Synthesis and spectroscopic properties of 4,4′-bipyridine linker bioactive macrocycle boronate esters: photophysical properties and antimicrobial with antioxidant studies

Abstract

Boron compounds are among the most widely used disinfectant agents due to their broad-spectrum antimicrobial and antioxidant activity. However, it cannot be said that the antimicrobial properties of boronate esters or 4,4′-bipyridine (4,4′-bpy) linker bioactive macrocycle boronate esters have been not fully studied.In this context, we present the synthesis of 4,4′-bipyridine linker bioactive macrocycle boronate esters with a B←N host, which could efficiently decrease the cytotoxicity toward various bacteria. The newly synthesized bioactive macrocycle boronate esters adducted 4,4′-bipyridine with a B←N host for antimicrobial agents were characterized using melting point, elemental analysis, NMR (1H, 13C, and 11B) spectra, FT-IR spectra, UV-Vis spectra, fluorescence spectra, and LC-MS/MS spectrometry. According to the antimicrobial activity results, it was determined that the boron compounds showing the best activity were (1), (5), and (6). When evaluated in general, it was determined that these boron compounds exhibited higher activity than streptomycin, cefazolin, and chloramphenicol antibiotics. Also, antioxidant studies show that boronate esters (2), (3), (4), and (7) displayed activity very close to standards, (1), (5), (6) and (8) showed better activity than Trx and Prg standards. © 2021