β-Cyclodextrin catalyzed one-pot four component auspicious protocol for synthesis of spiro[acridine-9,3′-indole]-2′,4,4′(1′H,5′H,10H)-trione as a potential antimicrobial agent

ABSTRACT

We have developed an perceptive and facile approach for the synthesis of new spiro[acridine-9,3′-indole]-2′,4,4′(1′H,5′H,10H)-trione derivatives (4a–t) by one-pot four component condensation involving two equivalence of dimedone (1), substituted anilines (2a–t), and isatin (3) catalyzed by β-cyclodextrin in water within short reaction time at 80 °C in good to excellent yields. We believe that this novel procedure may open the door for the easy generation of new and bioactive spiro[acridine-9,3′-indole]-2′,4,4′(1′H,5′H,10H)-triones. The most exciting feature of this methodology is its mechanism involving the unusual ring opening of an isatin moiety followed by recyclization. Synthesized compounds were evaluated for their antimicrobial activities against four bacteria and three fungi. All the spirooxindole derivatives exhibited significant antibacterial activity against bacteria and fungi. Among 20 compounds screened, compound (4i) and (4h) was found to be more active against tested bacterial strain.

GRAPHICAL ABSTRACT

KEYWORDS:

• Antimicrobial activity
• β-cyclodextrin
• multicomponent reaction
• spiro[acridine-9,3′-indole]-2′,4,4′(1′H,5′H,10H)-trione
• supramolecular catalyst

Acknowledgments

This work was supported by Special Assistance Programme SAP, University Grants Commission, New Delhi, India, intended to encourage the pursuit of excellence and teamwork in advanced teaching and research to accelerate the realization of international standards in specific fields.