Bioactivity-guided fractionation of hexane and dichloromethane extracts of the bark of Casearia grewiifolia afforded four new clerodane diterpenes, caseargrewiins A-D (1-4), and two known clerodane diterpenes, rel-(2S,5R,6R,8S,9S,10R,18S,19R)-18,19-diacetoxy-18,19-epoxy-6-methoxy-2-(2-methylbutanoyloxy)cleroda-3,13(16),14-triene (5) and rel-(2S,5R,6R,8S,9S,10R,18S,19R)-18,19-diacetoxy-18,19-epoxy-6-hydroxy-2-(2-methylbutanoyloxy)cleroda-3,13(16),14-triene (6). The structures of 1-4 were established on the basis of the interpretation of their 1D and 2D NMR spectral data. The absolute configuration of 4 was determined by the modified Mosher's method. All compounds exhibited promising antimalarial and antimycobacterial activities but also cytotoxicity against three cancer cell lines.

Investigation of the fungus Chaetomium globosum KMITL-N0802 led to the isolation of a novel anthraquinone-chromanone compound named chaetomanone along with seven known compounds, ergosterol, ergosteryl palmitate, chrysophanol, chaetoglobosin C, alternariol monomethyl ether, echinuline and isochaetoglobosin D. These compounds were characterized by spectroscopic methods. Chaetomanone and echinulin exhibited activity towards Mycobacterium tuberculosis.

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Three new azaphilones named rotiorinols A-C (1-3), two new stereoisomers, (-)-rotiorin (4) and epi-isochromophilone II (5), and a known compound, rubrorotiorin (6), were isolated from the fungus Chaetomium cupreum CC3003. Structures were established on the basis of spectroscopic evidence. The absolute configuration of 1 was determined by the modified Mosher's method along with an X-ray analysis of its acetate derivative, as well as by chemical transformation. Compounds 1, 3, 4, and 6 exhibited antifungal activity against Candida albicans with IC50 values of 10.5, 16.7, 24.3, and 0.6 microg/mL, respectively.