Identification and bioactivity evaluation of twelve previously undescribed depsidone derivatives from Garcinia...

Phytochemical studies on the leaves and twigs of Garcinia oligantha Merr. led to the isolation of twelve previously undescribed depsidone derivatives (oliganthdepsidones A-L, 1-12). Their structures were elucidated by extensive spectroscopic analysis including ¹H and ¹³C NMR, HSQC, HMBC and NOESY along with HRESIMS. The structures of oliganthdepsidones G and J were finally determined using DFT-NMR chemical shift calculations and DP4+ methods. Cytotoxicity test in four human cancer cell lines indicated that oliganthdepsidone F had relatively strong cytotoxic effect against A375 (melanoma), A549 (lung cancer), HepG2 (liver cancer), and MCF-7 (breast cancer) cell lines with IC₅₀ of 18.71, 15.44, 10.92, and 15.90 μM, respectively. The dose- and time-dependent antiproliferative effects of oliganthdepsidone F on these cell lines were also observed by CCK-8 test. As determined by fluorescent microscopy and flow cytometry in these cell lines, oliganthdepsidone F could promote cell apoptosis, leading to the inhibition of cell proliferation. The results of wound healing assay and transwell assay showed that oliganthdepsidone F could inhibit the migration and invasion of A549 and MCF-7 cell lines in a concentration-dependent manner.