Polyhydroxy cucurbitane triterpenes from Hemsleya penxianensis tubers

Ten new cucurbitane triterpenoids, hemsleyacins A-J (1-10), together with three known cucurbitane triterpenoids, dihydrocucurbitacin F (11), scandenogenin D (12), and jinfushanencin F (13), were separated from ethanolic tuber extracts of Hemsleya penxianensis. The absolute configurations of the new compounds were established based on NMR, HRESIMS, and CD spectra. Compounds 7 and 10-12 were evaluated in terms of their antifeedant activity against Plutella xylostella larvae. The result showed that compound 10 exhibited potent antifeedant activity against P. xylostella larvae after 48 h of treatment. Furthermore, the MTT test showed that compound 11 exhibited potent inhibition toward the UMUC-3 and T24 cell lines with IC₅₀ values of 29.12 and 35.62 μM, respectively, compared to the positive control cisplatin IC₅₀ values of 8.27 and 13.72 μM. Western blot analysis revealed that compound 11 treatments substantially inhibited the phosphorylation of IκBα.