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A new alkaloid named aspergilalkaloid A ( 1 ) with pyridoindole hydroxymethyl piperazine dione structure along with six known compounds 2-7 were isolated from deep-sea derived fungus Aspergillus sp. HDN20-1401. The structure including absolute configuration was elucidated by extensive NMR analyses, HRESIMS, ECD calculation, and theoretical NMR calculation with DP4+ analysis. All isolated compounds were tested for antimicrobial and anticancer activity. Aspergilalkaloid A ( 1 ) showed inhibitive activity against Bacillus cereus with MIC value of 12.5  μ M and weak activity against MRCNS.

Six undescribed polyhydroxy p -terphenyls, namely asperterphenyllins A-F, were isolated from an endophytic fungus Aspergillus candidus LDJ-5. Their structures were determined by NMR and MS data. Differing from the previously reported p -terphenyls, asperterphenyllin A represents the first p -terphenyl dimer connected by a C-C bond. Asperterphenyllin A displayed anti-influenza virus A (H1N1) activity and protein tyrosine phosphatase 1B (PTP1B) inhibitory activity with IC 50 values of 53 μM and 21 μM, respectively. The anti-influenza virus A (H1N1) activity and protein tyrosine phosphatase 1B (PTP1B) inhibitory activity of p -terphenyls are reported for the first time. Asperterphenyllin G exhibited cytotoxicity against nine cell lines with IC 50 values ranging from 0.4 to 1.7 μM. Asperterphenyllin C showed antimicrobial activity against Proteus species with a MIC value of 19 μg/mL.

Three new aspochracin-type cyclic tripeptides, sclerotiotides M-O ( 1 - 3 ), together with three known analogues, sclerotiotide L ( 4 ), sclerotiotide F ( 5 ), and sclerotiotide B ( 6 ), were obtained from the ethyl acetate extract of the fungus Aspergillus insulicola HDN151418, which was isolated from an unidentified Antarctica sponge. Spectroscopic and chemical approaches were used to elucidate their structures. The absolute configuration of the side chain in compound 4 was elucidated for the first time. Compounds 1 and 2 showed broad antimicrobial activity against a panel of pathogenic strains, including Bacillus cereus , Proteus species , Mycobacterium phlei , Bacillus subtilis , Vibrio parahemolyticus , Edwardsiella tarda , MRCNS, and MRSA, with MIC values ranging from 1.56 to 25.0 µM.

Nine previously undescribed prenylated p -terphenyls, prenylterphenyllins F-J ( 1 , 2 , 4 - 6 ) and prenylcandidusins D-G ( 3 , 7 - 9 ), were isolated from an endophytic fungus, Aspergillus candidus LDJ-5. Their structures were determined from NMR and MS data. Differing from previously reported p -terphenyls, compound 3 represents a rare 6,5,6,6-fused ring system. Compounds 4 - 6 are antimicrobial, and compounds 1 , 4 , 6 , and 9 are cytotoxic.

Three new tetrahydroxanthone dimers, 5- epi -asperdichrome ( 1 ), versixanthones N ( 2 ), and O ( 3 ), were isolated from the mangrove-derived fungus Aspergillus versicolor HDN1009. Their structures, including the absolute configurations, were elucidated by NMR, HRMS, and circular dichroism (CD) experiments. Among them, compound 1 was the second example of tetrahydroxanthone dimers, which dimerized by a rare diaryl ether linkage and showed promising antibacterial activities against Vibrio parahemolyticus , Bacillus subtilis , Mycobacterium phlei , and Pseudomonas aeruginosa , with MIC values ranging from 100 μM to 200 μM; whilst compounds 2 and 3 exhibited extensive cytotoxicities against five cancer cell lines (HL-60, K562, H1975, MGC803, and HO-8910), with IC 50 values ranging from 1.7 μM to 16.1 μM.

Seven new prenylated indole diketopiperazines, versicamides A-G (1-7) and a novel chemical derivative from 7, versicamide H (8), along with three known analogic diketopiperazines (9-11) were obtained from the marine-derived fungus Aspergillus versicolor HDN08-60. Their structures were determined by spectroscopic techniques, including 2D NMR, ECD calculations, and single-crystal X-ray diffraction analysis, together with the assistance of further chemical conversions. The cytotoxicities of 1-8 were tested against the HeLa, HCT-116, HL-60, and K562 cell lines, but only 8 exhibited moderate activity against HL-60 cells, with an IC50 value of 8.7 μM. Further investigation with target screening showed that 8 exhibited selective PTK inhibitory activities.

Four new prenylated diphenyl ethers (1-4), diorcinols B-E, together with one known diorcinol (5), were obtained from the marine-derived fungus Aspergillus versicolor. Their structures were established on the basis of chemical and spectroscopic data. The absolute configurations of compounds 1 and 2 were determined by Mosher's ester and specific rotation analysis. Their cytotoxicities were evaluated using A-549, Hela, BEL-7402 and K562 cell lines. Compound 3 exhibited moderate cytotoxicities against the Hela and K562 cell lines with the IC50 values of 31.5 and 48.9 μM, respectively, and compound 4 exhibited moderate cytotoxicity only against the Hela cell line with the IC50 value of 36.5 μM.

Pyrazinopyrimidine-type alkaloids bearing a pyrazino[1,2-a] pyrimidine moiety, often have different functional groups substituted at C-8′ or C-2′/C-8′, generally further forming unique spiro-/conjugated ring systems. Four undescribed pyrazinopyrimidine-type alkaloids, including three natural products pyrasplorines A-C and an artifact deg-pyrasplorine B, as well as a biogenetically related versicoloid A were discovered from the extract of a mangrove-derived fungus Apergillus verisicolor HDN11-84. Pyrasplorine A contains unique spiral-type skeleton (composed of cyclopentenone ring with the pyrazino[1,2-a] pyrimidine core) which is unprecedented in pyrazinopyrimidine-type alkaloids. The deg-pyrasplorine B could be spontaneously converted from pyrasplorine B in mild conditions. Their structures including absolute configurations were elucidated based on NMR spectroscopic analysis, computational calculations and Marfey's method. The absolute configuration of versicoloid A was re-assigned in this study. All the isolated compounds are non-cytotoxic and deg-pyrasplorine B showed anti-influenza A virus H1N1 activity with the IC 50 of 50 μ M. [Display omitted] • Four new pyrazinopyrimidine-type alkaloids were identified. • Pyrasplorine A is the first compound with spiro-cyclopentane in pyrazinopyrimidine-type alkaloids. • The absolute configuration of compound versicoloid A was revised. • Pyrasplorine B can convert to deg-pyrasplorine B which showed anti-influenza A virus H1N1 activity. • The absolute configuration was deduced by ECD calculations and DP4+ analysis. [ABSTRACT FROM AUTHOR]

Versicamides A-F, G (III) and a chemical derivative of the latter, i.e. [ABSTRACT FROM AUTHOR]