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A new irlactane-type, namely irlactin K (1), and 22 tremulane-type sesquiterpenes including fourteen previously undescribed ones, namely irpexolactins A–N (2–15), and a known irlactane-type sesquiterpenoid, were isolated from the fermentation broth of the medicinal fungus Irpex lacteus HFG1102. The structures of all the isolates were characterized by extensive spectroscopic methods, including 1D and 2D NMR and MS spectroscopic analysis. The absolute configurations of irlactin K and the known compound conocenol B (20) were established by single-crystal X-ray diffraction analysis. The vasorelaxant effects of irlactin K (1), irpexolactins A (2), C (4), K (12), and irlactam (22) were evaluated. Graphic Abstract

Four eburicane-type triterpenoids with malonyl modifications, namely irpexoates A–D (1–4), were isolated from the fruiting bodies of the medicinal fungus Irpex lacteus. The structures of the new compounds were established by extensive spectroscopic methods, including 1D and 2D NMR, HRESIMS spectroscopic analysis. Irpexoate B (2) displayed weak cytotoxicity against four human cancer cell lines (A-549, SMMC-7721, MCF-7, SW480) with IC50 values varying from 22.9 to 34.0 μM, and irpexoate D (4) showed weak cytotoxicity against the human cancer cell line SW480 with an IC50 value of 35.2 μM. Graphical Abstract Electronic supplementary material The online version of this article (10.1007/s13659-018-0160-3) contains supplementary material, which is available to authorized users.

A scale-up fermentation of the fungus Boreostereum vibrans facilitated the isolation of six new vibralactone biogenesis-associated analogues, namely vibralactamide A (1), vibralactone T (2), 13-O-lactyl vibralactone (3), 10-O-acetyl vibralactone G (4), (11R,12R)- and (11S,12R)-vibradiol (5, 6). Their structures were established via extensive spectroscopic analyses, specific optical rotation comparison, and Snatzke’s method. The biosynthetic pathway for vibralactamide A was postulated. The absolute configuration of vibralactone B was revised by single crystal X-ray diffraction analysis. This work puts the divergent vibralactone biosynthesis pathway one step further and expands the structural diversity of vibralactone-associated compounds. Graphical Abstract Electronic supplementary material The online version of this article (10.1007/s13659-017-0147-5) contains supplementary material, which is available to authorized users.

Aurantiadioic acids A (1) and B (2), two new furan-containing polyketides, and aurantoic acid A (3), a new natural product, were isolated from the liquid fermentation of the sika deer dung-derived actinomycete Actinocorallia aurantiaca. The structures of the new compounds were established by extensive spectroscopic methods, including 1D & 2D NMR, HRESIMS spectroscopic analysis. The absolute configuration of 3 was assigned by comparison of the specific optical rotations with the reported derivatives. Biological activity evaluations suggested that compounds 1–3 showed weak inhibition on NO production in the murine monocytic RAW 264.7 macrophages with IC50 values of 35.8, 41.8, 45.2 μM, respectively. Compound 3 showed weak inhibition on influenza A virus (A/PuertoRico/8/1934, H1N1) with an EC50 value of 35.9 μM, and a selective index higher than 13.3.

Six previously undescribed 5,6-seco-tremulane analogues, together with two known ones, were isolated from the culture broth of the medicinal fungus Irpex lacteus HFG1102. The structures of the new compounds were elucidated via extensive spectroscopic methods, including NMR and HRMS spectroscopic analyses. Graphical Abstract Electronic supplementary material The online version of this article (10.1007/s13659-018-0157-y) contains supplementary material, which is available to authorized users.

Two new compounds, maniesculentins A (1) and B (6), together with four known ones were isolated from the stems of Manihot esculenta Crantz. The structures of the new compounds were elucidated by extensive spectroscopic methods including NMR spectroscopy and mass spectrometry. The two new compounds (1, 6) were assayed for antibacterial activity against four tested bacteria lines. Graphical Abstract Electronic supplementary material The online version of this article (doi:10.1007/s13659-015-0052-8) contains supplementary material, which is available to authorized users.

Four new sesquiterpenoids, namely 12-hydroxy-3-oxodrimenol (1), 11-hydroxyacetoxydrim-7-en-3β-ol (2), 2,6-dimethyl-7,10-epoxy-10-hydroxymethyldodeca-2,11-dien-6-ol (3), and 7,10-epoxy-2,6,10-trimethyldodeca-2,11-diene-4,6-diol (4), along with fourteen known compounds, were isolated from the cultures of Phellinidium sulphurascens. The structures of compounds 1–4 were established on the basis of extensive spectroscopic analysis. All of them were evaluated for their cytotoxic activities. Electronic supplementary material The online version of this article (doi:10.1007/s13659-014-0047-x) contains supplementary material, which is available to authorized users.

The unusual fused β-lactone vibralactone was isolated from cultures of the basidiomycete Boreostereum vibrans and has been shown to significantly inhibit pancreatic lipase. In this study, a structure-based lead optimization of vibralactone resulted in three series of 104 analogs, among which compound C1 exhibited the most potent inhibition of pancreatic lipase, with an IC50 value of 14 nM. This activity is more than 3000-fold higher than that of vibralactone. The effect of compound C1 on obesity was investigated using high-fat diet (HFD)-induced C57BL/6 J obese mice. Treatment with compound C1 at a dose of 100 mg/kg significantly decreased HFD-induced obesity, primarily through the improvement of metabolic parameters, such as triglyceride levels. Electronic supplementary material The online version of this article (doi:10.1007/s13659-015-0062-6) contains supplementary material, which is available to authorized users.

Phytochemical reinvestigation on the cultural broth of Boreostereum vibrans led to the isolation of six new vibralactone derivatives, vibralactone N (1), vibralactone O (2), vibralactone P (3), 10-lactyl vibralactone G (4), (3S*, 4R*)-6-acetoxymethyl-2,2-dimethyl-3,4-dihydro-2H-chromene-3,4-diol (5), vibralactone Q (6). Their structures were elucidated by extensive spectroscopic methods.

Six new lanostane-type triterpenoids, namely leucocontextins S–X (1–6), together with twelve known compounds, were isolated from the fruiting bodies of Ganoderma leucocontextum. Their structures were established by MS and NMR data. Graphical Abstract Electronic supplementary material The online version of this article (doi:10.1007/s13659-016-0089-3) contains supplementary material, which is available to authorized users.