Human DNA topoisomerase inhibitors from Potentilla argentea and their cytotoxic effect against MCF-7

Two polyphenolics, kaempferol 3-O-beta-D-(6"-E-p-coumaroyl)-glucopyranoside (tiliroside) (1) and methyl brevifolincarboxylate (2) isolated from aerial parts of Potentilla argentea L. (Rosaceae) were evaluated for their cytotoxicities against human breast carcionoma cell line (MCF-7) and their DNA-binding ability. The DNA-binding ability of these compounds was studied by means of the human DNA topoisomerase I and II inhibition assay and ethidium displacement assay using calf thymus DNA, poly(dA-dT)2 and poly(dG-dC)2. Compound 2 was much more active and showed a higher level of cytotoxic potency than compound 1, with IC50 values of 1.11 +/- 2 microM and 21.60 +/- 2 microM, respectively. In DNA topoisomerase I and II inhibition in vitro assays both investigated compounds 1 and 2 were more effective against topoisomerase II than I. The results of DNA binding studies reveal that methyl brevifolincarboxylate had a greater DNA binding affinity that tiliroside, which correlates with its greater potency as a topoisomerase I/II inhibitor.

Flavonol glycosides from the flowers of Bellis perennis

Three flavonol glycosides, isorhamnetin 3-O-beta-D-galactopyranoside, isorhamnetin 3-O-beta-D-(6"-acetyl)-galactopyranoside and kaempferol 3-O-beta-D-glucopyranoside were isolated from the flowers of Bellis perennis.

Qualitative and quantitative chromatographic investigation of flavonoids in Bellis perennis L

The qualitative and quantitative analysis of flavonoids in the flowers and leaves of naturally growing B. perennis and in the flowers of cultivated variations 'rosea' and 'rubra' were carried out. The qualitative analysis was carried out by TLC and compared with flavonoid compounds isolated from flowers of common daisy. The quantitative determinations were carried out by Christ-Müller's method and by HPLC after acid hydrolysis. Similar flavonoids were found in all the flowers, while differences were noted in the flavonoid composition of the leaves. The flavonoid contents were higher in the flowers than in the leaves.

Apigenin glycosides from the flowers of Bellis perennis L

Two next apigenin glycosides, apigenin 7-O-beta-D-glucuronide [III], apigenin 7-O-beta-D-glucoside [IV] were isolated from the flowers of Bellis perennis L. Their structures were determined by means of chemical and spectroscopic methods.

Flavonoids, Phenolic Acids and Coumarins from the Roots of Althaea officinalis

From the roots of ALTHAEA OFFICINALIS two flavonoid glycosides were separated. Phenolic acids and coumarins were investigated chromatographically. The structures of the compounds were established on the basis of acid hydrolysis and spectroscopic methods (UV, (1)H-NMR, (13)C-NMR) as hypolaetin 8-glucoside and the new flavonoid sulphate - isoscutellarein 4'-methyl ether 8-glucoside-2''-SO (3)K.