Tomentosones A and B, Hexacyclic Phloroglucinol Derivatives from the Thai Shrub Rhodomyrtus tomentosa
journal contributionposted on 06.01.2012, 00:00 by Asadhawut Hiranrat, Wilawan Mahabusarakam, Anthony R. Carroll, Sandra Duffy, Vicky M. Avery
Two phloroglucinols named tomentosones A and B (1 and 2) that each possess a novel hexacyclic ring system were isolated from the CH2Cl2 extract of Rhodomyrtus tomentosa leaves. Their structures were elucidated from analyses of 2D NMR spectroscopic data. Tomentosone A inhibited the growth of chloroquine-resistant and -sensitive strains of the malaria parasite Plasmodium falciparum, with IC50 values of 1.49 μM and 1.0 μM, respectively, while tomentosone B was significantly less active.