【摘 要】
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Main observation and conclusionrnSix new meroterpenoids,bipolarinoids A-F (1-6),and two known congeners (7-8) were isolated from a soil-derived fungus Bipo-laris zeicola.Their structures were elucidated based on extensive spectroscopic techniques (includi
【机 构】
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Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation,School of Pharmacy,Tongj
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Main observation and conclusionrnSix new meroterpenoids,bipolarinoids A-F (1-6),and two known congeners (7-8) were isolated from a soil-derived fungus Bipo-laris zeicola.Their structures were elucidated based on extensive spectroscopic techniques (including HRESIMS and 1D and 2D NMR data),and the absolute configurations of 1-4 were further confirmed via single-crystal X-ray diffraction analysis and comparison of experimental electronic circular dichroism (ECD) data.Structurally,compound 1 represents the first case of cochlioquinone deriva-tives featuring a formaldehyde group at C-11,and compound 3 features a rare amino group at C-11.In the immunosuppressive activ-ity assay,compounds 5-8 showed potent inhibitory activity against concanavalin A (ConA)-induced T lymphocyte proliferation with ICs0 values of 78.3,81.1,48.3,and 48.0 nmol/L,respectively,which provided promising leads for designing and developing new im-munosuppressive agents to treat auto-immunological diseases.
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