Synthesis, ($E)$/($Z)$-isomerization, and DNA binding, antibacterial, and antifungal activities of novel oximes and $O$-substituted oxime ethers

Abstract

A series of novel positional oximes (2a-2d), O -methyl oxime ethers (3a-3d), and O -benzyl oxime ethers (4a-4d) were synthesized in high yields starting from their corresponding methyl 3-, 4-, 6-, and 13-keto tetradecanoates.The synthesized compounds were characterized by 1 H NMR, 13 C NMR, FT-IR, mass, and elemental analyses for their structures and ( E) /( Z) isomerizations. Their DNA binding abilities were investigated in vitro by agarose gel electrophoresis. The antibacterial and antifungal activities were tested also in vitro against eleven bacterial strains and three fungal strains. The relationship between the structure and the mentioned biological activities was discussed.Compound 2a showed good antibacterial activity against five types of bacteria. Compounds 2b, 2c, 2d, and 4d were effective against several microorganisms. Among these, 2a showed the best DNA binding, antibacterial, and antifungal activities. Therefore, 2a can be a pro-drug as an anticancer, antibacterial, and antifungal agent.

Synthesis and elastase inhibition activities of novel aryl, substituted aryl, and heteroaryl oxime ester derivatives

“…1 H‐NMR and 13 C‐NMR spectra of the synthesized ( 2a–e ; 3a–e ; 4a–e ) showed only one signal for methoxy and benzyloxy groups. According to the literature, ( E )‐signal resonated at lower field than ( Z )‐signal . NMR spectra of the obtained ( 2a–e ; 3a–e ; 4a–e ) were similar to the ppm values of ( E )‐signals as seen in the previous study .…”

“…According to the literature, ( E )‐signal resonated at lower field than ( Z )‐signal . NMR spectra of the obtained ( 2a–e ; 3a–e ; 4a–e ) were similar to the ppm values of ( E )‐signals as seen in the previous study . Therefore, the configuration of the compounds synthesized in this paper were attributed to ( E )‐structure.…”

“…In the previous study of our group, oxime and oxime ether derivatives of the keto methyl ester isomers with C 14 carbon chain were synthesized as their ( E/Z )‐mixtures . 1 H‐NMR and 13 C‐NMR of these isomers had given two signals especially for methoxy and benzyloxy peaks due to their existance percent.…”

“…Oxime and oxime ether derivatives are valuable starting compounds for synthesis of many natural, pharmaceutical, and cosmetic products. They show biological activities like antiprotozoan, antibacterial, antifungal, antioxidant, and DNA cleavage abilities …”

Synthesis and Characterization of Novel Aromatic Substituted γ- and δ-Ketoxime Esters

“…(45)(46)(47). In another work, hydroxyimino derivatives of keto esters were obtained also mainly as E isomer (24).…”