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The Journal of Antibiotics (2016) 69, 5761& 2016 Japan Antibiotics Research Association All rights reserved 0021-8820/16 http://www.nature.com/ja
Web End =www.nature.com/ja
Ying-Yue Bu, Hiroyuki Yamazaki, Ohgi Takahashi, Ryota Kirikoshi, Kazuyo Ukai and Michio Namikoshi
Two polyketides containing an -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 congurations 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 rst study on the isolation and structure elucidation, including the absolute congurations, of penicyrones A (1) and B (2) as fungal metabolites. Compound 3 exhibited growth inhibitory activity against Mycobacterium smegmatis at 40 g per disc (inhibition zone of 11 mm). This is the rst study to demonstrate that verrucosidin (3) exhibited anti-mycobacterial activity.
The Journal of Antibiotics (2016) 69, 5761; doi:http://dx.doi.org/10.1038/ja.2015.82
Web End =10.1038/ja.2015.82; published online 5 August 2015
INTRODUCTION
Marine natural resources have continued to provide structurally and biologically novel compounds, some of which are promising leads for the development of new drugs.13 Marine microorganisms, especially marine-derived fungi, have been attractive and important sources of pharmacologically active secondary metabolites.46 Marine fungal metabolites, possessing unique structures and biological properties, are expected to become candidates for advanced medicines and biochemical reagents.46
In the course of our search for useful bioactive substances from marine microorganisms, the marine-derived Penicillium sp. TPU1271 was found to produce various types of secondary metabolites.HPLC separation from a culture broth of strain TPU1271 led to the isolation of an epimeric pair of polyketides containing -pyrone and the tetrahydrofuran rings, penicyrones A (1) and B (2) (Figure 1), as...