Yb/Chitosan Catalyzed Synthesis of Highly Substituted Piperidine Derivatives for Potential Nuclease Activity and DNA Binding Study

Background: Herein, a new chitosan-supported ytterbium nano-catalyst has been prepared and used in a mild, efficient, and expeditious method for the synthesis of substituted piperidine derivatives via threecomponent condensation of substituted anilines, formaldehyde and different cyclic/acyclic active methylene compounds at room temperature. Methods: The catalyst was characterized by FTIR, XRD, SEM, EDX, TEM, ICP-AES and the stability of the catalyst was evaluated by TG analysis. The synthesized compound 3,3,11,11-Tetramethyl-15-(phenyl)-15- azadispiro[5.1.5.3]hexadecane-1,5,9,13-tetrone (3a) was explored for pBR322 DNA cleavage activity and genotoxicity. Further, the interaction of 3a with CT-DNA was investigated through UV-vis, fluorescence and viscosity. Results: The preparation of Yb/chitosan nano-catalyst was verified and the catalyst was found effective towards substituted piperidine formations with the catalyst reusability. Compound 3a was successfully tested for DNA cleavage activity. In addition, fluorescence results revealed that compound 3a interacted with DNA with a binding affinity of 4.84 x 10⁴ M^-1. Conclusion: Our findings suggest that compounds bearing spiro-piperidine scaffold, synthesized using reusable nano-catalyst, could be effective biological agents