Synthesis of some novel α-substituted phosphonic acids by Nano-SnCl4/SiO2 as antimicrobial agents

Khabnadideh, Soghra; Emami, Leila; Rezaei, Zahra; Zomorodian, Kamiar; Zamani, Leila

doi:10.30476/tips.2025.107987.1309

Synthesis of some novel α-substituted phosphonic acids by Nano-SnCl4/SiO2 as antimicrobial agents

Document Type : Original Article

Authors

¹ Pharmaceutical Sciences Research Center, Shiraz University of Medical Sciences, Shiraz, Iran

² Department of Medical Mycology and Parasitology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran

10.30476/tips.2025.107987.1309

Abstract

α-Substituted phosphonic acids exhibit promising antifungal activity by targeting key fungal metabolic pathways. Their structural versatility allows for enhanced binding affinity to fungal enzymes, inhibiting growth and virulence. These compounds demonstrate broad-spectrum efficacy against resistant strains, including Candida and Aspergillus species. Further optimization could lead to novel antifungal agents with reduced toxicity and improved pharmacokinetics. In this study, a series of α-substituted phosphonic acids (4a-4c) were synthesized using Nano-SnCl₄/SiO₂ as a catalyst in an ethanolic solution under reflux conditions with good yields. The chemical structures of the new compounds were confirmed by spectroscopic methods, including ¹H-NMR, ¹³C-NMR, and ³¹P-NMR. The synthesized compounds were evaluated for their antimicrobial activities. The broth microdilution method, as recommended by the Clinical and Laboratory Standards Institute, was used to determine the antifungal and antibacterial activities of the new compounds. The antimicrobial evaluation was tested against six different species of yeasts and four species of bacteria. Fluconazole and ciprofloxacin were used as reference drugs. The results demonstrated that the presence of an electronegative group on the phenyl ring had a positive effect on antimicrobial potency.

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