0000000001308709
AUTHOR
Matthias U. Kassack
showing 14 related works from this author
Brominated Azaphilones from the Sponge-Associated Fungus Penicillium canescens Strain 4.14.6a
2019
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…
Cryptic Secondary Metabolites from the Sponge-Associated Fungus Aspergillus ochraceus
2019
The fungus Aspergillus ochraceus was isolated from the Mediterranean sponge Agelas oroides. The initial fermentation of the fungus on solid rice medium yielded 16 known compounds (4&ndash
Indole Diterpenoids from an Endophytic Penicillium sp.
2019
A chemical investigation of the endophyte Penicillium sp. (strain ZO-R1-1), isolated from roots of the medicinal plant Zingiber officinale, yielded nine new indole diterpenoids (1-9), together with 13 known congeners (10-22). The structures of the new compounds were elucidated by 1D and 2D NMR analysis in combination with HRESIMS data. The absolute configuration of the new natural products 1, 3, and 7 was determined using the TDDFT-ECD approach and confirmed for 1 by single-crystal X-ray determination through anomalous dispersion. The isolated compounds were tested for cytotoxicity against L5178Y, A2780, J82, and HEK-293 cell lines. Compound 1 was the most active metabolite toward L5178Y ce…
Alkaloids from the Sponge-Associated FungusAspergillussp.
2012
Seven new alkaloids including tryptoquivaline K (1) and fumiquinazolines K–P (2–7), bearing a rare 1-aminocyclopropane-1-carboxylic acid residue, together with six known compounds (8–13), were isolated from the fungus Aspergillus sp. obtained from the Mediterranean sponge Tethya aurantium. The structures of the new compounds were determined by extensive analysis by 1D and 2D NMR spectroscopy and mass spectrometry. The absolute configurations of tryptoquivaline K (1) and fumiquinazolines K and L (2, 3) were determined by TDDFT ECD calculations of their solution conformers, and the configurational assignment of the related fumiquinazolines M–P (4–7) was achieved by comparison of their ECD spe…
Arthrinins A–D: Novel diterpenoids and further constituents from the sponge derived fungus Arthrinium sp.
2011
Bioassay-guided fractionation of a methanolic extract of the fungus Arthrinium sp., isolated from the Mediterranean sponge Geodia cydonium, afforded 10 natural products including five new diterpenoids, arthrinins A-D (1-4) and myrocin D (5). In addition, five known compounds were obtained, which included myrocin A (6), norlichexanthone (7), anomalin A (8), decarboxycitrinone (9) and 2,5-dimethyl-7-hydroxychromone (10). The structures of all isolated compounds were unambiguously elucidated based on extensive 1D and 2D NMR and HR-MS analyzes. The absolute configuration of arthrinins A-D (1-4) was established by the convenient Mosher method performed in NMR tubes and by interpretation of the R…
In Vitro Assessment of the Genotoxic Hazard of Novel Hydroxamic Acid- and Benzamide-Type Histone Deacetylase Inhibitors (HDACi)
2020
Histone deacetylase inhibitors (HDACi) are already approved for the therapy of leukemias. Since they are also emerging candidate compounds for the treatment of non-malignant diseases, HDACi with a wide therapeutic window and low hazard potential are desirable. Here, we investigated a panel of 12 novel hydroxamic acid- and benzamide-type HDACi employing non-malignant V79 hamster cells as toxicology guideline-conform in vitro model. HDACi causing a &ge
Cytotoxic 14-Membered Macrolides from a Mangrove-Derived Endophytic Fungus, Pestalotiopsis microspora.
2016
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…
Purinergic receptors influence the differentiation of human mesenchymal stem cells
2011
Adult stem cells, including adipose tissue-derived mesenchymal stem cells (MSCs) or ectomesenchymal dental follicle cells (DFCs), attract considerable attention for their potential to differentiate into lineages, which are of major interest in the field of Regenerative Medicine. Purinergic receptors exert a wide range of biological actions in many cell and tissue types through extracellular nucleotides. Little is known about P2 receptors in adult stem cells and changes in their expression levels during differentiation. All known P2 receptors have been investigated, and a variety of P2X and P2Y receptor subtypes were detected in MSCs. Studies investigating intracellular calcium levels on rec…
Cyclic heptapeptides from the soil-derived fungus Clonostachys rosea
2019
Abstract Three new cyclic heptapeptides (1–3) together with three known compounds (4–6) were isolated from a solid rice culture of the soil-derived fungus Clonostachys rosea. Fermentation of the fungus on white beans instead of rice afforded a new γ-lactam (7) and a known γ-lactone (8) that were not detected in the former extracts. The structures of the new compounds were elucidated on the basis of 1D and 2D NMR spectra as well as by HRESIMS data. Compounds 1 and 4 exhibited significant cytotoxicity against the L5178Y mouse lymphoma cell line with IC50 values of 4.1 and 0.1 µM, respectively. Compound 4 also displayed cytotoxicity against the A2780 human ovarian cancer cell line with an IC50…
CCDC 1479852: Experimental Crystal Structure Determination
2016
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
CCDC 1862565: Experimental Crystal Structure Determination
2019
Related Article: Ni P. Ariantari, Elena Ancheeva, Chenyin Wang, Attila Mándi, Tim-O. Knedel, Tibor Kurtán, Chaidir Chaidir, Werner E. G. Müller, Matthias U. Kassack, Christoph Janiak, Georgios Daletos, Peter Proksch|2019|J.Nat.Prod.|82|1412|doi:10.1021/acs.jnatprod.8b00723
CCDC 1479853: Experimental Crystal Structure Determination
2016
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
CCDC 1479850: Experimental Crystal Structure Determination
2016
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
CCDC 1479851: Experimental Crystal Structure Determination
2016
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