ABSTRACT
Two polyketides containing an α-pyrone unit, named penicyrones A (1) and B (2), were isolated from a culture broth of the marine-derived Penicillium sp. TPU1271 together with nine known compounds: verrucosidin (3), fructigenine A (4), verrucofortine (5), cyclo-(L-Trp-L-Phe) (6), cyclopenol (7), cyclopenin (8), penipratynolene (9), aspterric acid (10) and viridicatol (11). The structures of 1 and 2 were elucidated by analyzing the spectroscopic data of 1, 2 and their O-acetyl derivatives (1a and 2a). Compounds 1 and 2 were epimers of each other at the C-9 position. The absolute configurations of 1 and 2 were assigned on the basis of NOESY data for 1, 2, 1a and 2a, a conformational analysis and the identity of the biogenetic pathway with verrucosidin (3). The planar structure of penicyrones was found in the SciFinder as a compound in the commercial chemical libraries; however, the stereostructure and spectroscopic data were not available. Therefore, this is the first study on the isolation and structure elucidation, including the absolute configurations, of penicyrones A (1) and B (2) as fungal metabolites. Compound 3 exhibited growth inhibitory activity against Mycobacterium smegmatis at 40 µg per disc (inhibition zone of 11 mm). This is the first study to demonstrate that verrucosidin (3) exhibited anti-mycobacterial activity.
Subject(s)
Gene Expression Regulation, Fungal/physiology , Penicillium/metabolism , Polyketides/chemistry , Polyketides/metabolism , Aquatic Organisms , Models, Molecular , Molecular Structure , Penicillium/geneticsSubject(s)
Antifungal Agents/chemistry , Antifungal Agents/isolation & purification , Mucor/drug effects , Penicillium/chemistry , Succinimides/chemistry , Succinimides/isolation & purification , Antifungal Agents/pharmacology , Environmental Microbiology , Humans , Japan , Magnetic Resonance Spectroscopy , Molecular Structure , Penicillium/isolation & purification , Succinimides/pharmacologyABSTRACT
Five new nucleoside antibiotics, named streptcytosines A-E (1-5), and six known compounds, de-amosaminyl-cytosamine (6), plicacetin (7), bamicetin (8), amicetin (9), collismycin B (10), and SF2738 C (11), were isolated from a culture broth of Streptomyces sp. TPU1236A collected in Okinawa, Japan. The structures of new compounds were elucidated on the basis of their spectroscopic data (HRFABMS, IR, UV, and 2D NMR experiments including 1H-1H COSY, HMQC, HMBC, and NOESY spectra). Streptcytosine A (1) belonged to the amicetin group antibiotics, and streptcytosines B-E (2-5) were derivatives of de-amosaminyl-cytosamine (6), 2,3,6-trideoxyglucopyranosyl cytosine. Compound 1 inhibited the growth of Mycobacterium smegmatis (MIC = 32 µg/mL), while compounds 2-5 were not active at 50 µg/disc. Bamicetin (8) and amicetin (9) showed the MICs of 16 and 8 µg/mL, respectively.
