Synthesis, antimicrobial, and anti-inflammatory activities of acetamido pyrrolyl azoles

Molecular properties prediction, synthesis, and antimicrobial activity of bis(azolyl)sulfonamidoacetamides

A library of bis(azolyl)sulfonamidoacetamides was prepared by the reaction of azolylsulfonylamines with azolylchloroacetamides in the presence of pyridine/4-(dimethylamino)pyridine (DMAP) under ultrasonication. The reaction proceeded well with DMAP, resulting in a higher yield of the products. The antimicrobial activity of the compounds indicated that N-{5-[N-(2-{[4-(4-chloro-1H-pyrrol-2-yl)-1H-imidazol-2-yl)amino}-2-oxoethyl)sulfamoyl]-4-phenylthiazol-2-yl}benzamide (22a), N-{5-[N-(2-{[4-(4-chloro-1H-pyrrol-2-yl)-1H-imidazol-2-yl]amino}-2-oxoethyl)sulfamoyl]-4-(4-chlorophenyl)thiazol-2-yl}benzamide (22c), and N-{5-[N-(2-{[4-(4-chloro-1H-pyrrol-2-yl)-1H-imidazol-2-yl]amino}-2-oxoethyl)sulfamoyl]-4-(4-chloro-phenyl)-1H-imidazol-2-yl}benzamide (24c) exhibited a low minimal inhibitory concentration (MIC) against Bacillus subtilis, equal to the standard drug, chloramphenicol. Compounds 22c and 24c also showed low MICs against Aspergillus niger, equal to the standard drug, ketoconazole. The molecular properties of the synthesized molecules were studied to identify druglikeness properties of the target compounds. On the basis of molecular properties prediction, 19a, 19b, 20b, 20c, 21a-c, 22b, 22c, and 23a-c can be treated as drug candidates.

Synthesis of imidazole-pyrazole conjugates bearing aryl spacer and exploring their enzyme inhibition potentials

Developing improved enzyme inhibitors is an effective therapy to counter various diseases. Aiming to build up biologically active templates, a new series of bis-diazoles conjugated with an aryl linker was designed and prepared through a convenient synthetic approach. Synthesized derivatives 6(a-m), having different substitutions at the 2^nd position of the imidazole nucleus, depict the scope of present study. These compounds were characterized through spectroscopic methods and further examined for their in vitro enzyme inhibitory potentials against two selected enzymes: α-glucosidase and lipoxygenase (LOX). Overall, this series was found to be effective against α-glucosidase and moderately active against LOX enzyme. Compound 6k was the most potent α-glucosidase inhibitor with IC₅₀ = 54.25 ± 0.67 µM as compared to reference drug acarbose (IC₅₀ = 375.82 ± 1.76 µM). The docked conformation revealed the involvement of substituent's heteroatoms with amino acid residue Gly280 through hydrogen bonding. The most active LOX inhibitor was 6a with IC₅₀ = 41.75 ± 0.04 µM as compared to standard baicalein (IC₅₀ = 22.4 ± 1.3 µM). Docking model of 6a suggested the strong interaction of imidazole's nitrogen with iron atom of the active pocket of enzyme. Other features like lipophilicity, bulkiness of compounds, pi-pi interactions and/or pi-alkyl interactions also affected the inhibiting potentials of all prepared scaffolds.

2-Aminooxazole as a Novel Privileged Scaffold in Antitubercular Medicinal Chemistry

To obtain effective eradication of numerous infectious diseases such as tuberculosis, it is important to supply the medicinal chemistry arsenal with novel chemical agents. Isosterism and bioisosterism are widely known concepts in the field of early drug discovery, and in several cases, rational isosteric replacements have contributed to improved efficacy and physicochemical characteristics throughout the hit-to-lead optimization process. However, sometimes the synthesis of isosteres might not be as straightforward as that of the parent compounds, and therefore, novel synthetic strategies must be elaborated. In this regard, we herein report the evaluation of a series of N-substituted 4-phenyl-2-aminooxazoles that, despite being isosteres of a widely used nucleus such as the 2-aminothiazole, have been only seldom explored. After elaboration of a convenient synthetic strategy, a small set of 2-aminothiazoles and their 2-aminooxazole counterparts were compared with regard to antitubercular activity and physicochemical characteristics.

Synthesis and Analysis of 1-Methyl-4-Phenyl-1H-Imidazol-2-Amine

A practical synthetic route to an important pharmaceutical intermediate 1-methyl-4-phenyl-1H-imidazol-2-amine, via a three-step sequence involving cyclisation, hydrolysis and methylation, is reported. In the process of optimisation, a novel chemical entity was isolated and confirmed to be 2,6-diphenyl-1H-imidazo[1,2-a]imidazole by MS, 1H NMR and 13C NMR. The scale-up experiment was carried out to provide 1-methyl-4-phenyl-1H-imidazol-2-amine in 27.4% total yield.

Synthesis of Oxadiazole-Thiadiazole Hybrids and Their Anticandidal Activity

In the field of infection management, it is a major challenge to discover a potent and safe antifungal agent due to the emergence of resistant strains. Hence, the goal of this paper is to design and synthesize novel oxadiazole-thiadiazole hybrid compounds (6a-6s) and evaluate their antifungal activity. The structures of synthesized compounds were elucidated by various methods including FT-IR, ¹H-NMR, ¹³C-NMR and HR-MS spectral data. Compounds were tested against four Candida species by broth microdilution assay. Compounds 6e, 6k and 6r, bearing a nitro group, showed significant antifungal activity against all fungi with minimum inhibitory concentration (MIC) in the range of 0.78-3.12 µg/mL. These compounds were also screened for their in vitro cytotoxic effects by MTT assay and detected as nontoxic at their active concentrations against Candida strains. To examine the effects of these compounds on ergosterol biosynthesis, the LC-MS-MS method, which is based on quantification of ergosterol level in C. krusei, was carried out. Finally, the most active molecule (6e) was docked in the active site of the lanosterol 14α-demethylase enzyme, and it was determined that there is a strong interaction between the compound and enzyme.