0000000000006465

AUTHOR

Rudolf Hartmann

0000-0001-7807-6273

Brominated Azaphilones from the Sponge-Associated Fungus Penicillium canescens Strain 4.14.6a

The fungus Penicillium canescens was isolated from the inner tissue of the Mediterranian sponge Agelas oroides. Fermentation of the fungus on solid rice medium yielded one new chlorinated diphenyl ether (1) and 13 known compounds (2-14). Addition of 5% NaBr to the rice medium increased the amounts of 4-6, while lowering the amounts of 8, 12, and 14. Furthermore, it induced the accumulation of 17 and two new brominated azaphilones, bromophilones A and B (15 and 16). Compounds 15 and 16 are the first example of azaphilones with the connection of a benzene moiety and the pyranoquinone core through a methylene group. The structures of the new compounds were elucidated based on the 1D and 2D NMR…

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Azacoccones F-H, new flavipin-derived alkaloids from an endophytic fungus Epicoccum nigrum MK214079.

Abstract Three new flavipin-derived alkaloids, azacoccones F-H (1–3), along with six known compounds (4–9) were isolated from the endophytic fungus Epicoccum nigrum MK214079 associated with leaves of Salix sp. The structures of the new compounds were established by analysis of their 1D/2D nuclear magnetic resonance (NMR) and high-resolution electrospray ionization mass spectroscopy (HRESIMS) data. The absolute configuration of azacoccones F-H (1–3) was determined by comparison of experimental electronic circular dichroism (ECD) data with reported ones and biogenetic considerations. Epicocconigrone A (4), epipyrone A (5), and epicoccolide B (6) exhibited moderate antibacterial activity again…

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Fusaristatins D–F and (7S,8R)-(−)-chlamydospordiol from Fusarium sp. BZCB-CA, an endophyte of Bothriospermum chinense

Abstract Three new lipodepsipeptides, fusaristatins D–F (1–3) and a new α-pyrone derivative, (7S,8R)-(−)-chlamydospordiol (5), together with eight known compounds (4, 6–12) were obtained from solid rice cultures of Fusarium sp. BZCB-CA, an endophyte of the Chinese medicinal plant, Bothriospermum chinense. The planar structures of the new metabolites (1–3, 5) were established by spectroscopic techniques (1D/2D NMR and HRESIMS). Marfey’s method was applied to determine the absolute configuration of 1, while the absolute configuration of 5 was determined by single-crystal X-ray crystallography analysis in addition to Mosher’s method. Crystallographic data of inflatin C (7) are also supplied he…

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Aaptamine Derivatives from the Indonesian Sponge Aaptos suberitoides

Four new aaptamine derivatives (1-4) along with aaptamine (5) and three related compounds (6-8) were isolated from the ethanol extract of the sponge Aaptos suberitoides collected in Indonesia. The structures of the new compounds were unambiguously determined by one- and two-dimensional NMR and by HRESIMS measurements. Compounds 3, 5, and 6 showed cytotoxic activity against the murine lymphoma L5178Y cell line, with IC(50) values ranging from 0.9 to 8.3 μM.

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Secondary metabolites of the lichen-associated fungus Apiospora montagnei

Abstract The endolichenic fungus Apiospora montagnei isolated from the lichen Cladonia sp. was cultured on solid rice medium, yielding the new diterpenoid libertellenone L (1), the new pyridine alkaloid, 23-O-acetyl-N-hydroxyapiosporamide (2) and the new xanthone derivative 8-hydroxy-3-hydroxymethyl-9-oxo-9H-xanthene-1-carboxylic acid methyl ether (3) together with 19 known compounds (4–22). The structures of the new compounds were elucidated by 1D and 2D NMR spectra as well as by HRESIMS data. The absolute configuration of the new 6,7-seco-libertellenone derivative 1 was determined by single-crystal X-ray diffraction. Four additional known compounds 23–26 were isolated when NaCl or NH4Cl w…

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New 2-Methoxy Acetylenic Acids and Pyrazole Alkaloids from the Marine Sponge Cinachyrella sp.

Three new 2-methoxy acetylenic acids (1–3) and a known derivative (4), in addition to three new natural pyrazole alkaloids (5–7) were isolated from an Indonesian marine sponge of the genus Cinachyrella. Compounds 5 and 6 have previously been reported as synthetic compounds. The structures of the new compounds were established on the basis of one- and two-dimensional NMR spectroscopy as well as by mass spectrometric data. The absolute configuration of the new acetylenic acid derivatives (1–3) was established by ECD spectroscopy. All isolated compounds were evaluated for their cytotoxicity against L5178Y mouse lymphoma cells. Compounds 1–4 exhibited strong activity with an IC50 value of 0.3 µ…

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Lactones from the Sponge-Derived Fungus Talaromyces rugulosus.

The marine-derived fungus Talaromyces rugulosus isolated from the Mediterranean sponge Axinella cannabina and cultured on solid rice medium yielded seventeen lactone derivatives including five butenolides (1–5), seven (3S)-resorcylide derivatives (6–12), two butenolide-resorcylide dimers (13 and 14), and three dihydroisocoumarins (15–17). Among them, fourteen compounds (1–3, 6–16) are new natural products. The structures of the isolated compounds were elucidated by 1D and 2D NMR (Nuclear Magnetic Resonance) spectroscopy as well as by ESI-HRMS (ElectroSpray Ionization-High Resolution Mass Spectrometry). TDDFT-ECD (Time-Dependent Density Functional Theory-Electronic Circular Dichroism) calcul…

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Cytotoxic 14-Membered Macrolides from a Mangrove-Derived Endophytic Fungus, Pestalotiopsis microspora.

Seven new 14-membered macrolides, pestalotioprolides C (2), D-H (4-8), and 7-O-methylnigrosporolide (3), together with four known analogues, pestalotioprolide B (1), seiricuprolide (9), nigrosporolide (10), and 4,7-dihydroxy-13-tetradeca-2,5,8-trienolide (11), were isolated from the mangrove-derived endophytic fungus Pestalotiopsis microspora. Their structures were elucidated by analysis of NMR and MS data and by comparison with literature data. Single-crystal X-ray diffraction analysis was used to confirm the absolute configurations of 1, 2, and 10, while Mosher's method and the TDDFT-ECD approach were applied to determine the absolute configurations of 5 and 6. Compounds 3-6 showed signif…

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Ircinal E, a New Manzamine Derivative from the Indonesian Marine Sponge Acanthostrongylophora ingens

Chemical investigation of the MeOH extract of the sponge Acanthostrongylophora ingens afforded the new manzamine derivative ircinal E (1), in addition to six known metabolites (2–7). The structure of the new compound was unequivocally elucidated using one- and two-dimensional NMR spectroscopy, as well as high-resolution mass spectrometry. Compounds 1–6 exhibited strong to moderate cytotoxicity against the murine lymphoma L5178Y cell line with IC50 values ranging from 2.8 to 21.7 μM.

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New amide and dioxopiperazine derivatives from leaves of Breynia nivosa

The first chemical investigation of leaves of Breynia nivosa from Nigeria resulted in the isolation of two new amide derivatives breynivosamides A and B (1 and 2) and two new dioxopiperazine derivatives breynivosines A and B (4 and 5) together with seven known compounds (3, 6-11). The structures of the new compounds were elucidated by 1D, 2D NMR and HRESIMS data as well as by comparison with the literature. All isolated compounds were tested for the cytotoxic and antimicrobial activities. Only cristatin A (6) showed cytotoxicity against the L5178Y mouse lymphoma cell line with an IC50 value of 13.9μM while breynivosamide A (1) exhibited moderate antimicrobial activity against Mycobacterium …

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CCDC 1479852: Experimental Crystal Structure Determination

Related Article: Shuai Liu, Haofu Dai, Gamall Makhloufi, Christian Heering, Christoph Janiak, Rudolf Hartmann, Attila Mándi, Tibor Kurtán, Werner E. G. Müller, Matthias U. Kassack, Wenhan Lin, Zhen Liu, Peter Proksch|2016|J.Nat.Prod.|79|2332|doi:10.1021/acs.jnatprod.6b00473

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CCDC 1479853: Experimental Crystal Structure Determination

Related Article: Shuai Liu, Haofu Dai, Gamall Makhloufi, Christian Heering, Christoph Janiak, Rudolf Hartmann, Attila Mándi, Tibor Kurtán, Werner E. G. Müller, Matthias U. Kassack, Wenhan Lin, Zhen Liu, Peter Proksch|2016|J.Nat.Prod.|79|2332|doi:10.1021/acs.jnatprod.6b00473

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CCDC 1968535: Experimental Crystal Structure Determination

Related Article: Ni Putu Ariantari, Marian Frank, Ying Gao, Fabian Stuhldreier, Anna-Lene Kiffe-Delf, Rudolf Hartmann, Simon-Patrick Höfert, Christoph Janiak, Sebastian Wesselborg, Werner E.G. Müller, Rainer Kalscheuer, Zhen Liu, Peter Proksch|2021|Tetrahedron|85|132065|doi:10.1016/j.tet.2021.132065

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CCDC 1479850: Experimental Crystal Structure Determination

Related Article: Shuai Liu, Haofu Dai, Gamall Makhloufi, Christian Heering, Christoph Janiak, Rudolf Hartmann, Attila Mándi, Tibor Kurtán, Werner E. G. Müller, Matthias U. Kassack, Wenhan Lin, Zhen Liu, Peter Proksch|2016|J.Nat.Prod.|79|2332|doi:10.1021/acs.jnatprod.6b00473

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CCDC 1479851: Experimental Crystal Structure Determination

Related Article: Shuai Liu, Haofu Dai, Gamall Makhloufi, Christian Heering, Christoph Janiak, Rudolf Hartmann, Attila Mándi, Tibor Kurtán, Werner E. G. Müller, Matthias U. Kassack, Wenhan Lin, Zhen Liu, Peter Proksch|2016|J.Nat.Prod.|79|2332|doi:10.1021/acs.jnatprod.6b00473

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CCDC 1968536: Experimental Crystal Structure Determination

Related Article: Ni Putu Ariantari, Marian Frank, Ying Gao, Fabian Stuhldreier, Anna-Lene Kiffe-Delf, Rudolf Hartmann, Simon-Patrick Höfert, Christoph Janiak, Sebastian Wesselborg, Werner E.G. Müller, Rainer Kalscheuer, Zhen Liu, Peter Proksch|2021|Tetrahedron|85|132065|doi:10.1016/j.tet.2021.132065

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CCDC 1517632: Experimental Crystal Structure Determination

Related Article: Hao Wang, Blessing O. Umeokoli, Peter Eze, Christian Heering, Christoph Janiak, Werner E.G. Müller, Raha S. Orfali, Rudolf Hartmann, Haofu Dai, Wenhan Lin, Zhen Liu, Peter Proksch|2017|Tetrahedron Lett.|58|1702|doi:10.1016/j.tetlet.2017.03.052

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