0 μM, respectively, which is comparable to the positive control curcumin (12.9% at 1.0 μM).