Dihydro-β-agarofuran sesquiterpenes and pentacyclic triterpenoids from the root bark of Osyris lanceolata

Three new dihydro-β-agarofuran polyesters, 1α,9β- difuranoyloxy-2-oxodihydro-β-agarofuran (1), 1α,9β- difuranoyloxy-2-oxo-3-enedihydro-β-agarofuran (2), and 1α,9β- difuranoyloxydihydro-β-agarofuran (3), have been isolated from the CHCl₃ extract of the root bark of Osyris lanceolata, together with two known pentacylic triterpenoids, 4 and 5. Compounds 1-5 did not scavenge the DPPH radical within 30 min of reaction time. All five compounds displayed antifungal activity against Candida albicans. Compounds 1, 3, 4, and 5 showed antibacterial activity against the Gram-positive Bacillus subtilis and Staphylococcus aureus and Gram-negative Escherichia coli and Pseudomonas aeruginosa, with 4 and 5 being the most active. Compound 2 displayed weak antibacterial activity only against Escherichia coli.