Nine undescribed caged polycyclic polyprenylated acylphloroglucinols (PPAPs), including adamantane type PPAPs ( 1–2 ), and homoadamantane type PPAPs ( 3–9 ), were isolated from the fruits of Garcinia multiflora , along with three known analogues. A new epimeric pair of isohypersampsonone B ( 5 ) and epi-isohypersampsonone B ( 6 ), featuring an unusual hexahydrofuro[2,3-b]furan-diepoxy ring system fused in a homoadamantane skeleton, was not separated due to the rapid equilibration between the two isomeric forms. All new caged PPAPs ( 1–9 ), sharing a common isogeranyl group, were determined on the basis of comprehensive NMR and MS spectroscopic data. Their cytotoxicity against three human tumor cell lines (SGC-7901, HepG2, HCT-116) and the nitric oxide production inhibitory activity of lipopolysaccharides-stimulated RAW 264.7 cells were tested. Compounds 8 and 12 displayed mild cytotoxicity against three human cancer cell lines with IC _(50) values of 10–20 μM. Furthermore, compounds 8 and 12 also exhibited NO production inhibitory effect with an IC _(50) value of 18.24 and 12.50 μM respectively.
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