Synthesis and anti-tyrosine kinase activity of 3-(substituted-benzylidene)-1, 3-dihydro-indolin derivatives: investigation of their role against p60c-Src receptor tyrosine kinase with the application of receptor docking studies

A series of 3-(substituted-benzylidene)-1, 3-dihydro-indolin-2-thione derivatives were synthesized as modified congeners of 3-(substituted-benzylidene)-1, 3-dihydro-indolin-2-one series. All the synthesized compounds were examined for their in vitro anti-tyrosine kinase activity against p60^c-Src. The activity results revealed that compounds (Z)-3-(4′-Dimethylamino-benzylidene)-1, 3-dihydro-indolin-2-thione (12) (E)-3-(2′, 6′-Dichloro-benzylidene)-1, 3-dihydro-indolin-2-thione (13) and (E)-3-(3′-Hydroxy-4′-methoxy-benzylidene)-1, 3-dihydro-indolin-2-thione (19) exhibited anti-tyrosine kinase activity with IC₅₀ value of 21.91, 21.20 and 30.92 μM, respectively. These results are comparable to PP1 [1-tert-Butyl-3-p-tolyl-1H-pyrazolo[3, 4-d]pyrimidine-4-yl-amine] (IC₅₀ = 0.17 μM), which is reported as a potent and selective p60^c-Src tyrosine kinase inhibitor. Some thio congeners are found to be more potent than oxo derivatives; however, no significant correlation was observed between the activity profiles of these two series. Docking program was used to investigate the docking mode of each compound at the active site. Among all of the compounds, only (Z)-3-(2′-Chloro-benzylidene)-1, 3-dihydro-indolin-2-one (8) and (E)-3-(3′-Nitro-benzylidene)-1, 3-dihydro-indolin-2-thione (16) were docked at the active site where the PP1 was embedded.