Pyrano-coumarin hybrids as potential antimicrobial agents against MRSA strains: Design, synthesis, ADMET, molecular docking studies, as DNA gyrase inhibitors

Novel Pyrrolidine-bearing quinoxaline inhibitors of DNA Gyrase, RNA polymerase and spike glycoprotein

Anti-infective agents are a class of drugs used to prevent, treat, or control infections caused by microorganisms such as bacteria, viruses, fungi, and parasites. They play a crucial role in modern medicine, helping to reduce the severity of infections and, in many cases, save lives. This study aims at the design and synthesis of hybrid compounds containing quinoxaline, pyrrolidine, and an azo bridge to combat antimicrobial resistance, and evaluating their antimicrobial, antifungal, and antiviral activities against various pathogenic strains. Eight most potent bactericidal derivatives 2, 4, 5, 7, 9, 11, 12, and 13 were further assessed for their antibiofilm activity. Additionally, these compounds were tested for their inhibitory effects on DNA gyrase using a DNA supercoiling assay with IC50 ranging from 26.57 to 84.84 μM when compared to ciprofloxacin as standard drug. The antiviral activities were performed against HSV-1, H1N1 and SARS-CoV-2 viruses, which showed that compound 9 has the highest antiviral activity with IC50 = 0.32 µM, IC50 = 1.76 µM and 1.06 µM, respectively, as well as the best safety profile with CC50 = 30000 µM. Compound 9 displayed the highest SI value against HSV-1, H1N1 and SARS-CoV-2 with values of 93685, 17,034 and 28368, respectively. Compound 9 inhibited RdRp and spike glycoprotein (IC50 = 2.437 ± 0.102 and 1425.1 ± 55.3 nM; respectively). The physicochemical and pharmacokinetic properties of the most active compounds were screened to identify those with optimal drug-like characteristics. Molecular docking studies were conducted on the most effective compounds to elucidate their binding interactions and mechanisms of action.

Discovery of novel bicyclic and tricyclic cyclohepta[b]thiophene derivatives as multipotent AChE and BChE inhibitors, in-Vivo and in-Vitro assays, ADMET and molecular docking simulation

Alzheimer's disease (AD) is primarily caused by oxidative stress, hyperphosphorylated τ-protein aggregation, and amyloid-β deposition. Changes in dopaminergic and serotoninergic neurotransmitter pathways are linked to certain symptoms of AD. Derivatives of bicyclic and tricyclic cyclohepta[b]thiophene were developed to identify new potential candidates as acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitors for the treatment of AD. All synthesized compounds exhibited AChE inhibition with IC50 values below 15 μM, while all compounds exhibited BChE inhibition with IC50 values below 25 μM. Compounds 9 and 12 exhibited AChE inhibitory activities with IC50 values of 0.51 μM and 0.55 μM, respectively. Compounds 5 and 9 demonstrated excellent inhibitory activity against BChE with IC50 values of 2.9 μM and 2.48 μM, respectively. Compounds 9, 13, and 14 were found to be the most active in terms of the decrease in the escape latency time, with values comparable to that of Donepezil. Compounds 10, 11, and 12 exhibited promising effects on learning and memory. Compounds 5, 10, 11, and 12 exhibited promising SAP values of 70.67 %, 71.5 %, 74.33 % and 73.83 %, respectively. Other biomarkers were evaluated in rat brains including TAC, MDA, SOD, BDNF, IL-β and TNF-α. Fundamental features of ADMET have been computed in-silico for synthesized compounds. Molecular docking was performed to confirm the binding of the novel compounds to the targets.

Unlocking the Antibacterial Potential of Naphthalimide-Coumarins to Overcome Drug Resistance with Antibiofilm and Membrane Disruption Ability against Escherichia coli

Resistance by bacteria to available antibiotics is a threat to human health, which demands the development of new antibacterial agents. Considering the prevailing conditions, we have developed a library of new naphthalimide-coumarin moieties as broad-spectrum antibacterial agents to fight against awful drug resistance. Preliminary studies indicate that compounds 8e and 8h display excellent antibacterial activity against Escherichia coli, exceeding the performance of marketed drug amoxicillin. These drug candidates effectively inhibit biofilm formation and disrupt the biofilm virulence factor, which is accountable for the formation of strong biofilm. In addition to this, both compounds exhibit fast bactericidal properties, thus shortening the time of treatment and resisting the emergence of drug resistance for up to 20 passages. Further, biofunctional evaluation reveals that both compounds effectively disrupt the membrane, causing the leakage of cytoplasmic contents and loss in metabolic activity. Both compounds 8e and 8h efficiently induce the ROS, leading to the oxidation of GSH to GSSG, decreasing the GSH activity of the cell, and causing oxidative damage to the cells. Additionally, both compounds effectively bind with DNA to block DNA replication and form supramolecular complexes, thus exhibiting antibacterial activity. Moreover, these compounds readily bind human serum albumin with high binding constants and can be transported to the target site easily. These findings reveal that newly synthesized naphthalimide-coumarin conjugates have the potential to build as potent antibacterial agents and can be used further for clinical trials.

Ammar Y, A. Abu Ali O, Ragab A, Mahfoz AM, Abusaif MS. Fluorinated indeno-quinoxaline bearing thiazole moieties as hypoglycaemic agents targeting α-amylase, and α-glucosidase: synthesis, molecular docking, and ADMET studies

Inhibition of α-glucosidase and α-amylase are key tactics for managing blood glucose levels. Currently, stronger, and more accessible inhibitors are needed to treat diabetes. Indeno[1,2-b] quinoxalines-carrying thiazole hybrids 1-17 were created and described using NMR. All analogues were tested for hypoglycaemic effect against STZ-induced diabetes in mice. Compounds 4, 6, 8, and 16 were the most potent among the synthesised analogues. These hybrids were examined for their effects on plasma insulin, urea, creatinine, GSH, MDA, ALT, AST, and total cholesterol. Moreover, these compounds were tested against α-glucosidase and α-amylase enzymes in vitro. The four hybrids 4, 6, 8, and 16 represented moderate to potent activity with IC50 values 0.982 ± 0.04, to 10.19 ± 0.21 for α-glucosidase inhibition and 17.58 ± 0.74 to 121.6 ± 5.14 μM for α-amylase inhibition when compared to the standard medication acarbose with IC50=0.316 ± 0.02 μM for α-glucosidase inhibition and 31.56 ± 1.33 μM for α-amylase inhibition. Docking studies as well as in silico ADMT were done.

The role of current synthetic and possible plant and marine phytochemical compounds in the treatment of acne

Acne is a long-standing skin condition characterized by plugged hair follicles due to the accumulation of dead skin cells, sebum, and Propionibacterium acnes (P. acnes) bacteria, causing inflammation, and the formation of pimples or lesions. Acne was recognized in the ancient times by the ancient Egyptians, Greeks, and Romans. Since ancient times, folk medicine from different cultures have comprised herbal and natural products for the treatment of acne. Current acne medications include antibiotics, keratolytics, corticosteroids, in addition to hormonal therapy for women. However, these conventional drugs can cause some serious side effects. And therefore, seeking new safe treatment options from natural sources is essential. Plants can be a potential source of medicinal phytochemicals which can be pharmacologically active as antibacterial, antioxidant, anti-inflammatory, keratolytic and sebum-reducing. Organic acids, obtained from natural sources, are commonly used as keratolytics in dermatology and cosmetology. Most of the promising phytochemicals in acne treatment belong to terpenes, terpenoids, flavonoids, alkaloids, phenolic compounds, saponins, tannins, and essential oils. These can be extracted from leaves, bark, roots, rhizomes, seeds, and fruits of plants and may be incorporated in different dosage forms to facilitate their penetration through the skin. Additionally, medicinal compounds from marine sources can also contribute to acne treatment. This review will discuss the pathogenesis, types and consequences of acne, side effects of conventional treatment, current possible treatment options from natural sources obtained from research and folk medicine and possible applied dosage forms.