Determination of the inhibition profiles of pyrazolyl-thiazole derivatives against aldose reductase and α-glycosidase and molecular docking studies

Novel triazole bridged quinoline-anthracene derivatives: synthesis, characterization, molecular docking, evaluation of electronic and enzyme inhibitory properties

Two novel quinoline-anthracene conjugates comprising styrylquinoline and anthracene moieties linked by triazole bridges were designed and synthesized in good yields. These molecules were determined for some metabolic enzymes activities. Results indicated that the synthetic molecules exhibited powerful inhibitory actions against all aims as compared to the control molecules. Ki values of novel compound QA-1 for hCA I, hCA II, AChE, and α-glycosidase enzymes were obtained of 20.18 ± 2.46 µM, 14.63 ± 1.14 µM, 71.48 ± 7.76 nM, 401.35 ± 36.84 nM, respectively. Both compounds showed promising candidate complexes for drug development with considerable in vitro different enzymes inhibitory activities. The binding conformations patterns and interaction of QA-1 and QA-2 compounds with α-glucosidase, acetycholinesterase, carbonic anhydrase-I and carbonic anhydrase-II enzymes were investigated through molecular docking profiles. The docking outputs are consistent with the Ki and IC50 values of novel compounds. Three dimensional geometries and electronic properties of the title compounds were obtained by the applicational computational approach at B3LYP/6-31++G(d,p) level of theory.Communicated by Ramaswamy H. Sarma.

Antidiabetic effects of two naphthoquinones from the branches and leaves of Tectona grandis and possible mechanism

Tectona grandis is a Dai medicine that plays an important role in traditional medicine in India, Myanmar, West Africa, and Yunnan Province in China. T. grandis was recorded as an anti-diabetic herb in the Ayurvedic Pharmacopoeia; however, its potential antidiabetic components and possible mechanisms of action have almostly not been described to far. To completely comprehend the pharmacological components and therapeutic potential of T. grandis, we isolated chemical components from the plant's leaves and branches, evaluated their antidiabetic activities, and explored the possible mechanisms of active compounds using molecular docking and network pharmacology. In this study, two new quinones (1-2) and eighteen known compounds (3-20) were isolated and identified from T. grandis. Except for the new quinones 1 and 2, compounds 4, 11-12, 14-15, 18-20 were separated from T. grandis for the first time. The naphthoquinones 1 and 3 showed significant antidiabetic activities in α-glucosidase inhibition assay (IC50: 92.52 ± 5.05 and 45.37 ± 1.50 μM, respectively), glucose uptake assay (Inhibition rate: 63.90 ± 1.04 % and 65.41 ± 1.96 %, respectively) and preadipocyte differentiation inhibition assay (Lipid droplet content decreased by 8.49 ± 0.71 % and 13.89 ± 0.29 %, respectively, compared to the model group). Our study also revealed that T. grandis might treat diabetes by targeting CASP3, ESR1, and PTGS2. This study provided important support for the traditional usage of T. grandis as an antidiabetic herb by identifying its antidiabetic components and possible mechanism.

Insight into the therapeutic potential of pyrazole-thiazole hybrids: A comprehensive review

Several pyrazole-thiazole hybrids featuring two potentially bioactive pharmacophores with or without linker have been synthesized using the molecular hybridization approach as target structures by medicinal chemists to modulate multiple drug targets simultaneously. The presented review aims to provide an overview of the diversified and wide array of pharmacological activities of these hybrids bestowing anticancer, antifungal, antibacterial, analgesic, anti-inflammatory, antioxidant, antitubercular, antiviral, antiparasitic, and miscellaneous activities. The structure-activity relationships and potential mechanism of action are also reviewed to shed light on the development of more effective and biotargeted candidates. This review focuses on the latest research advances in the biological profile of pyrazole-thiazole hybrids reported from 2015 to the present, providing medicinal researchers with a comprehensive platform to rationally design and develop more promising pyrazole-thiazole hybrids.

Synthesis, molecular modelling, and biological evaluation of novel quinoxaline derivatives for treating type II diabetes

Quinoxalines are benzopyrazine derivatives with significant therapeutic impact in the pharmaceutical industry. They proved to be useful against inflammation, bacterial, fungal, viral infection, diabetes and other applications. Very recently, in January 2024, the FDA approved new quinoxaline containing drug, erdafitinib for treatment of certain carcinomas. Despite the diverse biological activities exhibited by quinoxaline derivatives and the role of secretory phospholipase A2 (sPLA2) in diabetes-related complications, the potential of sPLA2-targeting quinoxaline-based inhibitors to effectively address these complications remains unexplored. Therefore, we designed novel sPLA2- and α-glucosidase-targeting quinoxaline-based heterocyclic inhibitors to regulate elevated post-prandial blood glucose linked to patients with diabetes-related cardiovascular complications. Compounds 5a-d and 6a-d were synthesised by condensing quinoxaline hydrazides with various aryl sulphonyl chlorides. Biological screening revealed compound 6a as a potent sPLA2 inhibitor (IC50 = 0.0475 µM), whereas compound 6c most effectively inhibited α-glucosidase (IC50 = 0.0953 µM), outperforming the positive control acarbose. Moreover, compound 6a was the best inhibitor for both enzymes. Molecular docking revealed pharmacophoric features, highlighting the importance of a sulfonohydrazide moiety in the structural design of these compounds, leading to the development of potent sPLA2 and α-glucosidase inhibitors. Collectively, our findings helped identify promising candidates for developing novel therapeutic agents for treating diabetes mellitus.

Eco-friendly Regioselective Synthesis, Biological Evaluation of Some New 5-acylfunctionalized 2-(1H-pyrazol-1-yl)thiazoles as Potential Antimicrobial and Anthelmintic Agents

The present study describes an eco-friendly NBS-assisted regioselective synthesis of new 5-acylfunctionalized 5-acylfunctionalized 2-(1H-pyrazol-1-yl)thiazoles by condensation of 3,5-dimethyl-1H-pyrazole-1-carbothioamide with unsymmetrical 1,3-diketones under solvent-free conditions. The structural elucidation of the newly synthesized compounds was accomplished using various spectroscopic techniques viz. FTIR, NMR and mass spectrometry. All the newly synthesized compounds were examined for their in vitro antimicrobial potential against both pathogenic gram positive and gram negative bacterial and fungal species as well as anthelmintic activity against Pheretima posthuma earthworms. The results of antimicrobial activity revealed that all tested compounds 3 a-j showed excellent antimicrobial potential particularly against S. aureus. It was also observed that compounds 3 e and 3 i (MIC=62.5 μg/mL) showed greater potency against E. coli, whereas compounds 3 a and 3 h (MIC=50 μg/mL and 62.5 μg/mL) demonstrated better activity against P. aeruginosa and compound 3 i (MIC=62.5 μg/mL) exhibited superior activity against S. pyogenus when compared to standard drug Ampicillin (MIC=100μg/mL). Compound 3 e and 3 j revealed remarkable antifungal and anthelmintic activities. To find out binding interactions of target compounds with target proteins and pharmacokinetic parameters of the compounds, in silico investigations involving molecular docking studies and ADMET predictions were also performed.

Aldose reductase with quinolone antibiotics interaction: In vitro and in silico approach of its relationship with diabetic complications

Aldose reductase (AR, EC1.1.1.21), a member of the aldo-keto reductase family, is critically implicated in the pathogenesis of chronic complications associated with diabetes mellitus, including neuropathy, nephropathy, and retinopathy. Hyperglycemia-induced AR overactivity results in intracellular sorbitol accumulation, NADPH depletion, and oxidative stress. Consequently, AR is recognized as a key mediator of oxidative and inflammatory signaling pathways involved in diverse human pathologies such as cardiovascular diseases, inflammatory disorders, and cancer. This has sparked renewed interest in developing novel AR inhibitors (ARIs) with enhanced therapeutic profiles. In this study, we evaluated the inhibitory potential of five quinolone antibiotics-gatifloxacin, lomefloxacin, nalidixic acid, norfloxacin, and sparfloxacin-as ARIs relevant to various physiological and pathological conditions. Through comprehensive in vitro and in silico analyses, we explored these antibiotics' binding interactions and affinities within the AR active site. Our findings reveal that these quinolones moderately inhibit AR at micromolar concentrations, with inhibition constants (KIs) ranging from 1.03 ± 0.13 μM to 4.12 ± 0.51 μM, compared to the reference drug epalrestat (KI of 0.85 ± 0.06 μM). The combined in vitro and in silico results underscore significant interactions between these drugs and AR, suggesting their potential as therapeutic agents against the aforementioned pathological conditions. Furthermore, these insights will aid in optimizing clinical dosing regimens and mitigating unexpected drug-drug interactions when these antibiotics are co-administered with other treatments.

Design, synthesis, molecular docking, and dynamics studies of novel thiazole-Schiff base derivatives containing a fluorene moiety and the assessment of their antimicrobial and antioxidant activity

In this study, a series of eighteen fluorene-containing substituted thiazole derivatives were synthesized and characterized via spectral analyses. The proposed compounds were screened for their in vitro antimicrobial activity, and it was found that compound 2a displayed a significant zone of inhibition (20.3 ± 0.6 mm) against B. subtilis and compound 2b exhibited inhibitory activity (30.3 ± 0.6 mm) against a C. albicans fungal strain. Furthermore, antioxidant activity was evaluated for all analogues, where 2f exhibited a four-fold higher antioxidant capability (11.73 ± 1.22 μg mL-1) than the standard ascorbic acid. Oral bioavailability and toxicological parameters were considered, and most of the compounds satisfied Lipinski's rule of five and Veber's rule, except for one violation by a few derivatives. Molecular docking and molecular dynamics simulation were performed, providing more explicit ideas on the binding interaction and stability of compounds that exhibited wet lab activity. Average RMSD and RMSF values ranged between 0.5 Å and 2.5 Å, which indicated the stability of ligands inside the complex, yielding some engrossing insights.

Synthesis and biological studies of pyrimidine derivatives targeting metabolic enzymes

Novel synthesized pyrimidine derivatives were investigated against carbonic anhydrase isoenzymes I and II (hCA I and II), acetylcholinesterase (AChE), butyrylcholinesterase (BChE), α-glycosidase, and aldose reductase (AR) enzymes associated with some common diseases such as epilepsy, glaucoma, Alzheimer's disease, diabetes, and neuropathy. When the results were examined, novel synthesized pyrimidine derivatives were found to have effective inhibition abilities toward the metabolic enzymes. IC50 values and Ki values were calculated for each pyrimidine derivative and compared to positive controls. The synthesized novel pyrimidine derivatives exhibited Ki values in the range of 39.16 ± 7.70-144.62 ± 26.98 nM against hCA I, 18.21 ± 3.66-136.35 ± 21.48 nM toward hCA II, which is associated with different pathological and physiological processes, 33.15 ± 4.85-52.98 ± 19.86 nM on AChE, and 31.96 ± 8.24-69.57 ± 21.27 nM on BChE. Also, Ki values were determined in the range of 17.37 ± 1.11-253.88 ± 39.91 nM against α-glycosidase and 648.82 ± 53.74-1902.58 ± 98.90 nM toward AR enzymes. Within the scope of the study, the inhibition types of the novel synthesized pyrimidine derivatives were evaluated.

Thiadiazole and Thiazole Derivatives as Potential Antimicrobial Agents

BACKGROUND

This review summarizes data on heterocyclic systems with thiadiazole and thiazole fragments in molecules as promising antimicrobial agents.

INTRODUCTION

Thiadiazole and thiazole backbones are the most favored and well-known heterocycles, a common and essential feature of various drugs. These scaffolds occupy a central position and are the main structural components of numerous drugs with a wide spectrum of action. These include antimicrobial, antituberculous, anti-inflammatory, analgesic, antiepileptic, antiviral, and anticancer agents.

METHOD

The research is based on bibliosemantic and analytical methods using bibliographic and abstract databases, as well as databases of chemical compounds.

RESULT

This review reports on thiadiazole and thiazole derivatives, which have important pharmacological properties. We are reviewing the structural modifications of various thiadiazole and thiazole derivatives, more specifically, the antimicrobial activity reported over the last years, as we have taken this as our main research area. 80 compounds were illustrated, and various derivatives containing hydrazone bridged thiazole and pyrrole rings, 2-pyridine and 4-pyridine substituted thiazole derivatives, compounds containing di-, tri- and tetrathiazole moieties, spiro-substituted 4- thiazolidinone-imidazoline-pyridines were analyzed. Derivatives of 5-heteroarylidene-2,4- thiazolidinediones, fluoroquinolone-thiadiazole hybrids, and others.

CONCLUSION

1,3,4-thiadiazoles and thiazoles are valuable resource for researchers engaged in rational drug design and development in this area.

Exploring potent aldose reductase inhibitors for anti-diabetic (anti-hyperglycemic) therapy: integrating structure-based drug design, and MMGBSA approaches

Aldose reductase (AR) is an important target in the development of therapeutics against hyper-glycemia-induced health complications such as retinopathy, etc. In this study, we employed a combination of structure-based drug design, molecular simulation, and free energy calculation approaches to identify potential hit molecules against anti-diabetic (anti-hyperglycemic)-induced health complications. The 3D structure of aldoreductase was screened for multiple compound libraries (1,00,000 compounds) and identified as ZINC35671852, ZINC78774792 from the ZINC database, Diamino-di nitro-methyl dioctyl phthalate, and Penta-o-galloyl-glucose from the South African natural compounds database, and Bisindolylmethane thiosemi-carbazides and Bisindolylme-thane-hydrazone from the Inhouse database for this study. The mode of binding interactions of the selected compounds later predicted their aldose reductase inhibitory potential. These com-pounds interact with the key active site residues through hydrogen bonds, salt bridges, and π-π interactions. The structural dynamics and binding free energy results further revealed that these compounds possess stable dynamics with excellent binding free energy scores. The structures of the lead inhibitors can serve as templates for developing novel inhibitors, and in vitro testing to confirm their anti-diabetic potential is warranted. The current study is the first to design small molecule inhibitors for the aldoreductase protein that can be used in the development of therapeutic agents to treat diabetes.

Novel Quinazolinone Derivatives: Potential Synthetic Analogs for the Treatment of Glaucoma, Alzheimer's Disease and Diabetes Mellitus

Quinazolinones, which represent an important part of nitrogen-containing six-membered heterocyclic compounds, are frequently used in drug design due to their wide biological activity properties. Therefore, the novel quinazolinones were synthesized from the reaction of acylated derivatives of 4-hydroxy benzaldehyde with 3-amino-2-alkylquinazolin-4(3H)-ones with good yields (85-94 %) and their structures were characterized using Fourier-transform Infrared (FT-IR), Nuclear Magnetic Resonance (1 H-NMR, 13 C-NMR), and High-Resolution Mass Spectroscopy (HR-MS). As the application of the synthesized compounds, their inhibition properties of the synthesized compounds on α-Glucosidase (α-Glu), Acetylcholinesterase (AChE), Butyrylcholinesterase (BChE), and Carbonic anhydrase I-II (hCA I-II) metabolic enzymes were investigated. All compounds showed inhibition at nanomolar level with the Ki values in the range of 12.73±1.26-93.42±9.44 nM for AChE, 8.48±0.92-25.84±2.59 nM for BChE, 66.17±5.16-818.06±44.41 for α-Glu, 2.56±0.26-88.23±9.72 nM for hCA I, and 1.68±0.14-85.43±7.41 nM for hCA II. Molecular docking study was performed to understand the interactions of the most potent compounds with corresponding enzymes. Also, absorption, distribution, metabolism, excretion, and toxicity (ADME/T) properties of the compounds were investigated.

Design, synthesis, spectroscopic characterizations, in vitro pancreatic lipase as well as tyrosinase inhibition evaluations and in silico analysis of novel aryl sulfonate-naphthalene hybrids

One of the primary purposes of this study is to synthesize new aryl sulfonate-naphthalene hybrid structures possessing divergent electron-withdrawing and electron-releasing functional groups. Following the improved reaction conditions, we successfully gathered ten distinct sulfonate derivatives (3a-j) with good yields. The synthesized naphthalene-based sulfonate derivatives were then characterized using appropriate analytical methods (FT-IR, 1H-NMR, 13C-NMR, HRMS, and elemental analysis). Additionally, in vitro and in silico enzyme inhibitory properties of the prepared aryl sulfonate-naphthalene hybrid structures were evaluated against pancreatic lipase and tyrosinase enzymes. Corresponding in vitro enzyme activity investigations revealed that the produced compounds inhibit pancreatic lipase and tyrosinase enzymes significantly. According to the lowest IC50 values, 3h (95.3 ± 4.0 µM) demonstrated the most effective inhibition against pancreatic lipase, whereas 3a (40.8 ± 3.3 µM) was found as the most effective inhibition against the tyrosinase. According to in silico studies, 3a exhibited the highest affinity value (-9.9 kcal/mol) against pancreatic lipase, whereas 3f demonstrated the best affinity value (-8.7 kcal/mol) against tyrosinase.Furthermore, we investigated various structural and physicochemical properties of the target molecules, namely frontier orbital' (HOMO, LUMO, and bandgap) energies (including their corresponding contour plots), global reactivity descriptors (ionization energy and electron affinity), and electronegativity values gathered from ground-state (GS) density functional theory (DFT) calculations. These investigations demonstrated that the observed electrostatic interactions effectively contributed to the studied molecules' experimentally demonstrated enzyme inhibition potential. Also, ADMET studies were evaluated to enlighten the molecular interactions of the compounds with the enzymes.Communicated by Ramaswamy H. Sarma.

Synthesis and characterization of novel acyl hydrazones derived from vanillin as potential aldose reductase inhibitors

In the polyol pathway, aldose reductase (AR) catalyzes the formation of sorbitol from glucose. In order to detoxify some dangerous aldehydes, AR is essential. However, due to the effects of the active polyol pathway, AR overexpression in the hyperglycemic state leads to microvascular and macrovascular diabetic problems. As a result, AR inhibition has been recognized as a potential treatment for issues linked to diabetes and has been studied by numerous researchers worldwide. In the present study, a series of acyl hydrazones were obtained from the reaction of vanillin derivatized with acyl groups and phenolic Mannich bases with hydrazides containing pharmacological groups such as morpholine, piperazine, and tetrahydroisoquinoline. The resulting 21 novel acyl hydrazone compounds were investigated as an inhibitor of the AR enzyme. All the novel acyl hydrazones derived from vanillin demonstrated activity in nanomolar levels as AR inhibitors with IC50 and KI values in the range of 94.21 ± 2.33 to 430.00 ± 2.33 nM and 49.22 ± 3.64 to 897.20 ± 43.63 nM, respectively. Compounds 11c and 10b against AR enzyme activity were identified as highly potent inhibitors and showed 17.38 and 10.78-fold more effectiveness than standard drug epalrestat. The synthesized molecules' absorption, distribution, metabolism, and excretion (ADME) effects were also assessed. The probable-binding mechanisms of these inhibitors against AR were investigated using molecular-docking simulations.

Novel acetic acid derivatives containing quinazolin-4(3H)-one ring: Synthesis, in vitro, and in silico evaluation of potent aldose reductase inhibitors

Aldose reductase (AR) is a crucial enzyme of the polyol pathway through which glucose is metabolized under conditions of hyperglycemia related to diabetes. A series of novel acetic acid derivatives containing quinazolin-4(3H)-one ring (1-22) was synthesized and tested for in vitro AR inhibitory effect. All the target compounds exhibited nanomolar activity against the target enzyme, and all compounds displayed higher activity as compared to the reference drug epalrestat. Among them, Compound 19, named 2-(4-[(2-[(4-methylpiperazin-1-yl)methyl]-4-oxoquinazolin-3(4H)-ylimino)methyl]phenoxy)acetic acid, displayed the strongest inhibitory effect with a KI value of 61.20 ± 10.18 nM. Additionally, these compounds were investigated for activity against L929, nontumoral fibroblast cells, and MCF-7, breast cancer cells using the MTT assay. Compounds 16 and 19 showed lower toxicity against the normal L929 cells. The synthesized compounds' (1-22) absorption, distribution, metabolism, and excretion properties were also evaluated. Molecular docking simulations were used to look into the possible binding mechanisms of these inhibitors against AR.

Molecular docking studies, anti-Alzheimer's disease, antidiabetic, and anti-acute myeloid leukemia potentials of narcissoside

In this research, we explored their capacity for Narcissoside antioxidant and anticholinergic, antidiabetic, and anti-acute myeloid leukaemia. Narcissoside's antioxidant activities were elucidated by the use of various bioanalytical assays. Narcissoside's radical scavenging activities were evaluated by DPPH^• and ABTS^•+ scavenging activities. On the other hand, IC₅₀ values were calculated for DPPH^•, and ABTS^•+ scavenging, acetylcholinesterase, and α-glucosidase inhibition effects of narcissoside. IC₅₀ values narcissoside, as 11.54 nM for AChE and 65.58 nM for α-glucosidase were calculated with % Activity-[Inhibitory] graphs. Then, ADME/T analysis of narcissoside molecule was performed to calculate the drug becoming parameters.

Pyrimidines: Molecular docking and inhibition studies on carbonic anhydrase and cholinesterases

Alzheimer's disease (AD) is a neurodegenerative disorder. The disease is characterized by dementia, memory impairment, cognitive impairment, and speech impairment. Cholinesterases (ChEs; AChE, acetylcholinesterase and BChE, butyrylcholinesterase) inhibitors and their benefits of cholinergic replacement in the treatment of AD have been researched and documented by scientists in various ways to date. Recent studies prove that human carbonic anhydrases (hCAs) are also one of the important targets in the treatment of AD. Therefore, the development of new agents that can simultaneously modulate the various mechanisms or targets involved in the AD pathway may be a powerful strategy to treat AD, the current disease. Considering these data, the effects of the pyrimidines (1-7) were investigated in this study for the discovery and development of multitargeted ChEs and hCAs inhibitors associated with AD. In addition, the molecular docking analysis of the 4-amino-2-choloropyrimidine (2) was performed to understand the binding interactions on the active site of the enzyme. All compounds (1-7) showed satisfactory enzyme inhibitory potency in micromolar concentrations against AChE, BChE, hCAI, and hCAII with K_I values ranging from 0.099 to 0.241 μM, from 1.324 to 3.418 μM, from 0.201 to 0.884 μM, from 1.867 to 3.913 μM, respectively. Due to their ChEs and hCAs inhibition, these compounds (1-7) may be considered as leads for investigations in neurodegenerative diseases. All these results revealed that the 4-amino-5,6-dichloropyrimidine (7) (K_I value of 0.201 ± 0.041 μM for hCA I), the 4-amino-6-hydroxypyrimidine (4) (K_I value of 1.867 ± 0.296 μM for hCA II), the 4-amino-5,6-dichloropyrimidine (7) (K_I value of 0.099 ± 0.008 μM for AChE), and the 4-amino-2-chloropyrimidine (2) (K_I value of 1.324 ± 0.273 μM for BChE) from the pyrimidines in this series were the most promising derivatives, as they exhibited a good multifunctional inhibition at all experimental levels and in the in silico validation against these enzymes, for the treatment of AD.

Recombinant human carbonic anhydrase VII: Purification, characterization, inhibition, and molecular docking studies

Human carbonic anhydrase VII (hCA VII), a cytosolic enzyme, defends against oxidative stress by preventing reactive oxygen species from forming. In our study, first, hCA VII was cloned into Escherichia coli (One Shot Mach1-T1R) strain by using cDNA of the human brain and successfully expressed. The integrity of the plasmid generated by colony PCR was checked, and after, for protein expression, the plasmid was transformed into E. coli BL21 (DE-3) strain. hCA VII expression was observed after 6 h of isopropyl-D-1-thiogalactopyranoside (IPTG) induction. The fusion protein containing hexahistidine (6xHis) was purified with 7.02 EU/mg of specific activity, had 48.07% of purification yield, and approximately 21-folds using a ProbondTM nickel chelating resin affinity column. Then, both molecular mass determination and purity control of the purified recombinant enzyme was done by SDS-PAGE (sodium dodecyl sulfate-polyacrylamide gel electrophoresis). The mass of the SUMO-hCA VII fusion protein was calculated as 46.77 kDa. As a result of Western blot analysis using anti-His G-HRP antibody, the fusion protein was detected as approximately 45 kDa. Furthermore, the characterization assays and in vitro inhibition studies were done for the recombinant enzyme. K_I values of these agents were found between 0.29 μM and 157.6 mM. Finally, molecular docking investigations of these antibiotics were undertaken to understand further the binding interactions on the active site of this recombinant enzyme.

Synthesis and evaluation of novel xanthene-based thiazoles as potential antidiabetic agents

A series of xanthene-based thiazoles was synthesized and characterized by different scpectroscopic methods, i.e. Proton nuclear magnetic resonance (¹ H NMR), carbon nuclear magnetic resonance (¹³ C NMR), infrared spectroscopy, carbon hydrogen nitrogen analysis, and X-ray crystallography. The inhibition potencies of 18 newly synthesized thiazole derivatives were investigated on the activities of acetylcholinesterase (AChE), butyrylcholinesterase (BChE), α-amylase (α-Amy), and α-glycosidase (α-Gly) enzymes in accordance with their antidiabetic and anticholinesterase ability. The synthesized compounds have the highest inhibition potential against the enzymes at low nanomolar concentrations. Among the 18 newly synthesized molecules, 3b and 3p were superior to the known commercial inhibitors of the enzymes and have a much more effective inhibitory potential, with IC₅₀ : 2.37 and 1.07 nM for AChE, 0.98 and 0.59 nM for BChE, 56.47 and 61.34 nM for α-Gly, and 152.48 and 124.84 nM for α-Amy, respectively. Finally, the optimized 18 compounds were subjected to molecular docking to describe the interaction between thiazole derivatives and AChE, BChE, α-Amy, and α-Gly enzymes in which important interactions were monitored with amino acid residues of each target enzyme.

Molecular Docking Studies and the Effect of Fluorophenylthiourea Derivatives on Glutathione-Dependent Enzymes

Cancer is a serious problem affecting the health of all human societies. Chemotherapy refers to the use of drugs to kill cancer or the origin of cancer. In the past three decades, researchers have studied about proteins and their roles in the production of cancer cells. Glutathione S-transferases (GSTs) are a superfamily of enzymes that play a key role in cellular detoxification, protecting against reactive electrophiles attacks, including chemotherapeutic agents. Glutathione reductase (GR) is an important antioxidant enzyme involved in protecting the cell against oxidative stress. In this current study, GST and GR enzymes were purified from human erythrocytes using affinity chromatography. GR was obtained with a specific activity of 5.95 EU/mg protein and a 52.38 % yield. GST was obtained with a specific activity of 4.88 EU/mg protein and a 74.88 % yield. The effect of fluorophenylthiourea derivatives on the purified enzymes was investigated. Afterward, K_I values were found to range from 23.04±4.37 μM-59.97±13.45 μM for GR and 7.22±1.64 μM-41.24±2.55 μM for GST. 1-(2,6-difluorophenyl)thiourea was showed the best inhibition effect for both GST and GR enzymes. The relationships of inhibitors with 3D structures of GST and GR were explained by molecular docking studies.

CADD Studies in the Discovery of Potential ARI (Aldose Reductase Inhibitors) Agents for the Treatment of Diabetic Complications

The lack of currently available drugs for treating diabetes complications has stimulated our interest in finding new Aldose Reductase inhibitors (ARIs) with more beneficial biological properties. One metabolic method uses aldose reductase inhibitors in the first step of the polyol pathway to control excess glucose flux in diabetic tissues. Computer-aided drug discovery (CADD) is key in finding and optimizing potential lead substances. AR inhibitors (ARI) have been widely discussed in the literature. For example, Epalrestat is currently the only ARI used to treat patients with diabetic neuropathy in Japan, India, and China. Inhibiting R in patients with severe to moderate diabetic autonomic neuropathy benefits heart rate variability. AT-001, an AR inhibitor, is now being tested in COVID-19 to see how safe and effective it reduces inflammation and cardiac damage. In summary, these results from animal and human studies strongly indicate that AR can cause cardiovascular complications in diabetes. The current multi-center, large-scale randomized human study of the newly developed powerful ARI may prove its role in diabetic cardiovascular disease to establish therapeutic potential. During the recent coronavirus disease (COVID-19) outbreak in 2019, diabetes and cardiovascular disease were risk factors for severely negative clinical outcomes in patients with COVID19. New data shows that diabetes and obesity are among the strongest predictors of COVID-19 hospitalization. Patients and risk factors for severe morbidity and mortality of COVID- 19.

Enzyme inhibition, molecular docking, and density functional theory studies of new thiosemicarbazones incorporating the 4-hydroxy-3,5-dimethoxy benzaldehyde motif

New Schiff base-bearing thiosemicarbazones (1-13) were obtained from 4-hydroxy-3,5-dimethoxy benzaldehyde and various isocyanates. The structures of the synthesized molecules were elucidated in detail. Density functional theory calculations were also performed to determine the spectroscopic properties of the compounds. Moreover, the enzyme inhibition activities of these compounds were investigated. They showed highly potent inhibition effects on acetylcholinesterase (AChE) and human carbonic anhydrases (hCAs) (K_I values are in the range of 51.11 ± 6.01 to 278.10 ± 40.55 nM, 60.32 ± 9.78 to 300.00 ± 77.41 nM, and 64.21 ± 9.99 to 307.70 ± 61.35 nM for AChE, hCA I, and hCA II, respectively). In addition, molecular docking studies were performed, confirmed by binding affinities studies of the most potent derivatives.

Molecular docking and inhibition studies of vulpinic, carnosic and usnic acids on polyol pathway enzymes

Aldose reductase (AR) and sorbitol dehydrogenase (SDH) are important enzymes of the polyol pathway. In the current study, inhibitory effects of vulpinic acid (VA) carnosic acid (CA) and usnic acid (UA) on purified AR and SDH enzymes were determined. These enzymes inhibition could be essential to prevent diabetic complications. AR and SDH enzymes were purified from sheep kidney. Then, VA, CA and UA were tested in various concentrations against these enzymes activity in vitro. K_I values were found to be as 1.46 ± 0.04, 5.13 ± 0.25 and 11.71 ± 0.27 μΜ for VA, CA and UA, respectively, for AR. K_I constants were found to be as 15.32 ± 0.34, 145.60 ± 2.17 and 213.40 ± 2.64 μΜ VA, CA and UA, respectively, for SDH. These findings indicate that VA, CA and UA could be useful in the treatment of diabetic complications.Communicated by Ramaswamy H. Sarma.

Benzimidazolium Salts Containing Trifluoromethoxybenzyl: Synthesis, Characterization, Crystal Structure, Molecular Docking Studies and Enzymes Inhibitory Properties

The method for producing 4-trifluoromethoxybenzyl substituted benzimidazolium salts is described in this article. The method is based on the reaction of 4-trifluoromethoxybenzyl substituent alkylating agent with 1-alkylbenzimidazole. This method yielded 1-(4-trifluoromethoxybenzyl)-3-alkylbenzimidazolium bromide salts. These benzimidazolium salts were characterized by using ¹ H-NMR, ¹³ C-NMR, FT-IR spectroscopy, and elemental analysis techniques. The crystal structure of 1f was enlightened by single crystal X-ray diffraction studies. Also, the enzyme inhibition effects of the synthesised compounds were investigated. They demonstrated highly potent inhibition effect on acetylcholinesterase (AChE) and carbonic anhydrases (hCAs) (K_i values are in the range of 7.24±0.99 to 39.12±5.66 nM, 5.57±0.96 to 43.07±11.76 nM, and 4.38±0.43 to 18.68±3.60 nM for AChE, hCA I, and hCA II, respectively). In molecular docking study, the interactions of active compounds showing activity against AChE and hCAs enzymes were examined. The most active compound 1f has -10.90 kcal/mol binding energy value against AChE enzyme, and the potential structure compound 1e, which has activity against hCA I and hCA II enzymes, was -7.51 and -8.93 kcal/mol, respectively.

Screening of in vitro and in silico effect of Fluorophenylthiourea compounds on glucose 6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase enzymes

Inhibition studies of enzymes in the pentose phosphate pathway (PPP) have recently emerged as a promising technique for pharmacological intervention in several illnesses. Glucose 6-phosphate dehydrogenase (G6PD) and 6-phosphogluconate dehydrogenase (6PGD) are the most important enzymes of the PPP. For this purpose, in the current study, we examined the effect of some fluorophenylthiourea on G6PD and 6PGD enzyme activity. These compounds exhibited moderate inhibitory activity against G6PD and 6PGD with K_I values ranging from 21.60 ± 8.42 to 39.70 ± 11.26 μM, and 15.82 ± 1.54 to 29.97 ± 5.72 μM, respectively. 2,6-difluorophenylthiourea displayed the most potent inhibitory effect for G6PD, and 2-fluorophenylthiourea demonstrated the most substantial inhibitory effect for 6PGD. Furthermore, the molecular docking analyses of the fluorophenylthioureas, competitive inhibitors, were performed to understand the binding interactions at the enzymes' binding site.

Biological evaluation and in silico study of benzohydrazide derivatives as paraoxonase 1 inhibitors

Serum paraoxonase 1 (PON1) is found in all mammalian species and is a calcium-dependent hydrolytic enzyme. PON1 hydrolyze several substrates, including carbonates, esters, and organophosphates. In the current study, we aimed to investigate the effect of the presynthesized benzohydrazide derivatives (1-9) on PON1 activity. Benzohydrazide compounds moderate inhibited PON1 with the half-maximal inhibitory concentration values ranging from 76.04 ± 13.51 to 221.70 ± 13.59 μM and K_I values ranging from 38.75 ± 12.21 to 543.50 ± 69.76 μM. Compound 4 (2-amino-4-chlorobenzohydrazide) showed the best inhibition (K_I  = 38.75 ± 12.21 μM). Molecular docking and ADME-Tox studies of benzohydrazide derivatives were also carried out. In this context, we hope that the results obtained in this study contribute to the determination of the side effects of current and new benzohydrazide-based pharmacological compounds to be developed.

2-amino thiazole derivatives as inhibitors of some metabolic enzymes: An In Vitro and In Silico study

The thiazole derivatives are desirable compounds in the evaluation of their biological activities such as antiprotozoal antibacterial, antifungal, antituberculosis. Considering the medical application potential of 2-amino thiazole compounds, we aimed to determine the effects of 2-amino thiazole derivatives on the activities of carbonic anhydrase I-II isoenzymes, acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). Among the chemicals we used in our study, 2-Amino-4-(4-chlorophenyl)thiazole compound exhibited the best inhibition against hCA I with K_i of 0.008±0.001 μM. The 2-Amino-4-(4-bromophenyl)thiazole compound exhibited the best inhibition against hCA II, AChE and BChE with K_i of 0.124±0.017 μM, 0.129±0.030 μM and 0.083±0.041 μM, respectively. Molecular docking analysis showed that compound 2-Amino-4-(5,6,7,8-tetrahydro-2-naphthyl)thiazole had the highest inhibitory potency against hCA I, hCA II, AChE, BChE with the estimated binding energy of -6.75 , -7.61, -7.86, -7.96 kcal/mol, respectively. This article is protected by copyright. All rights reserved.

Isolation of Some Phenolic Compounds from Plantago subulata L. and Determination of Their Antidiabetic, Anticholinesterase, Antiepileptic and Antioxidant Activity

In the current study, some phenolic compounds, including acteoside, isoacteoside, echinacoside, and arenarioside purified and characterized from Plantago subulata. These compounds were tested for its antioxidant potential, including Fe³⁺ and Cu²⁺ reductive ability and Fe²⁺ chelating effects. The inhibitory effects of isolated phenolic compounds were tested towards human carbonic anhydrase I and II isoenzymes (hCA I and hCA II), butyrylcholinesterase (BChE) acetylcholinesterase (AChE), aldose reductase (AR) and α-glycosidase (α-gly). K_i values were found these compounds in range of 0.24±0.05-1.38±0.34 μM against hCA I, 0.194±0.018-1.03±0.06 μM against hCA II, 0.043±0.01-0.154±0.02 μM against AChE, 3.92±1.08-11.93±4.45 μM against BChE, 0.082±0.0008-1.68±0.42 μM against AR, and 6.93±2.74-17.17±6.70 μM against α-glycosidase. As a result, isolated compounds displayed inhibition effects against studied all metabolic enzymes. They are promising candidates for treating disorders like Alzheimer's disease, diabetes mellitus, glaucoma, leukemia, and epilepsy.

Synthesis, biological evaluation, and in silico study of novel library sulfonates containing quinazolin-4(3H)-one derivatives as potential aldose reductase inhibitors

A series of novel sulfonates containing quinazolin-4(3H)-one ring derivatives was designed to inhibit aldose reductase (ALR2, EC 1.1.1.21). Novel quinazolinone derivatives (1-21) were synthesized from the reaction of sulfonated aldehydes with 3-amino-2-alkylquinazolin-4(3H)-ones in glacial acetic acid with good yields (85%-94%). The structures of the novel molecules were characterized using IR, 1 H-NMR, 13 C-NMR, and HRMS. All the novel quinazolinones (1-21) demonstrated nanomolar levels of inhibitory activity against ALR2 (KI s are in the range of 101.50-2066.00 nM). Besides, 4-[(2-isopropyl-4-oxoquinazolin-3[4H]-ylimino)methyl]phenyl benzenesulfonate (15) showed higher inhibitor activity inhibited ALR2 up to 7.7-fold compared to epalrestat, a standard inhibitor. Binding interactions between ALR2 and quinazolinones have been investigated using Schrödinger Small-Molecule Drug Discovery Suite 2021-1, reported possible inhibitor-ALR2 interactions. Both in vitro and in silico study results suggest that these quinazolin-4(3H)-one ring derivatives (1-21) require further molecular modification to improve their drug nominee potency as an ALR2 inhibitor.

Potential thiosemicarbazone-based enzyme inhibitors: Assessment of antiproliferative activity, metabolic enzyme inhibition properties, and molecular docking calculations

A new series of thiosemicarbazone derivatives (1-11) were prepared from various aldehydes and isocyanates with high yields and practical methods. The structures of these compounds were elucidated by Fourier transform infrared, ¹ H-nuclear magnetic resonance (NMR), ¹³ C-NMR spectroscopic methods and elemental analysis. Cytotoxic effects of target compounds were determined by 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide assay and compound 1 showed significant cytotoxic activity against both MCF-7 and MDA-MB-231 cells, with half-maximal inhibitory concentration values of 2.97 μM and 6.57 μM, respectively. Moreover, in this study, the anticholinergic and antidiabetic potentials of these compounds were investigated. To this aim, the effect of the newly synthesized thiosemicarbazone derivatives on the activities of acetylcholinesterase (AChE) and αglycosidase (α-Gly) was evaluated spectrophotometrically. The title compounds demonstrated high inhibitory activities compared to standard inhibitors with K_i values in the range of 122.15-333.61 nM for α-Gly (K_i value for standard inhibitor = 75.48 nM), 1.93-12.36 nM for AChE (K_i value for standard inhibitor = 17.45 nM). Antiproliferative activity and enzyme inhibition at the molecular level were performed molecular docking studies for thiosemicarbazone derivatives. 1M17, 5FI2, and 4EY6, 4J5T target proteins with protein data bank identification with (1-11) compounds were docked for anticancer and enzyme inhibition, respectively.

New Pd(II) complexes of the bisthiocarbohydrazones derived from isatin and disubstituted salicylaldehydes: Synthesis, characterization, crystal structures and inhibitory properties against some metabolic enzymes

Pd(II) complexes (Pd1, Pd2, and Pd3) were synthesized for the first time using asymmetric isatin bisthiocarbohydrazone ligands and PdCl₂(PPh₃)₂. All complexes were characterized by a range of spectroscopic and analytical techniques. The molecular structures of Pd1 and Pd3 have been determined by single-crystal X-ray diffraction analysis. The complexes are diamagnetic and exhibit square planar geometry. The asymmetric isatin bisthiocarbohydrazone ligands coordinate to Pd(II) ion in a tridentate manner, through the phenolic oxygen, imine nitrogen and thiol sulfur, forming five- and six-membered chelate rings within their structures. The fourth coordination site in these complexes is occupied by PPh₃ (triphenylphosphine). The free ligands and their Pd(II) complexes were evaluated for their carbonic anhydrase I, II (hCAs) and acetylcholinesterase (AChE) inhibitor activities. They showed a highly potent inhibition effect on AChE and hCAs. K_i values are in the range of 9 ± 0.6 - 30 ± 5.4 nM for AChE, 7 ± 0.5 - 16 ± 2.2 nM for hCA I and 3 ± 0.3-24 ± 1.9 nM for hCA II isoenzyme. The results clearly demonstrated that the ligands and their Pd(II) complexes effectively inhibited the used enzymes.

Type 1 Diabetes in Pregnancy: A Review of Complications and Management

BACKGROUND

Pre-gestational diabetes can pose significant risk to the mother and infant, thus requiring careful counselling and management. Since Saint Vincent's declaration in 1989, adverse maternal and fetal outcomes, such as preeclampsia, perinatal mortality, congenital anomalies, and macrosomia, continue to be associated with type 1 diabetes. Although pregnancy is not considered an independent risk factor for the development of new onset microvascular complications, it is known to exacerbate pre-existing microvascular disease. Strict glycaemic control is the optimal management for pre-existing type 1 diabetes in pregnancy, as raised HbA1C is associated with increased risk of maternal and fetal complications. More recently, time in range on Continuous Glucose Monitoring glucose profiles has emerged as another useful evidence-based marker of fetal outcomes.

OBJECTIVES

This review summarises the complications associated with pre-gestational type 1 diabetes, appropriate evidence-based management, including preparing for pregnancy, intrapartum and postpartum care.

METHODS

A structured search of the PubMed and Cochrane databases was conducted. Peer-reviewed articles about complications and management guidelines on pre-gestational type 1 diabetes were selected and critically appraised.

RESULTS

One hundred and twenty-three manuscripts were referenced and appraised in this review, and international guidelines were summarised.

CONCLUSION

This review provides a comprehensive overview of the recurring themes in the literature pertaining to type 1 diabetes in pregnancy: maternal and fetal complications, microvascular disease progression, and an overview of current guideline-specific management.

Potential Molecular Mechanism of Yishen Capsule in the Treatment of Diabetic Nephropathy Based on Network Pharmacology and Molecular Docking

PURPOSE

Using network pharmacology and molecular docking to explore the mechanism of Yishen Capsule in the treatment of diabetic nephropathy.

MATERIALS AND METHODS

Active components of Yishen Capsule were obtained using database such as TCMSP and TCMID. UniProt protein database was used to screen and standardize the human-derived targets of the active chemical components. Diabetic nephropathy (DN) targets were obtained from databases such as GeneCards, OMIM, TTD, DisGeNET and DrugBank. A network of "Yishen Capsule Components-diabetic nephropathy Targets-Pathways" was constructed by analyzing data above to screening out core targets for molecular docking verification. DN is induced by streptozocin in rats after left nephrectomy. Renal tubular epithelial cells (RTECs) was isolated  and cultured under high glucose conditions. Based on these experimental models, key pathway target genes screened by network pharmacology were verified both in vitro and in vivo.

RESULTS

The main active components of Yishen Capsule in the treatment of DN include quercetin, kaempferol, gallic acid, astragaloside IV, etc. Some key targets (such as AR, AKT1, TP53, ESR1, JUN) and important signal pathways (such as AGE-RAGE, HIF-1 and JAK-STAT signal pathway) were included in the treatment of DN with Yishen Capsule. Molecular docking assay showed that most of the targets have good binding activity with the components of Yishen Capsule. Based on the results of network pharmacology, key target proteins in HIF-1α and JAK2/STAT3 signaling pathways were selected for experimental verification. Results presented that HIF-1α, JAK2, STAT3, TGF-β and MCP-1 were increased under high glucose environment. With the treatment of Yishen Capsule, the expression of HIF-1α further increased, while the expression of JAK2, STAT3, MCP-1 and TGF-β was decreased.

CONCLUSION

This study revealed the mechanism of Yishen Capsule in the treatment of DN, which possesses the characteristics of multi-component, multi-target, and multi-pathway. Further experiments confirmed that Yishen Capsule interfered with HIF-1α and JAK/STAT signaling pathways to reduce inflammation and fibrosis damage in the kidney tissue of rats with diabetic nephropathy.

Novel amino acid Schiff base Zn(II) complexes as new therapeutic approaches in diabetes and Alzheimer's disease: Synthesis, characterization, biological evaluation, and molecular docking studies

Schiff bases are compounds that have gained importance in the paint industry due to their colorful nature and in the field of chemistry and biochemistry due to their biological activities. Various biological applications of Schiff bases, such as antitumor, antifungal, antibacterial, antioxidant, antituberculosis, and anthelmintic, have been widely studied. Within the scope of the study, 5-bromo-2-hydroxybenzaldehyde and amino acid methyl esters (isoleucine, phenylalanine, and methionine) and amino acid Schiff bases were synthesized first. The synthesis of the new Zn(II) complexes of these Schiff bases was carried out by the reaction of synthesized Schiff bases and Zn(OAc)₂ ·2H₂ O. The structures of the synthesized complexes were elucidated using elemental analysis, Fourier transform infrared, nuclear magnetic resonance, UV-visible, and thermal analysis spectroscopy techniques. These synthesized salts were found to be effective inhibitor compounds for the α-glycosidase, and acetylcholinesterase enzyme with Ki values in the range of 30.50 ± 3.82-38.17 ± 6.26 µM for α-glycosidase, 3.68 ± 0.54-10.27 ± 1.68 µM for butyrylcholinesterase, and 6.26 ± 0.83-15.73 ± 4.73 µM for acetylcholinesterase, respectively.

Biological effects of bis-hydrazone compounds bearing isovanillin moiety on the aldose reductase

Aldose reductase (ALR2), one of the metabolically important enzymes, catalyzes the formation of sorbitol from glucose in the polyol pathway. ALR2 inhibition is required to prevent diabetic complications. In the present study, the novel bis-hydrazone compounds bearing isovanillin moiety (GY1-12) were synthesized, and various chromatographic methods were applied to purify the ALR2 enzyme. Afterward, the inhibitory effect of the synthesized compounds on the ALR2 was screened in vitro. All the novel bis-hydrazones demonstrated activity in nanomolar levels as AR inhibitors with IC₅₀ and K_I values in the range of 12.55-35.04 nM, and 13.38-88.21 nM, respectively. Compounds GY-11, GY-7, and GY-5 against ALR2 were identified as the highly potent inhibitors, respectively, and were superior to the standard drug, epalrestat. Moreover, a comprehensive ligand-receptor interactions prediction was performed using ADME-Tox, Glide XP, and MM-GBSA modules of Schrödinger Small-Molecule Drug Discovery Suite to elucidate the novel bis-hydrazone derivatives, potential binding modes versus the ALR2. As a result, these compounds with ALR2 inhibitory effects may be potential alternative agents that can be used to treat or prevent diabetic complications.

Physiological and Pathological Roles of Aldose Reductase

Aldose reductase (AR) is an aldo-keto reductase that catalyzes the first step in the polyol pathway which converts glucose to sorbitol. Under normal glucose homeostasis the pathway represents a minor route of glucose metabolism that operates in parallel with glycolysis. However, during hyperglycemia the flux of glucose via the polyol pathway increases significantly, leading to excessive formation of sorbitol. The polyol pathway-driven accumulation of osmotically active sorbitol has been implicated in the development of secondary diabetic complications such as retinopathy, nephropathy, and neuropathy. Based on the notion that inhibition of AR could prevent these complications a range of AR inhibitors have been developed and tested; however, their clinical efficacy has been found to be marginal at best. Moreover, recent work has shown that AR participates in the detoxification of aldehydes that are derived from lipid peroxidation and their glutathione conjugates. Although in some contexts this antioxidant function of AR helps protect against tissue injury and dysfunction, the metabolic transformation of the glutathione conjugates of lipid peroxidation-derived aldehydes could also lead to the generation of reactive metabolites that can stimulate mitogenic or inflammatory signaling events. Thus, inhibition of AR could have both salutary and injurious outcomes. Nevertheless, accumulating evidence suggests that inhibition of AR could modify the effects of cardiovascular disease, asthma, neuropathy, sepsis, and cancer; therefore, additional work is required to selectively target AR inhibitors to specific disease states. Despite past challenges, we opine that a more gainful consideration of therapeutic modulation of AR activity awaits clearer identification of the specific role(s) of the AR enzyme in health and disease.