Synthetic modifications in ethyl 2-amino-4-methylthiazole-5-carboxylate: 3D QSAR analysis and antimicrobial study

An Overview of the Structure-Activity Relationship in Novel Antimicrobial Thiazoles Clubbed with Various Heterocycles (2017-2023)

Antimicrobial resistance is an increasing problem for global public health. One of the strategies to combat this issue is the synthesis of novel antimicrobials through rational drug design based on extensive structure-activity relationship studies. The thiazole nucleus is a prominent feature in the structure of many authorized antimicrobials, being clubbed with different heterocycles. The purpose of this review is to study the structure-activity relationship in antimicrobial thiazoles clubbed with various heterocycles, as reported in the literature between 2017 and 2023, in order to offer an overview of the last years in terms of antimicrobial research and provide a helpful instrument for future research in the field.

Synthesis, molecular docking, DFT study, and in vitro antimicrobial activity of some 4-(biphenyl-4-yl)-1,4-dihydropyridine and 4-(biphenyl-4-yl)pyridine derivatives

The evolution of microbial resistance necessitates the development of new antimicrobial drugs that are more effective than those currently on the market. To address this problem, we have prepared a series of novel 4-(biphenyl-4-yl)-1,4-dihydropyridine and 4-(biphenyl-4-yl)pyridine derivatives via Hantzsch reaction using nine different compounds containing active methylene group. IR, NMR, and mass spectra were used to determine the structures. Using ampicillin and griseofulvin as standards, the titled compounds were investigated for their antibacterial activity against different bacteria and fungi. Compounds 1f, 1g, 2f, and 2g have the best antibacterial activity against Gram-negative bacteria (minimum inhibitory concentration = 50 μg/ml), while 1f, 1h, 2g, and 2h have high antifungal activity against Candida albicans (minimum inhibitory concentration = 100 μg/ml). To gain a better understanding of the binding process and affinity for the bacterial Staphylococcus epidermidis protein, researchers used molecular docking and molecular mechanics, as well as the generalized Born model and solvent accessibility-based binding free energy. The active compounds 1g, 1h, and 2f have good docking scores of -5.575, -5.949, and -5.234, respectively, whereas compound 2c has the greatest docking score (-6.23). The HOMO-LUMO energy gap and molecular electrostatic potential were used to evaluate the reactivity of promising compounds, which were then associated with antibacterial efficacy.