Three new acridone alkaloids from Glycosmis lanceolata (Blume) D.Dietr. and their cytotoxic effects on tumour cell lines

We separated and structurally elucidated three new acridone alkaloids (glycomontamine A (1), B (2), and C (3)), together with three known compounds (glycofoline, kokusaginine and dictamnine) from the acetone extract of Glycosmis lanceolata (Blume) D.Dietr. branches collected in Thailand. The compounds were assayed for cell viability using human lung adenocarcinoma cell line A549, breast adenocarcinoma cell line T47D, cervix epithelioid carcinoma cell line Hela, acute lymphoid leukaemia B cell line NALM-6, and human dermal fibroblasts. The viability of Hela cells treated with compound 1 (IC50 17.6 mu M) and T47D cells treated with compound 2 (IC50 17.4 mu M) decreased dose-dependently. Both compounds also showed cytotoxicity against NALM-6 cells (IC50 16.5 and 9.3 mu M). Additionally, compound 1 decreased the mitochondrial membrane potential of Hela cells, whereas compound 2 did not change the mitochondrial membrane potential in T47D cells. [GRAPHICS]