In the search for new compounds to protect plants from fungi, an endophytic fungus, Epicoccum sp. CAFTBO, obtained from Theobroma cacao was found to produce three polyoxygenated polyketides, namely epicolactone (1) and epicoccolides A (2) and B (3), together with seven known metabolites. The structures of these compounds were elucidated by a combination of detailed spectroscopic and spectrometric analyses as well as DFT calculations of the electronic circular dichroism spectra and the single‐crystal X‐ray diffraction analysis of 1. Compounds 1–3 showed potent antimicrobial activities and significant inhibitory effects on the mycelial growth of two peronosporomycete phytopathogens, Pythium ultimum and Aphanomyces cochlioides, and the basidiomycetous fungus Rhizoctonia solani.

Eight new triterpenoids, prototiamins A-G (1-6, 9) and seco-tiaminic acid A (10), were isolated along with four known compounds from the bark of Entandrophragma congoënse. Their structures were elucidated by means of HRMS and different NMR techniques and chemical transformations. Assignments of relative and absolute configurations for the new compounds were achieved using NOESY experiments and by chemical modification including the advanced Mosher's method. Additionally, the structure and relative configuration of compound 3 were confirmed by single-crystal X-ray diffraction analysis. Compounds 1, 3, and 5 displayed significant in vitro antiplasmodial activity against the erythrocytic stages of chloroquine-sensitive Plasmodium falciparum strain NF54. Prototiamin C (3) was the most potent of the compounds isolated, with an IC50 value of 0.44 μM. All compounds tested showed low cytotoxicity for the L6 rat skeletal myoblast cell line.

Four new beilschmiedic acid derivatives, cryptobeilic acids A-D (1-4), and tsangibeilin B (5) have been isolated from the bark of Beilschmiedia cryptocaryoides collected from Madagascar. Their structures were elucidated using detailed spectroscopic and spectrometric methods. Cryptobeilic acid A (1) and tsangibeilin B (5) structures were confirmed by single-crystal X-ray diffraction analysis. Compounds 1-5 displayed moderate antibacterial activity against Escherichia coli 6r3, Acinetobacter calcoaceticus DSM 586, and Pseudonamas stutzeri A1501, with the minimum inhibitory concentrations ranging from 10 to 50 μM, respectively. In addition, the compounds exhibited antiplasmodial activity against erythrocytic stages of chloroquine-resistant Plasmodium falciparum strain NF54 and weak cytotoxicity against L6 cell lines.

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