Isoflavonoid and Furanochromone Natural Products as Potential DNA Gyrase Inhibitors: Computational, Spectral, and Antimycobacterial Studies

Lewis Acid-Driven Multicomponent Reactions Enable 2-Alkyl Chromanones with Anticancer Activities

2-Alkyl chromanone scaffold has become prominent in pharmaceuticals and natural compounds. Consequently, devising robust strategies for synthesizing 2-alkyl chromanones remains crucial. Here, multicomponent reactions were employed to synthesize 2-alkyl chromanones containing an oxazole moiety using 3-formylchromones, amines, and N-propargylamides as reactants. This method utilizes readily available feedstocks with a catalytic amount of Zn(OTf)2 and exhibits an impressive substrate scope compared to existing methods. Importantly, the synthesized compounds demonstrated highly selective anticancer activity against the DU145 cell line.

Insights into in-vitro studies and molecular modelling of the antimicrobial efficiency of 4-chlorobenzaldehyde and 4-methoxybenzaldehyde derivatives

Owing to the significant gap in the knowledge and understanding of the mechanisms of antimicrobial action and the development of resistance, the optimization of antimicrobial therapies therefore becomes a necessity. It is on this note, that this study seeks to both experimentally and theoretically investigate the antimicrobial efficiency of two synthesized compounds namely; 1-((4-methoxyphenyl) (morpholino)methyl)thiourea (MR1) and diethyl 4-(4-chlorophenyl)-2,6-diphenyl-1,4-dihydropyridine-3,5-dicarboxylate (HRC). Utilizing the density functional theory (DFT), the compounds were optimized at ωB97XD/6-31++G(2d, 2p) level of theory. This provided a clear explanation for their distinct reactivity and stability potentials. More so, the natural bond orbital (NBO) analysis confirmed strong intra and intermolecular interactions, which agreed with the calculated reactivity parameters and density of states (DOS). Upon assessing the antimicrobial efficacy of the synthesized compounds, it was found that they exhibited lower activity against Enterobacter and A. niger, but considerable activity against Moraxella. In contrast, they showed higher activity against B. subtilis and Trichophyton, indicating that the compounds are more effective against gram-positive bacteria than gram-negative ones. Hence, it can be asserted that the synthesized compounds have superior antifungal action than antibacterial activity. A fascinating aspect of the data is that they show interactions that are incredibly insightful, totally correlating with the simulations of both molecular docking and molecular dynamics. Therefore, the alignment between experimental findings and computational simulations strengthens the validity of the study's conclusions, emphasizing the significance of the synthesized compounds in the context of optimizing antimicrobial therapies.Communicated by Ramaswamy H. Sarma.

Chrysin based pyrimidine-piperazine hybrids: design, synthesis, in vitro antimicrobial and in silico E. coli topoisomerase II DNA gyrase efficacy

Ten chrysin-based pyrimidine-piperazine hybrids have been evaluated in vitro for antimicrobial activity against eleven bacterial and two fungal strains. All compounds 5a-j exhibited moderate to good inhibition, with MIC values ranging from 6.25 to 250 µg/ml. At 6.25 µg/ml and 12.5 µg/ml MIC values, respectively, compounds 5b and 5h demonstrated the most promising potency against E. coli, outperforming ampicillin, chloramphenicol, and ciprofloxacin. None of the substances had the same level of action as norfloxacin. 5a, 5d, 5g, 5h, and 5i have exhibited superior antifungal efficacy than Griseofulvin against C. albicans with 250 µg/ml MIC. All the compounds were also individually docked into the E. coli DNA gyrase ATP binding site (PDB ID: 1KZN) and CYP51 inhibitor (PDB ID: 5V5Z). The most active compound, 5h and 5g displayed a Glide docking score of - 5.97 kcal/mol and - 10.99 kcal/mol against DNA gyrase and 14α-demethylase enzyme CYP51 respectively. Potent compounds 5b, 5h, and 5g may be used to design new, innovative antimicrobial agents, according to in vitro, ADMET, and in silico biological efficacy analyses.

In silico drug design strategies for discovering novel tuberculosis therapeutics

INTRODUCTION

Tuberculosis remains a significant concern in global public health due to its intricate biology and propensity for developing antibiotic resistance. Discovering new drugs is a protracted and expensive endeavor, often spanning over a decade and incurring costs in the billions. However, computer-aided drug design (CADD) has surfaced as a nimbler and more cost-effective alternative. CADD tools enable us to decipher the interactions between therapeutic targets and novel drugs, making them invaluable in the quest for new tuberculosis treatments.

AREAS COVERED

In this review, the authors explore recent advancements in tuberculosis drug discovery enabled by in silico tools. The main objectives of this review article are to highlight emerging drug candidates identified through in silico methods and to provide an update on the therapeutic targets associated with Mycobacterium tuberculosis.

EXPERT OPINION

These in silico methods have not only streamlined the drug discovery process but also opened up new horizons for finding novel drug candidates and repositioning existing ones. The continued advancements in these fields hold great promise for more efficient, ethical, and successful drug development in the future.

In-silico and in-vitro evaluation of antifungal bioactive compounds from Streptomyces sp. strain 130 against Aspergillus flavus

Streptomyces spp. are considered excellent reservoirs of natural bioactive compounds. The study evaluated the bioactive potential of secondary metabolites from Streptomyces sp. strain 130 through PKS-I and NRPS gene-clusters screening. GC-MS analysis was done for metabolic profiling of bioactive compounds from strain 130 in the next set of experiments. Identified antifungal compounds underwent ADMET analyses to screen their toxicity. All compounds' molecular docking was done with the structural gene products of the aflatoxin biosynthetic pathway of Aspergillus flavus. MD simulations were utilized to evaluate the stability of protein-ligand complexes under physiological conditions. Based on the in-silico studies, compound 2,4-di-tert butyl-phenol (DTBP) was selected for in-vitro studies against Aspergillus flavus. Simultaneously, bioactive compounds were extracted from strain 130 in two different solvents (ethyl-acetate and methanol) and used for similar assays. The MIC value of DTBP was found to be 314 µg/mL, whereas in ethyl-acetate extract and methanol-extract, it was 250 and 350 µg/mL, respectively. A mycelium growth assay was done to analyze the effect of compounds/extracts on the mycelium formation of Aspergillus flavus. In agar diffusion assay, zone of inhibitions in DTBP, ethyl-acetate extract, and methanol extract were observed with diameters of 11.3, 13.3, and 7.6 mm, respectively. In the growth curve assay, treated samples have delayed the growth of fungi, which signified that the compounds have a fungistatic nature. Spot assay has determined the fungal sensitivity to a sub-minimum inhibitory concentration of antifungal compounds. The study's results suggested that DTBP can be exploited for antifungal-drug development.Communicated by Ramaswamy H. Sarma.

In Silico Design, Synthesis, and Evaluation of Novel Enantiopure Isoxazolidines as Promising Dual Inhibitors of α-Amylase and α-Glucosidase

Isoxazolidine derivatives were designed, synthesized, and characterized using different spectroscopic techniques and elemental analysis and then evaluated for their ability to inhibit both α-amylase and α-glucosidase enzymes to treat diabetes. All synthesized derivatives demonstrated a varying range of activity, with IC50 values ranging from 53.03 ± 0.106 to 232.8 ± 0.517 μM (α-amylase) and from 94.33 ± 0.282 to 258.7 ± 0.521 μM (α-glucosidase), revealing their high potency compared to the reference drug, acarbose (IC50 = 296.6 ± 0.825 µM and 780.4 ± 0.346 µM), respectively. Specifically, in vitro results revealed that compound 5d achieved the most inhibitory activity with IC50 values of 5.59-fold and 8.27-fold, respectively, toward both enzymes, followed by 5b. Kinetic studies revealed that compound 5d inhibits both enzymes in a competitive mode. Based on the structure-activity relationship (SAR) study, it was concluded that various substitution patterns of the substituent(s) influenced the inhibitory activities of both enzymes. The server pkCSM was used to predict the pharmacokinetics and drug-likeness properties for 5d, which afforded good oral bioavailability. Additionally, compound 5d was subjected to molecular docking to gain insights into its binding mode interactions with the target enzymes. Moreover, via molecular dynamics (MD) simulation analysis, it maintained stability throughout 100 ns. This suggests that 5d possesses the potential to simultaneously target both enzymes effectively, making it advantageous for the development of antidiabetic medications.

LC-MS profiling, in vitro and in silico C-ABL kinase inhibitory approach to identify potential anticancer agents from Dalbergia sissoo leaves

Belonging to the Fabaceae family, Dalbergia sissoo, a versatile plant, has gained prominence for its potent medicinal attributes, especially antipyretic, anti-inflammatory, and cardioprotective properties, as well as the use of its leaf juice in cancer treatment. Despite these recognized applications by natives and tribals, comprehensive insight into its biological activities and chemical composition remains limited. This study aimed to explore the cytotoxic potential of sequentially extracted leaf extracts from Dalbergia sissoo using various solvents, aiming to unveil the array of phytochemicals through LC-MS profiling. Among the extracts evaluated, the extract employing methanol:water extracting media (HN-2) appeared with the most remarkable results in both phytochemical diversity and biological activity. Furthermore, in vitro results of HN-2's in vitro anticancer efficacy were confirmed through in silico molecular docking and molecular dynamics simulation. These analyses demonstrated its ability to inhibit C-ABL kinase within leukemia K562 cells, directing that Dalbergia sissoo leaves serve as a bioactive agent reservoir. Consequently, this suggests that the Dalbergia sissoo plant is a potential source of bioactive compounds that can be used as a precursor for developing new cancer inhibitors, mainly targeting leukemia.