Investigation of antiproliferative effect of Astragalus ponticus Pall. species and isolation of bioactive compounds

In this thesis study, two new chalcones (2,3',4'-trihydroxy-4-methoxychalcone (B5) and 2',5-dihydroxy-2,4'-dimethoxychalcone (B8)), two known chalcones (3-deoxysappanchalcone (B1) and isoliquiritigenin (B6)), two known isoflavanes (isomucronulatol (B10) and millepurpan (B15), one known aurone (2-(2,5-dihydroxybenzyl)-6-methoxyaurone (B3)), one known isoflavanquinone (pendulone (B2)), one known cycloartane glycoside (cyclogaleginoside B (B7)), and one steroid derivative (ergosterol peroxide (B14)) were isolated from Astragalus ponticus Pall. species by using bioactivity-guided fractionation. Also, from the non-active fractions, three known cycloartane-type compounds, namely astrasieversianin II (B11), astrasieversianin IV (B13) and astrasieversianin VI (B12), were isolated. Molecular structures of these isolated compounds were revealed by using spectroscopic methods like MS, 1D and 2D NMR and Single Crystal X-Ray Diffraction. Furthermore, these isolated compounds were tested in vitro for their antiproliferative activities against human cervical cancer cells (HeLa). B5, B7, B8 and B12 showed the highest activites with 36.6, 34.8, 20.6 ve 52.6 µM IC50 values, respectively. Whereas B3 and B14 showed no activity, the rest had IC50 values between 105.4-161.5 µM.