Shuchun Liu

Antifungal Metabolites from the Plant Endophytic Fungus Pestalotiopsis foedan

Pestafolide A ( 1), a new reduced spiro azaphilone derivative, and pestaphthalides A ( 2) and B ( 3), two new isobenzofuranones, have been isolated form solid cultures of an isolate of Pestalotiopsis foedan. The structures of these compounds were determined mainly by analysis of their NMR spectroscopic data. The relative configuration of 1- 3 was assigned by analysis of (1)H NMR J-values and NOESY data, and the absolute configuration was determined by application of the CD excitation chirality and modified Mosher method. Compounds 1- 3 showed modest antifungal activity.

Chloropupukeananin, the First Chlorinated Pupukeanane Derivative, and Its Precursors from Pestalotiopsis fici

Chloropupukeananin (1), the first pupukeanane chloride with highly functionalized tricyclo-[4.3.1.03,7]-decane skeleton and its possible biosynthetic precursors iso-A82775C (2) and pestheic acid (3), have been isolated from the plant endophyte Pestalotiopsis fici. The structure of 1 was determined by NMR spectroscopy and X-ray crystallography. Biogenetically, 1 could be derived from the Diels-Alder adduct of 2 and 3.

Chloropestolide A, an Antitumor Metabolite with an Unprecedented Spiroketal Skeleton from Pestalotiopsis fici

Chloropestolide A (1), a highly functionalized spiroketal with an unprecedented skeleton derived from a chlorinated bicyclo-[2.2.2]-oct-2-en-5-one ring and a 2,6-dihydroxy-4-methylbenzoic acid unit, has been isolated from the scale-up fermentation extract of Pestalotiopsis fici. The structure of 1 was elucidated by NMR spectroscopy and X-ray crystallography. 1 could be derived from the same Diels-Alder precursors as 2 and showed significant inhibitory effects on growth of two human cancer cell lines, HeLa and HT29, with GI(50) values of 0.7 and 4.2 microM, respectively.

Pestalofones A-E, bioactive cyclohexanone derivatives from the plant endophytic fungus Pestalotiopsis fici

Pestalofones A-E (1-5), five new cyclohexanone derivatives, have been isolated from cultures of the plant endophytic fungus Pestalotiopsis fici, along with the known compounds, isosulochrin (6), isosulochrin dehydrate (7), and iso-A82775C (8). The structures of 1-5 were determined by NMR spectroscopy, and the absolute configuration of 1 was assigned using the modified Mosher method. Compounds 1, 2, and 5 displayed inhibitory effects on HIV-1 replication in C8166 cells, whereas 3 and 5 showed significant antifungal activity against Aspergillus fumigatus.

Pestalotheols A-D, Bioactive Metabolites from the Plant Endophytic Fungus Pestalotiopsis theae

Pestalotheols A-D ( 1- 4 ), four new metabolites, have been isolated from cultures of an isolate of the plant endophytic fungus Pestalotiopsis theae. The structures of these compounds were determined by NMR spectroscopy, and 1 is further confirmed by X-ray crystallography. The absolute configurations of compounds 1 and 3 were assigned by application of the modified Mosher method. Pestalotheol C ( 3) displayed an inhibitory effect on HIV-1 LAI replication in C8166 cells with an EC 50 value of 16.1 microM.

Isoprenylated chromone derivatives from the plant endophytic fungus Pestalotiopsis fici.

Pestaloficiols F-L (1-7), new isoprenylated chromone derivatives including one heterodimer (7), have been isolated from a scale-up fermentation extract of the plant endophytic fungus Pestalotiopsis fici. The structures of these compounds were elucidated primarily by NMR and MS methods. The absolute configurations of 1 and 4 were assigned using the modified Mosher method. Compounds 1-3, 5, and 6 displayed inhibitory effects on HIV-1 replication in C8166 cells, whereas 4-7 showed cytotoxic activity against the human tumor cell lines HeLa and MCF7.

Photinides A-F, cytotoxic benzofuranone-derived γ-lactones from the plant endophytic fungus Pestalotiopsis photiniae.

Photinides A-F (1-6), six new unique benzofuranone-derived gamma-lactones, have been isolated from the crude extract of the plant endophytic fungus Pestalotiopsis photiniae. The structures of these compounds were elucidated primarily by NMR spectroscopy, and their absolute configurations were assigned by application of the CD excitation chirality method. Compounds 1-6 displayed modest cytotoxic effects against the human tumor cell line MDA-MB-231.

Oxepinochromenones, Furochromenone, and their Putative Precursors from the Endolichenic Fungus Coniochaeta sp.

Six new polyketides including four oxepinochromenones, conioxepinols A-D (1-4), one furochromenone, coniofurol A (5), and one xanthone, conioxanthone A (6), have been isolated from the crude extract of the endolichenic fungus Coniochaeta sp. The absolute configurations of C-7 in 1 and the 7,8-diol moiety in 3 were assigned using the modified Moshers and Snatzkes method, respectively, whereas that of C-8 in 5 was deduced via the circular dichroism data of the [Rh(2)(OCOCF(3))(4)] complex. Compounds 2-4 showed modest cytotoxicity against a small panel of human tumor cell lines.

Pestaloficiols A-E, bioactive cyclopropane derivatives from the plant endophytic fungus Pestalotiopsis fici.

Pestaloficiols A-E (1-5), five new cyclopropane derivatives, have been isolated from cultures of the plant endophyte Pestalotiopsis fici. The structures of these compounds were determined by NMR spectroscopy, and the absolute configuration of 1 was assigned using the modified Mosher method. Compounds 1, 2, and 4 displayed inhibitory effects on HIV-1 replication in C8166 cells.

Diketopiperazines from the Cordyceps-Colonizing Fungus Epicoccum nigrum

New diketopiperazines, epicoccins E-H (1-4) and diphenylalazines A (5) and B (6), have been isolated from the solid-substrate fermentation culture of the Cordyceps-colonizing fungus Epicoccum nigrum. The structures of 1-6 were determined primarily by NMR experiments, and the structure of 1 was confirmed by X-ray crystallography. The absolute configurations of 3 and 5 were assigned using the modified Mosher (3) and Marfeys (5) methods, respectively. Compounds 3-5 showed inhibitory effects on HIV-1 replication in C8166 cells.