Synthesis, crystal structure, cytotoxicity and evaluation of the 6-oxo-6H-pyrrolo[3,2,1-ij]quinoline-5-carbaldehydes for inhibitory effect against protein kinases (VEGFR-2 and EGFR) and cyclooxygenase-2 (COX-2) activities

Abstract The 2-aryl-8-bromo-6-oxo-6H-pyrrolo[3,2,1-ij]quinoline-5-carbaldehydes 2a–e were prepared and their structure characterised using a combination of NMR (1H- & 13C-), infrared and mass spectroscopic techniques. Their structure and geometry were also confirmed in the solid state by means of single crystal X-ray diffraction method. The compounds were evaluated for cytotoxicity in vitro against the human MCF-7 and MDA-MB-231 breast cancer cell lines as well for toxicity against the human embryonic kidney derived Hek293-T cell line. Preliminary apoptotic assay using DNA laddering assay revealed that these compounds have potential to induce apoptosis in the MCF-7 cell line. Compounds 2c and 2d were also found to exhibit increased inhibitory activity against vascular endothelial growth factor receptor-2 (VEGFR-2) tyrosine kinase and significant interruption of cyclooxygenase-2 (COX-2) activity.