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Eight previously undescribed metabolites including of lovastatin analogues, a pair of diastereoisomers, a cyclopentenone dimer, and three polyketides were isolated from the culture of Aspergillus terreus YIM PH30711. Two types of unprecedented skeletons, benzene-cyclopentanone complex and linear polyketide, and an unusual dimer structure were determined by spectral analysis. Compound, 3α-hydroxy-3,5-dihydromonacolin L showed moderate activity against HMG-CoA reductase, with an inhibition ratio of 34% at the concentration of 50 μM, while lovastatin and dihydromonacolin K ethyl ester presented much stronger activity against HMGR with inhibition rates of 85% and 90% at the concentration of 50 μM, respectively. Aspereusin A was active against AChE with a ratio of 62% at the concentration of 50 μM, while its stereomers did not showed obvious inhibition (<10%). The configuration at C-4 of these three diastereoisomers was crucial in the inhibition against AChE, and the β -orientation of substituted methoxyl acrylic acid should be beneficial to the combining with AChE. [ABSTRACT FROM AUTHOR]

The productions of cryptic metabolites including three undescribed drimane sesquiterpenoids, penicichrins A-C, and three known compounds from Penicillium chrysogenum were activated by the host Ziziphus jujuba medium. The structures were established by comprehensive analysis of spectroscopic data. The spiro β -lactone, and gem-dimethyl dihydroxylation in induced penicichrins A-C were rare in natural products. Cryptic metabolites, monaspurpurone was first found in Penicillium. 4-Methoxy-3-methylgoniothalamin, and 2-hydroxy-l-phenyl-l,4-pentanedione were second example of isolation. Penicichrin A, monaspurpurone, 4-methoxy-3-methylgoniothalamin, physcion, ergosterol, and ergosta-7,22-dien-3 β -ol had antifungal activities against phytopathogens, P. chrysogenum , Alternaria alternata and Aspergillus fumigatus with MICs ≤2 μg/mL, and 2-hydroxy-l-phenyl-l,4-pentanedione had flowering activity. So the chemical constituents from Z. jujuba could induce the productions of cryptic metabolites with plant growth-promoting activity from endophyte P. chrysogenum. [Display omitted] • Cryptic metabolites including three undescribed ones were found from P. chrysogenum by host medium. • The spiro β -lactone, and gem-dimethyl dihydroxylation in penicichrins were rare in natural products. • The induced compounds indicated plant growth-promoting activities. [ABSTRACT FROM AUTHOR]

A chemical investigation of the endophytic fungus Diaporthe destruens from the Hernandiaceae plant Illigera orbiculata C. Y. Wu collected from southern Yunnan Province, China, led to the isolation of six undescribed compounds, including two azaphilone analogs, which are a pair of epimers (13 R- hydroxy-chermesinone A and 13 S- hydroxy-chermesinone A); a pyrrole derivative (1-(4-(methoxymethyl)-1H-pyrrol-3-yl)ethan-1-one); an isoindolone derivative (4-hydroxy-6-methoxyisoindolin-1-one); a benzylbenzene derivative (destruensine A) and a conjectural fragment of polyketide ((2 R ,4 R)-2-(methoxymethyl)pentane-1,4-diol) along with nine known compounds. Their structures were elucidated by spectroscopic methods and HRESIMS, and the absolute configurations were further confirmed by electronic circular dichroism (ECD) and chemical derivatization. The antimicrobial activities, anti-acetylcholinesterase activities, antiproliferation, and NO production inhibitory effects of compounds 1 – 15 were evaluated. Fifteen specialised products, including six undescribed structures, were obtained from Diaporthe destruens hosted in Illigera orbiculata. Their bioactivities were evaluated. [Display omitted] • Six undescribed compounds were isolated from the fungus Diaporthe destruens. • The absolute configurations of the undescribed compounds were established. • The bioactivities of the isolated compounds were evaluated. [ABSTRACT FROM AUTHOR]