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A novel tetracyclic polyketide uniquely spiro-attached with a γ-lactone ring and a potent cytotoxic agent possessing a thiol-reactive pharmacophore were isolated from the mangrove endophytic fungus Penicillium chermesinum.

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New protoberberine alkaloids, namely alangiumkaloids A (1) and B (2), 27-O-trans-caffeoylcylicodiscic acid (3), and β-Dglucopyranos-1-yl N-methylpyrrole-2-carboxylate (5) together with myriceric acid B (4), isoalangiside (6), alangiside (7), 3-O-demethyl-2-O-methylalangiside (8), and demethylalangiside (9) have been isolated from Alangium salviifolium. The cancer chemopreventive properties and cytotoxic activities of the isolated compounds were evaluated. Compounds 3, 4, and 9 scavenged DPPH free radicals with IC 50 values of 21.4, 21.8, and 24.0 μM, respectively. Alangisides 7 and 9 inhibited superoxide anion radical formation in the xanthine/

Five metabolites, ( Z)-6-benzylidene-3-hydroxymethyl-1,4-dimethyl-3-methylsulfanylpiperazine-2,5-dione ( 1), (3S,3'R)-3-(3'-hydroxybutyl)-7-methoxyphthalide ( 2), ( S)-3-butyl-7-methoxyphthalide ( 3), (3R,6R)-bisdethiodi(methylthio)hyalodendrin ( 4), and bis- N-norgliovictin ( 5), were isolated from the culture broth of the marine derived fungus of the order Pleosporales strain CRIF2. Compounds 1 and 2 are new fungal metabolites, while 3 was isolated for the first time as a natural product. Compounds 1, 3, and 4 exhibited only weak cytotoxic activity, while 5 was inactive at 50 microg/mL.

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Seven known mammea coumarins, mammea A/AA cyclo D ( 1 ), mammea A/AD cyclo D ( 2 ), mammea A/AB cyclo D ( 3 ), mammea A/AC cyclo F ( 4 ), mam-mea A/AB cyclo F ( 5 ), mammea A/AA cyclo F ( 6 ), mammea B/AC cyclo F ( 7 ), were isolated for the first time from the hexane extract of Mammea siamensis . A detailed analysis of both 1D and 2D NMR spectral data of these compounds was made.