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Pesimquinolones produced by Penicillium simplicissimum and their inhibitory activity on nitric oxide production
Chong Dai1, Chunmei Chen1, Danyingzi Guan1
1Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
Abstract:
Eight undescribed quinolone alkaloids, pesimquinolones A-H, as well as six known compounds, were isolated from the solid culture broth of the fungus Penicillium simplicissimum. Their chemical structures were characterized by combined analyses of NMR spectroscopy and single-crystal X-ray crystallography. Pesimquinolones A-G are the first examples of naturally occurring quinolone alkaloids possessing a limonene moiety. Their anti-inflammatory activities on LPS-induced nitric oxide (NO) production in adherent cells were evaluated. Pesimquinolones A, E, G, and H showed promising suppressive effect on the production of NO with IC50 values of 1.94, 1.29, 1.20, and 1.23 μM, respectively.
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