Antibacterial and Antifungal Activity of Some 2- And 1,2-Substituted Benzimidazole Derivatives

Abstract

Benzimidazoles are a large class of compounds with many clinical and pharmacological applications. At present, there is an intense and renewed effort to synthetize new derivatives starting from the well-known benzimidazole moiety and to explore their properties. Due to the increasing antibiotic resistance of pathogens, a major objective is to find new efficient anti-bacterial agents. In this context, the study was carried out in order to estimate the antimicrobial potential of four 2-and 1,2-substituted benzimidazole derivatives already known to have photoprotective properties. Their antimicrobial capacity was assessed by diffusimetric tests by using 13 bacterial and 7 Candida strains and further completed by Minimum Inhibitory Concentration (MIC), and time-kill assay. The mean values of MIC varied between a minimum of 87.5 µg/mL and a maximum of 200 µg/mL in the Staphylococcus group, while for Candida values between 104.6 µg and 151.78 µg/mL were recorded. The results demonstrate a significant inhibitory activity against Gram-positive bacteria and Candida strains. Experiments of time-kill carried out on Candida showed a concentration-dependent activity pattern. RezumatBenzimidazolii sunt o clasă mare de compuși cu numeroase aplicații în practica clinică și farmacologie datorită proprietăților lor bioactive valoroase. În prezent, există un efort intens de a sintetiza noi derivați plecând de binecunoscutul nucleu benzimidazolic și de a le explora proprietățile. În acest context, studiul a fost realizat cu scopul de a estima capacitatea antimicrobiană a patru derivați substituiți 2-și 1,2-ai benzimidazolului, cunoscuți pentru proprietățile lor fotoprotectoare. Potențialul antimicrobian a fost evaluat prin testul difuzimetric, determinarea concentrației minime inhibitorii și prin evaluarea mortalității microorganismelor în funcție de timp. Valoarea medie a concentrației minime inhibitorii (CMI) a variat între 87,5 µg/mL și 200 µg/mL la Staphylococcus, în timp ce la Candida s-au înregistrat valori cuprinse între 104,6 µg/mL și 151,78 µg/mL. Rezultatele demonstrează o activitate inhibitorie semnificativă față de bacteriile Gram-pozitive și față de tulpinile de Candida. Experimentele asupra mortalității celulare în timp, realizate pe tulpinile de Candida, au evidențiat un model de acțiune dependent de concentrație.

Synthesis, Spectral Characterization and Molecular Docking Studies of New N3-Aryl- And N3-Alkyl-Barbituric Acid Derivatives With Potential Local Anaesthetic Action

“…Numerous azoles (pyrazole and imidazole), as well as their derivatives, have been found to possess specific pharmacological activities because of their interesting properties and their structure-biological activities relationships. A lot of pyrazoles compounds are already used in therapy due to their antibacterial, antifungal, analgesic, antipyretic, antitumor, β-blocking, antihypertensive, antihistamine, or local anaesthetic action [1][2][3][4][5]. Recently, a real progress in the drug design of local anaesthetics was made as a consequence of elucidation of the most complex membrane structures that include voltage-gated sodium channels.…”