Design and synthesis of novel pyrrolo[2,3-a]carbazoles: 7-Chloro-2-oxo-3a-(2′-oxo-2′,3′-dihydro-1′H-indol-3′-yl)-2,3,3a,4,5,10-hexahydro-pyrrolo[3,2-a]carbazole-1-carbonitrile as an efficient anticancer agent

Abstract

Highly efficient poly functionalized pyrrolo[3,2-a]carbazoles via ring contraction through rearrangement and intramolecular Michael addition reaction using one pot multicomponent reaction (MCR) is reported for the first time. Free radical scavenging and anticancer activities were determined by DPPH and MTT assays respectively. Of these, compound 8d exhibited most potent activity against HCT-15 human colon cancer cell lines with an IC50 value of 9.9 μM and low toxicity toward normal human red blood cells. The morphological changes were visualized using scanning electron microscopy (SEM) technique, intracellular ROS generation measured by spectrofluorometer and gene expression levels of caspase-3, caspase-9 and Bcl-2 were determined using Semi quantitates PCR analysis for the target compound. Further, the structure activity relationships were also carried out. The results of the present study revealed that among pyrrolo[3,2-a]carbazole compounds, 7-chloro-2-oxo-3a-(2′-oxo-2′,3′-dihydro-1′H-indol-3′-yl)-2,3,3a,4,5,10-hexahydro-pyrrolo[3,2-a]carbazole-1-carbonitrile could be exploited as an excellent anticancer agent against colon cancer cells.