Synthesis, spectral characterization and bioactivity evaluation of novel α-aminophosphonates

GRAPHICAL ABSTRACT

ABSTRACT

A facile synthesis of novel α-aminophosphonates 5a-j was accomplished by condensation of imines (3a-j) with diethyl phosphite (4) in ethanol at 50–60°C using easily recoverable and reusable catalyst, tetramethyl guanidine (TMG) via pudovik reaction in high yields. All the title compounds were characterized by spectral and elemental analysis. They were further screened for their abilities towards in vitro antibacterial, antifungal and antioxidant activities. The compounds 5g, 5d, 5f exhibited good antibacterial and antifungal activities compared to the standard bactericide, Penicillin and fungicide, Griseofulvin, respectively. The compounds 5h, 5i, 5g, and 5c exhibited good antioxidant activity compared to the standard ascorbic acid.

KEYWORDS:

• α-Aminophosphonate
• 6-amino-indazole
• diethylphosphite
• Pudovik reaction
• antibacterial
• antifungal and antioxidant activities

Acknowledgments

The authors G. Madhava and S. K. Thaslim Basha acknowledge the University Grants Commission for the award of Senior Research Fellow (SRF). Also, the authors express their thanks to Hyderabad Central University for providing instrumentation facilities for recording the spectra.