Antibacterial and Antiplasmodial Constituents of <i>Beilschmiedia cryptocaryoides</i>

Four new beilschmiedic acid derivatives, cryptobeilic acids A–D (<b>1</b>–<b>4</b>), and tsangibeilin B (<b>5</b>) have been isolated from the bark of <i>Beilschmiedia cryptocaryoides</i> collected from Madagascar. Their structures were elucidated using detailed spectroscopic and spectrometric methods. Cryptobeilic acid A (<b>1</b>) and tsangibeilin B (<b>5</b>) structures were confirmed by single-crystal X-ray diffraction analysis. Compounds <b>1</b>–<b>5</b> displayed moderate antibacterial activity against <i>Escherichia coli</i> 6r3, <i>Acinetobacter calcoaceticus</i> DSM 586, and <i>Pseudonamas stutzeri</i> 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 <i>Plasmodium falciparum</i> strain NF54 and weak cytotoxicity against L6 cell lines

Antibacterial and Antioxidant Xanthones and Benzophenone from Garcinia smeathmannii

Fouotsa H, Lannang AM, Dzoyem JP, et al. Antibacterial and Antioxidant Xanthones and Benzophenone from Garcinia smeathmannii. Planta Medica. 2015;81(7):594-599.A new prenylated xanthone, 1,3,5,8-tetrahydroxy-2-(3-methybut-2-enyl)-4-(3,7-dimethylocta-2,6-dienyl) xanthone (1), and a new benzophenone (2), together with four known xanthone derivatives, cheffouxanthone (3), smeathxanthone A (4), smeathxanthone B (5), ananixanthone (6), and two pentacyclic triterpenes, epi-friedelinol (7) and friedelin (8), were isolated from the stem bark of Garcinia smeathmannii. The structures of the compounds were elucidated on the basis of 1D and 2DNMR experiments, and compound 2 was further characterized and confirmed by single X-ray analysis. Compounds 1, 2, and 3 exhibited the most prominent antibacterial activity against gram-positive Enterococcus faecalis with minimal inhibitory concentration values of 8, 8, and 2 mu g/mL, respectively, while compounds 1, 3, 4, and 6 showed the capacity to scavenge free radicals

Long-chain alkyl-substituted gentisic acid and benzoquinone derivatives from the root of Micronychia tsiramiramy (Anacardiaceae)

Razakarivony AA, Lenta Ndjakou B, Andriamihaja B, et al. Long-chain alkyl-substituted gentisic acid and benzoquinone derivatives from the root of Micronychia tsiramiramy (Anacardiaceae). Zeitschrift für Naturforschung B. 2016;71(4):297-303.A new gentisic acid derivative named micronyc acid (1) and a new 1,4-benzoquinone derivative named micronone (2) have been isolated from the root of Micronychia tsiramiramy together with the known compounds gallic acid (3), methyl gallate (4), moronic acid (5), masticadienolic acid (6), and masticadienediol (7). The structures of 1 and 2 were established using MS and NMR. Compound 1 was tested for antiplasmodial activity in vitro against the chloroquine-resistant strain Plasmodium falciparum W2 and displayed moderate antiplasmodial activity in vitro with an IC50 value of 25.6 mu m. Compounds 1 and its acetyl derivative 1a were also tested for their cytotoxicity against the human cervix carcinoma cell line KB-3-1 and still showed moderate activity