A new steroidal glycoside from the fruits of Solanum myriacanthum.

A new cholestane-type steroidal glycoside, solamyriaside A (1), was isolated from the fruits of Solanum myriacanthum Dunal (Solanaceae), along with two known steroidal glycosides, namely, solaviaside A (2) and aculeatiside A (3), and three known steroidal alkaloid glycosides, namely, solamargine (4), khasianine (5) and solasonine (6), which were isolated for the first time from this plant. Based on spectroscopic data as well as chemical evidence, 1 was determined to be 3-O-α-L-rhamnopyranosyl-(1→2)-O-[α-L-rhamnopyranosyl-(1→4)]-ß-D-glucopyranosyl-22R,25R-cholest-5-ene-3ß,16α,22,26-tetraol 26-O-ß-D-glucopyranoside. The cytotoxic activity of 1-6 against HL-60 human promyelocytic leukaemia cells was examined. Compounds 4-6 showed cytotoxic activity. Among them, 4 exhibited the strongest activity with an IC50 value of 4.64 ± 0.17 µM, similar to the activity of cisplatin, a positive control.

Two new triterpenoids from the leaves and stems of Lantana camara.

Two new oleanane-type triterpenoids with an epoxy bridge between C-3 and C-25, named lantacamaric acids A and B, were isolated from the leaves and stems of Lantana camara L. (Verbenaceae). In addition, seven known triterpenoids, two known iridoid glycosides, four known phenylethanoid glycosides, one known flavonoid glycoside, and one known cyanogenic glycoside were isolated. Their structures were determined based on the spectroscopic data. Furthermore, the cytotoxic activities of the isolated triterpenoids toward HL-60 cells were examined. The IC50 values of all compounds were obtained and ranged from 1.16 to 68.4 µM, with three compounds exhibiting stronger activities than the positive control, cisplatin. In addition, the structure-activity relationship was investigated.