Synthesis, characterization and antimicrobial properties of two derivatives of pyrrolidine-2,5-dione fused at positions-3,4 to a dibenzobarrelene backbone

A new diazo derivative of a pyrrolidine-2,5-dione (8) fused at position-3,4 to a dibenzobarrelene backbone has been prepared by coupling the previously reported N-arylsuccinimid (5) precursor with aryldiazonium ion of aniline. The initial step of the reaction involved the preparation of the intermediate 9,10-dihydro-9,10-ethanoanthracene-11,12-dicarboxylic anhydride (3) through [4 + 2]-cycloaddition between anthracene and maleic anhydride in refluxing xylene which was then condensed with para-aminophenol to give compound 5. Compounds 5 and 8 were characterized by their physical, elemental, and spectroscopic data. 2D-NMR (COSY, HSQC, and HMBC) techniques were used to confirm the structure of compound 5. Compounds 5 (MIC = 32-128 μg/mL) and 8 (MIC = 16-256 μg/mL) along with the precursor 3 (MIC = 64-128 μg/mL) displayed moderate to low antimicrobial activities against selected bacterial and fungal species when compared with those of nystatin (MIC = 0.50-2 μg/mL) and ciprofloxacin (MIC = 0.50-16 μg/mL) used as reference drugs.