Three new flavonol glycosides, fissflavosides A-C (1–3), together with six known flavonol glycosides, kaempferol 3-O-α-L-rhamnopyranosyl-(1→2)-β-D-galactopyranoside (4), kaempferol 3-O-α-L-rham-nopyranosyl-(1→6)-β-D-galactopyranoside (5), kaempferol 3-O-α-L-rhamnopyranosyl-(1→6)-β-D-glucopyranoside (6), rhamnetin 3-O-α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranoside (7), rutin (8), and isorhamnetin 3-O-α-L-rhamnopyranosyl-(1→2)-β-D-galactopyranoside (9) were isolated from the methanol extract of the Fissistigma pallens leaves. Their chemical structures were determined by 1D-, 2D-NMR, and MS data as well as in comparison with reported data in the literature. Compounds 1–9 showed weak cytotoxic activity on three human cancer cell lines, HT-29, A-2058, A-549 with IC50 ranging from 134.6 to 162.6 µM. In addition, the antioxidant capacities of compounds were also tested by ORAC assay. All compounds showed significant antioxidant with trolox equivalents ranging from 4.4 to 8.6 µM at the concentration of 1.0 µM. The results indicated 7 and 8 having meaningful reducing capacity of copper (I) ions of 2.7 to 6.9 µM at the concentrations of 1 and 2 µM.
Bibliographical noteFunding Information:
This research is funded by Vietnam National Foundation for Science and Technology Development (NAFOSTED) under grant number 104.01-2015.79 and by National Research Foundation of (NRF) grant [NRF-2016R1A2B4006742] funded by the Ministry of Education, Science and Technology, Republic of Korea; NAFOSTED [104.01-2015.44]; NRF [2016R1A2B4006742].
All Science Journal Classification (ASJC) codes
- Analytical Chemistry
- Applied Microbiology and Biotechnology
- Molecular Biology
- Organic Chemistry