Design, synthesis and biological activity of hybrid antifungals derived from fluconazole and mebendazole.

A novel series of triazole alcohol antifungals bearing a 5-benzoylbenzimidazol-2-ylthio side chain have been designed and synthesized as hybrids of fluconazole (a typical triazole antifungal) and mebendazole (an anthelmintic agent with antifungal activity). The title compounds were synthesized via the reaction of an appropriate oxirane and desired 2-mercaptobenzimidazole. Although there was possibility for formation of different N-substituted or S-substituted products, the structures of final compounds were assigned as thioether congeners by using 13C NMR spectroscopy. The SAR analysis of the primary lead compounds (series A) was conducted by simplifying the 5-benzoylbenzimidazol-2-ylthio residue to the benzimidazol-2-ylthio (series B) or benzothiazol-2-ylthio side chain (series C), and modification of halogen substituent on the phenethyl-triazole scaffold. In general, series A (compounds 4a-e) containing 5-benzoylbenzimidazole scaffold showed better antifungal activity against Candida spp. and Cryptococcus neoformans than related benzimidazole and benzothiazole derivatives. The better results were obtained with the 4-chloro derivative 4b displaying MICs <0.063-1 µg/mL. Although, removing benzoyl group from compound 4b had negative effect on the activity, optimization of phenethyl-triazole scaffold by desired halogen substituent resulted in compound 5c being as potent as 4b. In vitro and in silico ADMET evaluations of the most promising compounds 4b and 5c indicated that the selected compounds have desirable ADMET properties in comparison to standard drug fluconazole. Docking simulation study demonstrated that the benzimidazol-2-ylthio moiety is responsible for the potent antifungal activity of these compounds.

Synthetic approaches and structural diversity of triazolylbutanols derived from voriconazole in the antifungal drug development.

Voriconazole (VCZ) was the first approved triazole antifungal drug with 1-(1H-1,2,4-triazol-1-yl)butan-2-ol substructure. This drug showed a broad spectrum of activity, especially against yeasts and molds, and opened a new avenue toward the novel class of systemic antifungal agents. Modification of 2-fluoropyrimidine in the side chain of VCZ resulted in a newer generation of triazolylbutanols including efinaconazole, albaconazole, ravuconazole, and isavuconazole with the favorable antifungal spectrum, enhanced pharmacokinetic properties, and tolerable toxicity profiles. Due to the importance of triazolylbutanols in the discovery and development of new antifungal agents, in this review we have focused on the synthetic approaches and structural diversity of triazolylbutanols derived from voriconazole. This comprehensive review provides highlighting scope for medicinal chemists for the design, synthesis and development of novel potential antifungal drugs having better activity, pharmacokinetic property and toxicity profile.

A review on the structures and biological activities of anti-Helicobacter pylori agents.

Helicobacter pylori is one of the main causal risk factor in the generation of chronic gastritis, gastroduodenal ulcers and gastric carcinoma. Thus, the eradication of H. pylori infection is an important way for preventing and managing the gastric diseases. Multiple-therapy with several antibacterial agents is used for the eradication of H. pylori infections; however the increase of resistance to H. pylori strains has resulted in unsatisfactory eradication and unsuccessful treatment. Furthermore, the combination therapy with high dosing leads to the disruption of intestinal microbial flora and undesired side effects. Therefore, the search for new therapeutic agents with high selectivity against H. pylori is a field of current interest. In recent years, diverse compounds originating from natural sources or synthetic drug design programs were evaluated and tried to optimize for applying against H. pylori. In this review, we have described various classes of anti-H. pylori compounds, their structure-activity relationship studies, and mechanism of actions, which could be useful for the development of new drugs for the treatment of H. pylori infections.

Current advances of triazole alcohols derived from fluconazole: Design, in vitro and in silico studies.

Currently, the available antifungal agents have significant clinical incompetency in terms of their clinical efficacy, antifungal spectrum, unfavorable pharmacokinetic profiles, substantial side effects and drug-drug interactions. Thus, the optimization and improvement of existing drugs and identification of new antifungal agents are urgently needed. Fluconazole is the first triazole alcohol drug with good in vivo efficacy against yeasts and well-known targets in fungal cells. However, the wide use of fluconazole as a first-line antifungal therapy has led to the development of resistance in clinical isolates of Candida species including Candida albicans and the emerging non-albicans Candida spp. In the last years, extensive efforts inflected to design and discovery of triazole alcohols derived from fluconazole by replacing one triazole ring with the proper side chain. In this paper, we have reviewed the structural modification of fluconazole to pursuit potent triazole alcohols with improved anti-Candida activity, and have highlighted their in vitro activities and in silico studies.