Dihydroxylated 2,6-diphenyl-4-chlorophenylpyridines: Topoisomerase I and IIα dual inhibitors with DNA non-intercalative catalytic activity

다국어 초록 (Multilingual Abstract)

<P><B>Abstract</B></P> <P>With the aim to develop novel antiproliferative agents, a new series of eighteen dihydroxylated 2,6-diphenyl-4-chlorophenylpyridines were systematically designed, prepared, and investigated for their topoisomerase (topo) I and IIα inhibitory properties and antiproliferative effect in three different human cancer cell lines (HCT15, T47D, and HeLa). Compounds <B>22–30</B> which possess a <I>meta</I>- or <I>para</I>-phenol on 2-, or 6-position of central pyridine ring showed significant dual topo I and topo IIα inhibitory activities with strong antiproliferative activities against all the tested human cancer cell lines. However, compounds <B>13</B>–<B>21</B> which possess an <I>ortho</I>-phenol on 2-, or 6-position of central pyridine ring did not show significant topo I and topo IIα inhibitory activities but displayed moderate antiproliferative activities against all the tested human cancer cell lines. Compound <B>23</B> exhibited the highest antiproliferative potency as much as 348.5 and 105 times compared to etoposide and camptothecin, respectively, in T47D cancer cell line. The structure-activity relationship study revealed that the <I>para</I> position of a hydroxyl group at 2-and 6-phenyl ring and chlorine atom at the <I>para</I> position of 4-phenyl ring of the central pyridine exhibited the most significant topo I and topo IIα inhibition, which might indicate introduction of the chlorine atom at the phenyl ring of 4-pyridine have an important role as dual inhibitors of topo I and topo IIα. Compound <B>30</B> which showed the most potent dual topo I and topo IIα inhibition with strong antiproliferative activity in T47D cell line was selected to perform further study on the mechanism of action, which revealed that compound <B>30</B> functions as a potent DNA non-intercalative catalytic topo I and IIα dual inhibitor.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Dihydroxylated 2,6-diphenyl-4-chlorophenylpyridines were designed and synthesized. </LI> <LI> Introduction of chlorine on 4-phenyl ring of central pyridine showed strong dual topo I and IIα inhibitor. </LI> <LI> Compound <B>30</B> exhibited the most potent dual topo I and IIα inhibition with strong antiproliferative activity. </LI> <LI> Compound <B>30</B> acts as a DNA non-intercalative catalytic topo IIα inhibitor. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>