Molecular docking, design, synthesis and biological evaluation of novel 2,3-aryl-thiazolidin-4-ones as potent NNRTIs

Parsing structural fragments of thiazolidin-4-one based α-amylase inhibitors: A combined approach employing in vitro colorimetric screening and GA-MLR based QSAR modelling supported by molecular docking, molecular dynamics simulation and ADMET studies

α-Amylase (EC.3.2.1.1) is a ubiquitous digestive endoamylase. The abrupt rise in blood glucose levels due to the hydrolysis of carbohydrates by α-amylase at a faster rate is one of the main reasons for type 2 diabetes. The inhibitors prevent the action of digestive enzymes, slowing the digestion of carbs and eventually assisting in the management of postprandial hyperglycemia. In the course of developing α-amylase inhibitors, we have screened 2-aryliminothiazolidin-4-one based analogs for their in vitro α-amylase inhibitory potential and employed various in silico approaches for the detailed exploration of the bioactivity. The DNSA bioassay revealed that compounds 5c, 5e, 5h, 5j, 5m, 5o and 5t were more potent than the reference drug (IC₆₀ value = 22.94 ± 0.24 μg mL^-1). The derivative 5o with -NO₂ group at both the rings was the most potent analog with an IC₆₀ value of 19.67 ± 0.20 μg mL^-1 whereas derivative 5a with unsubstituted aromatic rings showed poor inhibitory potential with an IC₆₀ value of 33.40 ± 0.15 μg mL^-1. The reliable QSAR models were developed using the QSARINS software. The high value of R²_ext = 0.9632 for model IM-9 showed that the built model can be applied to predict the α-amylase inhibitory activity of the untested molecules. A consensus modelling approach was also employed to test the reliability and robustness of the developed QSAR models. Molecular docking and molecular dynamics were employed to validate the bioassay results by studying the conformational changes and interaction mechanisms. A step further, these compounds also exhibited good ADMET characteristics and bioavailability when tested for in silico pharmacokinetics prediction parameters.

Discovery of benzothiazole-based thiazolidinones as potential anti-inflammatory agents: anti-inflammatory activity, soybean lipoxygenase inhibition effect and molecular docking studies

Despite the greatest achievement in the development of anti-inflammatory agents in the last two decades, the current clinical drugs suffer from a variety of complications in community settings and hospital. There is still an urgent need to design novel molecules with better safety profile and with different molecular targets from those in current clinical use. The aim of this research was to discover a series of benzothiazole-based thiazolidinones with lipoxygenase (LOX) inhibitory activity as a mechanism of anti-inflammatory action. Carrageenan-induced mouse foot paw oedema assay was carried out to determine the anti-inflammatory activity, while LOX inhibition was examined through the conversion of sodium linoleate to 13-hydroperoxylinoleic acid. Molecular docking studies were performed using AutoDock 4.2 software. The anti-inflammatory activity of the title compounds was determined in a range of 18.4%-69.57%, where compound #3 was found to be the most potent (69.57%) and also to be more active than the reference drug indomethacin (47%). Moreover, compound #3 showed the highest LOX inhibitory activity with IC50 of 13 μM being less potent to that of the reference NDGA (IC50 = 1.3 μM). Compound #3 has been identified as lead compound for further modification in an attempt to improve anti-inflammatory and LOX inhibitory activities.

Caffeic and 3-(3,4-dihydroxyphenyl)glyceric acid derivatives as antimicrobial agent: biological evaluation and molecular docking studies

Herein we report the evaluation of the antimicrobial activity of some previously synthesized 3-(3,4-dihydroxyphenyl)glyceric acid in benzylated and in free 3,4 hydroxy groups in catechol moiety along with some caffeic and 3-(3,4-dihydroxyphenyl)glyceric acid amides using the microdilution method. The evaluation revealed that compounds showed in general moderate to low activity with MIC in range of 0.36-4.5 mg/mL. Compounds were also studied against three resistant bacteria strains MRSA (Methicillin-resistant Staphylococcus aureus), E. coli and P. aeruginosa. Seven out of ten compounds were more potent than reference drugs ampicillin and streptomycin against MRSA, while against another two resistant strains seven compounds showed low activity and the rest were inactive. Antifungal activity of the tested compounds was much better than antibacterial, with MIC in the range of 0.019-3.0 mg/mL. Compounds #7 and 15 showed good activity against all fungi tested, being more potent than ketoconazole and in some case even better than bifonazole used as reference drugs. Docking studies revealed that the most active compound #7 binds to the haem group of the enzyme in the same way as ketoconazole.

Thiazolidin-4-Ones as Potential Antimicrobial Agents: Experimental and In Silico Evaluation

Herein, we report computational and experimental evaluations of the antimicrobial activity of twenty one 2,3-diaryl-thiazolidin-4-ones. All synthesized compounds exhibited an antibacterial activity against six Gram-positive and Gram-negative bacteria to different extents. Thus, the MIC was in the range of 0.008-0.24 mg/mL, while the MBC was 0.0016-0.48 mg/mL. The most sensitive bacterium was S. Typhimurium, whereas S. aureus was the most resistant. The best antibacterial activity was observed for compound 5 (MIC at 0.008-0.06 mg/mL). The three most active compounds 5, 8, and 15, as well as compound 6, which were evaluated against three resistant strains, MRSA, P. aeruginosa, and E. coli, were more potent against all bacterial strains used than ampicillin. The antifungal activity of some compounds exceeded or were equipotent with those of the reference antifungal agents bifonazole and ketoconazole. The best activity was expressed by compound 5. All compounds exhibited moderate to good drug-likeness scores ranging from -0.39 to 0.39. The docking studies indicated a probable involvement of E. coli Mur B inhibition in the antibacterial action, while CYP51 inhibition is likely responsible for the antifungal activity of the tested compounds. Finally, the assessment of cellular cytotoxicity of the compounds in normal human MRC-5 cells revealed that the compounds were not toxic.