Phosphorus, Sulfur and Silicon and the Related Elements, 2025 (SCI-Expanded, Scopus)
A green and efficient approach was developed for the synthesis of twenty-three α-aminophosphonate derivatives (4a-4v) via the Kabachnik–Fields reaction, using acetylsalicylic acid as a novel eco-friendly Brønsted acid catalyst under ultrasound irradiation and solvent-free conditions. The target compounds were obtained in moderate to excellent yields (43 - 91%) and were structurally characterized by FTIR, 1H NMR, 13C NMR, and single-crystal X-ray diffraction analysis. Notably, the crystal structure of compound 4c was elucidated by X-ray diffraction, providing detailed molecular and supramolecular insights. The antioxidant activity of the synthesized compounds was evaluated through four in vitro assays (DPPH, ABTS, FRAP, and phenanthroline), with compounds 4a, 4c, 4d, and 4k demonstrating significant potency. Additionally, antifungal activity was assessed against Fusarium oxysporum f. sp. lycopersici, with compound 4t exhibiting the highest inhibitory effect.