One-Step Synthesis of 3,4-Diphenyl-2-pyrrolinones by Solvent-Free and Bi2O3-Catalyzed Approaches and Cytotoxicity Screening Against Glioma Cells

Article abstract of DOI:10.1002/jhet.2921

Multifunctionalized 2-pyrrolinones were synthesized from the formal aza-[3?+?2] cycloaddition reaction of acyclic enaminones and diphenylcyclopropenone. For primary enaminones, solventless reaction under microwave heating was developed. On the other hand, catalysis by Bi₂O₃ under conventional heating was the more suitable strategy when secondary enaminones were employed. These conditions allowed the synthesis of a set of 2-pyrrolinones with two vicinal phenyl substituents, which were evaluated for cytotoxicity against U251 and C6 glioblastoma cells. In general, all tested 2-pyrrolinones with two vicinal phenyl rings were more active than those without this structural moiety, and 1-butyl-5-methyl-5-(2-oxopropyl)-3,4-diphenyl-1,5-dihydro-2H-pyrrol-2-one was the most cytotoxic and appears to be a new possibility as an antitumor scaffold to this aggressive brain tumor.