A new benzophenone, and the antiplasmodial activities of the constituents of Securidaca longipedunculata fresen (Polygalaceae)

• Published in: Natural product research 2022-06, Vol.36 (11), p.2758-2766
• Main Authors: Ochora, Douglas O., Kakudidi, Esezah, Namukobe, Jane, Heydenreich, Matthias, Coghi, Paolo, Yang, Li Jun, Mwakio, Edwin W., Andagalu, Ben, Roth, Amanda, Akala, Hoseah M., Wong, Vincent K. W., Yenesew, Abiy
• Format: Article
• Language: English
• Subjects: 2,3,4,5-tetramthoxybenzophenone; Antimalarials - pharmacology; Antiplasmodial; Antiprotozoal agents; Benzophenone; Benzophenones - pharmacology; Biocompatibility; Clinical isolates; Cytotoxicity; ex vivo; Hydroxybenzoate Ethers; Plant Extracts - pharmacology; Plasmodium falciparum; Polygalaceae; Securidaca; Securidaca longipedunculata; Toxicity
• ISSN: 1478-6419; 1478-6427
• DOI: 10.1080/14786419.2021.1925272

Extracts from Securidaca longipedunculata showed antiplasmodial activities against reference clones and clinical isolates using SYBR Green I method. A new benzophenone, 2,3,4,5-tetramethoxybenzophenone (1) was isolated and characterized along with seven known compounds: 4-hydroxy-2,3-dimethoxybenzophenone (2); 3-hydroxy-5-methoxybiphenyl (3), methyl-2-hydroxy-6-methoxybenzoate (4), benzyl-2-hydroxy-6-methoxybenzoate (5), 2-hydroxy-6-methoxybenzoic acid (6), 2,4,5-trimethoxybenzophenone (7) and 2-methoxy-3,4-methylenedioxybenzophenone (8). Compounds 1 and 2 showed ex vivo antiplasmodial activities (IC 50 28.8 μM and 18.6 μM, respectively); while 5 and 8 showed in vivo activities (IC 50 19.7 μM and 14.5 μM, respectively) against D6 strain. In a cytotoxicity assay, all the extracts (with an exception of the MeOH extract of the leaves) and pure compounds were not toxic to the normal LO2 and BEAS cell-lines, while the methanol roots extract (IC 50 66.4 µg/mL against A549, and 77.4 µg/mL against HepG2), compounds 6 (IC 50 22.2 µM against A549) and 7 (IC 50 45.2 µM against HepG2) were weakly active against cancerous cell-lines.