Synthesis and Biological Evaluation of 3-Alkyl-1,5-Diaryl-1<i>H - Fig 8 </i>-Pyrazoles as Rigid Analogues of Combretastatin A-4 with Potent Antiproliferative Activity

<p>(A) tubulin is displayed as a flat ribbon with <i>α</i>-tubulin coloured lavender and <i>β</i>-tubulin coloured cyan. Superimposition of the presumptive conformation of active <b>7k</b> (pink model) with that of <b>1</b> (green model). The structures were docked into the colchicine binding site of tubulin (PDB ID: 1SA0). (B) the amino acids of tubulin within 5.0 Å of colchicine are shown as lines models. Hydrogen bonds (distance: <3.5 Å) are shown as dotted line.