Synthesis and antibacterial activity of pyridinium-tailored aromatic amphiphiles

Synthesis of novel 1,2,4-triazole derivatives containing the quinazolinylpiperidinyl moiety and N-(substituted phenyl)acetamide group as efficient bactericides against the phytopathogenic bacterium Xanthomonas oryzae pv. oryzae

“…4 The most typical symptoms of tobacco plants infected by this pathogen are rapid yellowing and wilting of tobacco leaves. 5 Although some commercial antibactericidal agents (i.e., Bismerthiazol and Thiodiazole copper) are currently available on the market for ghting against these two bacterical diseases, however, poor efficiency, high phytotoxicities, high residue levels, adverse effects on the natural environment and growing problems of antibacterial resistance related with the utilization of these bactericides are attracting increasing attention from agricultural chemists. Therefore, the search of new and more efficient antibacterial agents still remains an urgent task in the agrochemical eld.…”

Antibacterial and Antifungal Activities of 2‐(substituted ether)‐5‐(1‐phenyl‐5‐(trifluoromethyl)‐1H‐pyrazol‐4‐yl)‐1,3,4‐oxadiazole Derivatives

“…A subsequent reaction with halogenated reagents provided the target molecules ( 6b–6l ). While compounds 7a and 7b were synthesized via incubating the bromide‐tailored intermediates in pyridine at 60°C . All the structures were characterized by IR, 1 H NMR (Figure S1–S14, supplementary data), 13 C NMR, MS, and elemental analysis.…”

“…For example, an electron‐donating group (−CH 3 , 6j , 40.2%, 200 μg/mL) on the benzyl moiety exerted higher antibacterial activity than that of other electron‐withdrawing groups (4‐Cl, 6h , 22.4%; 4‐F, 6i , 32.3%; 4‐CF 3 , 6k , 22.1%). For compounds 7a and 7b , the bioactivity was enhanced with the increase in the alkyl chains, suggesting that even slight changes in the ratio between hydrophobic and hydrophilic parts will affect their bioactivities .…”

“…Herein, the amide bond was replaced by 1,3,4‐oxadiazole, which was verified as one of the key functional substructures in the exploration and construction of new agrochemicals . Meanwhile, pyridinium scaffolds can modulate the physical properties of a molecule, and bioactivities are often enhanced by introducing the pyridinium moieties into target compounds . Therefore, a series of 1‐phenyl‐5‐(trifluoromethyl)‐1 H ‐pyrazole derivatives bearing 1,3,4‐oxadiazole (or both 1,3,4‐oxadiazole and pyridinium groups) were constructed and evaluated their antibacterial and antifungal activities.…”

EDC‐Mediated Grafting of Quaternary Ammonium Salts onto Chitosan for Antibacterial and Thermal Properties Improvement

“…In order to improve chitosan properties, attention has been recently paid to chitosan chemical modification by introducing, for example, quaternary ammonium moieties into the polymer backbone, which represents one of the most promising strategies for antimicrobial materials preparation . Quaternary ammonium salts like quinolinium, benzalkonium, and pyridinium bromide have been used as antibacterial, antiviral, and antifungal agents . The incorporation of these quaternary ammonium moieties into chitosan architecture, represents one of the most promising strategies to improve its antibacterial behavior …”