Enantioselective approach towards the synthesis of spiro-indeno [1,2-b] quinoxaline pyrrolothiazoles as antioxidant and antiproliferative

The 1,3-dipolar cycloaddition reactions of azomethine ylide generated in situ from indeno quinoxaline and thiazolidine-2-carboxylic acid to a series of quinoline bearing dipolarophile afforded novel spiro indeno-quinoxaline pyrrolo thiazoles in quantitative yields. The newly synthesized compounds were characterized using different spectroscopic techniques. Furthermore, the molecular structure of compound 5c was confirmed by single crystal X-ray crystallography. The synthesized compounds were screened for their in vitro antioxidant activity and in vitro cytotoxic activity against breast cancer cell line MCF-7 and adenocarcinomic cancer cell line A-549. Compound containing more electron donors in quinoline site were found to be more potent with good IC50 values. (C) 2018 Elsevier Ltd. All rights reserved.