Abstract
Present study involves the synthesis of bis-coumarins and novel polycyclic pyranodichromenones
using a catalyst-free approach under ultrasonic irradiation in an aqueous medium.
The chemical structures of the synthesized compounds were characterized using FTIR,
1 H NMR, and 13 C NMR spectroscopy. The antibacterial and antifungal activities of the compounds were
evaluated against Gram-positive (S. aureus , B. cereus ) and Gram-negative bacteria (P. aeruginosa , E. coli ), as well as the fungus C. albicans , using the disc diffusion method. Several compounds exhibited excellent activity
against the tested microorganisms. Moreover, the antioxidant potential of the synthesized
products was assessed using 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic
acid) (ABTS) free radical scavenging, and total antioxidant capacity (TAC) assays.
Promising antioxidant activity was observed for certain compounds. Computational studies
using density functional theory (DFT) were conducted to investigate the molecular
reactivity and electronic properties of the synthesized compounds. Quantum mechanical
parameters such as Ionization Potential (IP), Electron Affinity (EA), Mulliken Electronegativity
(χ), Chemical Potential (μ), and Electrophilicity Index (ω) were calculated. The study
highlights the efficiency and eco-friendliness of ultrasonic-assisted processes, contributing
to the advancement of sustainable chemistry.
Key words biscoumarins - polycyclic pyranodichromenones - one pot synthesis - antioxidant activity
- antibacterial activity - antifungal activity - DFT
