19 research outputs found
Sargassopenillines A–G, 6,6-Spiroketals from the Alga-Derived Fungi Penicillium thomii and Penicillium lividum
Seven new 6,6-spiroketals, sargassopenillines A–G (1–7) were isolated from the alga-derived fungi Penicillium thomii KMM 4645 and Penicillium lividum KMM 4663. The structures of these metabolites were determined by HR-MS and 1D and 2D NMR. The absolute configurations of compounds 1, 5 and 6 were assigned by the modified Mosher’s method and by CD data. Sargassopenilline C (3) inhibited the transcriptional activity of the oncogenic nuclear factor AP-1 with an IC50 value of 15 µM
Virescenosides from the Holothurian-Associated Fungus Acremonium striatisporum Kmm 4401
Ten new diterpene glycosides virescenosides Z9-Z18 (1–10) together with three known analogues (11–13) and aglycon of virescenoside A (14) were isolated from the marine-derived fungus Acremonium striatisporum KMM 4401. These compounds were obtained by cultivating fungus on wort agar medium with the addition of potassium bromide. Structures of the isolated metabolites were established based on spectroscopic methods. The effects of some isolated glycosides and aglycons 15–18 on urease activity and regulation of Reactive Oxygen Species (ROS) and Nitric Oxide (NO) production in macrophages stimulated with lipopolysaccharide (LPC) were evaluated
Asperindoles A–D and a p-Terphenyl Derivative from the Ascidian-Derived Fungus Aspergillus sp. KMM 4676
Four new indole-diterpene alkaloids asperindoles A–D (1–4) and the known p-terphenyl derivative 3″-hydroxyterphenyllin (5) were isolated from the marine-derived strain of the fungus Aspergillus sp., associated with an unidentified colonial ascidian. The structures of 1–5 were established by 2D NMR and HRESIMS data. The absolute configurations of all stereocenters of 1–4 were determined by the combination of ROESY data, coupling constants analysis, and biogenetic considerations. Asperindoles C and D contain a 2-hydroxyisobutyric acid (2-HIBA) residue, rarely found in natural compounds. Asperindole A exhibits cytotoxic activity against hormone therapy-resistant PC-3 and 22Rv1, as well as hormone therapy-sensitive human prostate cancer cells, and induces apoptosis in these cells at low-micromolar concentrations
Piltunines A–F from the Marine-Derived Fungus Penicillium piltunense KMM 4668
Six new carotane sesquiterpenoids piltunines A–F (1–6) together with known compounds (7–9) were isolated from the marine-derived fungus Penicillium piltunense KMM 4668. Their structures were established using spectroscopic methods. The absolute configurations of 1–7 were determined based on circular dichroism (CD) and nuclear Overhauser spectroscopy (NOESY) data as well as biogenetic considerations. The cytotoxic activity of some of the isolated compounds and their effects on regulation of reactive oxygen species (ROS) and nitric oxide (NO) production in lipopolysaccharide-stimulated macrophages were examined