Atranones and dolabellanes with cardiomyocyte protective activity against cold ischemic injury from a coral-associated fungus Stachybotrys chartarum.

Five undescribed atranones, namely atranones V-Z (1-5), three undescribed dolabellane-type diterpenoids, namely stachatranones D-F (7-9), together with four known congeners (6 and 10-12), were obtained from a coral-associated strain of the toxigenic fungus Stachybotrys chartarum. Their structures were elucidated via extensive spectroscopic analyses, mainly including the HRESIMS and NMR data, single-crystal X-ray diffraction analysis, electronic circular dichroism calculation, and [Mo(OAc)] induced circular dichroism spectrum. The cardiomyocyte protective activity assay revealed that compound 9 significantly ameliorated cold ischemic injury at 24 h post cold ischemia (CI) in a dose-dependent manner.

Discovery of novel natural cardiomyocyte protectants from a toxigenic fungus Stachybotrys chartarum.

Stachybatranones A-F (1a/1b and 2-6) and three known analogues, namely methylatranones A and B (7 and 8) and atranone B (9), were isolated and identified from a toxigenic fungus Stachybotrys chartarum. Their structures and absolute configurations were elucidated via the extensive spectroscopic data, comparison of the experimental electronic circular dichroism (ECD) data, and single-crystal X-ray diffraction analyses. Structurally, compounds 2-6 belonged to a rare class of C-alkylated dolabellanes, featuring a unique five-membered hemiketal ring and a γ-butyrolactone moiety both fused to an 11-membered carbocyclic system, while compound 1 (1a/1b) represented the first example of a 5-11-6-fused atranone possessing a 2,3-butanediol moiety.

Two new lanostane-type triterpenoids from the fungus sp. TJ403-rc01.

The endophytic fungus sp. TJ403-rc01 (Dematiaceae) isolated from the leaves of Jacq. (Rosaceae) was cultivated on rice medium and chemically investigated, affording two new lanostane-type triterpenoids, namely pericinones A and B ( and ).

Asperanstinoids A-E: Undescribed 3,5-dimethylorsellinic acid-based meroterpenoids from Aspergillus calidoustus.

Large-scale culture is a complementary and practical method for genome mining and OSMAC approaches to discover novel natural products through accumulation and reprocessing effects. By employing a large-scale culture approach, twelve 3,5-dimethylorsellinic acid (DMOA)-based meroterpenoids, including five undescribed compounds, namely asperanstinoids A-E, were obtained from fungus Aspergillus calidoustus, which was isolated from the wetland soil collected at Dianchi Lake, Yunnan Province. The structures and absolute configurations of asperanstinoids A-E were determined by various spectroscopic analyses, including NMR spectroscopy, high-resolution electrospray ionization mass spectrometry (HRESIMS), single-crystal X-ray diffraction, and electronic circular dichroism (ECD) calculations, and the absolute configurations of three known compounds, dehydroaustinol, austinol, and austin, were confirmed via single-crystal X-ray diffraction for the first time.

A new pair of cytotoxic enantiomeric isoprenylated chromone derivatives from sp.

A new pair of enantiomeric isoprenylated chromone derivatives, (±)-pestaloficiol X [(±)-], along with a known compound pestaloficiol J (), were isolated from the plant endophytic fungus sp. The racemic mixture was separated through chiral HPLC. The structures of new compounds (±)- were elucidated on the basis of extensive spectroscopic data and their absolute configurations were further configured through computational analysis of their electronic circular dichroism (ECD) spectra.

Bioassay-Directed Isolation of Antibacterial Metabolites from an Arthropod-Derived .

Bioassay-directed isolation of secondary metabolites from an extract of TJ403-CA4 isolated from the medicinally valuable arthropod afforded five new and 10 known compounds (-). All the compounds (except ) belong to a minor class of highly rigid 6-5-5-5-fused tetracyclic cyclopiane-type diterpenes known to be exclusively produced by members of the genus. The structures and absolute configurations of the new compounds (-) were elucidated by extensive spectroscopic analyses, including HRESIMS and 1D and 2D NMR, single-crystal X-ray diffraction, and comparison of the experimental electronic circular dichroism data.

Modified Fusicoccane-Type Diterpenoids from .

Seven new modified fusicoccane-type diterpenoids (-), together with two known congeners ( and ), were obtained from . Their structures were elucidated from a combination of NMR and HRESIMS data and C NMR calculation as well as DP4+ probability analyses, and the absolute configurations of - were determined by ECD calculation and single-crystal X-ray diffraction (Cu Kα). Compounds - belong to a rare class of 16--dicyclopenta[]cyclooctane diterpenoids, and compounds and represent the first examples of fusicoccane-type diterpenoids featuring two previously undescribed tetracyclic 5/6/6/5 ring systems, while compound features a previously undescribed tetracyclic 5/8/5/3 ring system.

Fusicoccane-derived diterpenoids with bridgehead double-bond-containing tricyclo[9.2.1.0]tetradecane ring systems from Alternaria brassicicola.

Fusicoccane-derived diterpenoids bearing a unique bridgehead double-bond-containing tricyclo[9.2.1.

Structurally diverse and bioactive alkaloids from an insect-derived fungus Neosartorya fischeri.

Seven undescribed alkaloids, namely fischeramides A and B, 5,6-dimethoxycircumdatin C, 6-hydroxyacetylaszonalenin, 3-methoxyglyantrypine, 9-methoxyfumitremorgin C, and spirotryprostatin M, one undescribed natural product, namely 11-deacetyl pyripyropene A, together with nine known congeners, were isolated from the solid cultures of fungus Neosartorya fischeri, which was separated from a medicinal insect Cryptotympana atrata. Their structures were elucidated by extensive spectroscopic data, electronic circular dichroism (ECD) calculations, and single-crystal X-ray diffraction analyses. Structurally, fischeramides A and B represented a pair of rare geometric isomers of the benzodiazepinedione derivatives with a highly conjugated feature.

Reisolation and Configurational Reinvestigation of Cottoquinazolines E-G from an Arthropod-Derived Strain of the Fungus .

The reported fumiquinazoline-related alkaloids cottoquinazolines E-G (-) were reisolated from solid cultures of the fungus , which was isolated from the medicinal arthropod . The unresolved issues regarding the absolute configurations (for cottoquinazolines E and F) prompted a reinvestigation of the configurations for all three compounds, as enabled by extensive spectroscopic methods, comparisons of experimental electronic circular dichroism data, and X-ray crystallography. In addition, cottoquinazoline F () showed significant antibacterial activity against ESBL-producing , , , and with MIC values of 8, 32, 32, and 16 μg/mL, respectively.

Alterbrassinoids A-D: Fusicoccane-Derived Diterpenoid Dimers Featuring Different Carbon Skeletons from .

Alterbrassinoids A-D (-), the first examples of fusicoccane-derived diterpenoid dimers furnished by forming an undescribed C-12-C-18' linkage, were isolated from modified cultures of . Compounds and represent unprecedented heterodimers, whereas and represent unprecedented homodimers, and also features an undescribed anhydride motif. Their structures were assigned via spectroscopic methods, electronic circular dichroism calculations, and single-crystal X-ray diffraction.

HPLC-DAD-Directed Isolation of Linearly Fused Prenylated Indole Alkaloids from a Soil-Derived .

An HPLC-DAD-directed chemical investigation of the soil-derived fungus QC812 resulted in the isolation and identification of eight new linearly fused prenylated indole alkaloids, asperversiamides I-P (-), along with a congener, asperversiamide H (). Their structures and absolute configurations were determined by spectroscopic analysis including HRESIMS and 1D and 2D NMR, electronic circular dichroism analysis, and single-crystal X-ray diffraction. Asperversiamide I (), the first diketopiperazine derived from d-proline and l-tryptophan, possesses an unprecedented C-11-spiro-fused 6/6/5/5/6/5 hexacyclic ring system.

Antimicrobial Dolabellanes and Atranones from a Marine-Derived Strain of the Toxigenic Fungus .

Three new dolabellane-type diterpenoids (-) and three new atranones (-) were isolated and identified from a marine-derived strain of the toxigenic fungus . The planar and relative structures of - were elucidated using extensive spectroscopic methods, and their absolute configurations were fully confirmed via single-crystal X-ray diffraction analysis. Structurally, compounds and have a 1,14- dolabellane-type diterpenoid skeleton; compound is the first C atranone featuring a propan-2-one motif linked to a dolabellane-type diterpenoid by a carbon-carbon bond; compound represents the first example of a C atranone with a 2-methyltetrahydrofuran-3-carboxylate motif fused to a dolabellane-type diterpenoid at C-5-C-6.

Mycophenolic Acid Derivatives with Immunosuppressive Activity from the Coral-Derived Fungus .

Mycophenolic acid (MPA) is a potent inosine-5′-monophosphate dehydrogenase (IMPDH) inhibitor for immunosuppressive chemotherapy. Most importantly, as the 2-morpholinoethyl ester prodrug of MPA, mycophenolate mofetil (MMF) is a well-known immunosuppressant used to prevent rejection in organ transplantations. Nevertheless, due to its frequently occurred side effects, searching for new therapeutic agents is ongoing.

A New Breviane Spiroditerpenoid from the Marine-Derived Fungus Penicillium sp. TJ403-1.

Marine-derived fungi are a promising and untapped reservoir for discovering structurally interesting and pharmacologically active natural products. In our efforts to identify novel bioactive compounds from marine-derived fungi, four breviane spiroditerpenoids, including a new compound, brevione O (), and three known compounds breviones I (), J (), and H (), together with a known diketopiperazine alkaloid brevicompanine G (), were isolated and identified from an ethyl acetate extract of the fermented rice substrate of the coral-derived fungus sp. TJ403-1.