Exploring Acyl Thiotriazinoindole Based Pharmacophores: Design, Synthesis, and SAR Studies with Molecular Docking and Biological Activity Profiling against Urease, α-amylase, α-glucosidase, Antimicrobial, and Antioxidant Targets.

A diminutive chemical library of acyl thiotriazinoindole (ATTI) based bioactive scaffolds was synthesized, instigated by taking the economical starting material Isatin, through a series of five steps. Isatin was first nitrated followed by the attachment of pentyl moiety via nucleophilic substitution reaction. The obtained compound was reacted with thiosemicarbazide to obtain thiosemicarbazone derivative, which was eventually cyclized using basic conditions in water as solvent. Finally, the reported series was obtained through reaction of nitrated thiotriazinoindole moiety with differently substituted phenacyl bromides. The synthesized compounds were characterized using NMR spectroscopy and elemental analysis. Finally, the synthesized motifs were scrutinized for their potential to impede urease, α-glucosidase, DPPH, and α-amylase. Compound 5 h with para cyano group manifested the most pivotal biological activity among all, displaying IC50 values of 29.7 ± 0.8, 20.5 ± 0.5 and 36.8 ± 3.9 µM against urease, α-glucosidase, and DPPH assay, respectively. Simultaneously, for α-amylase compound 5 g possessing a p-CH3 at phenyl ring unfolded as most active, with calculated IC50 values 90.3 ± 1.1 µM. The scaffolds were additionally gauged for their antifungal and antibacterial activity. Among the tested strains, 5d having bromo as substituent exhibited the most potent antibacterial activity, while it also demonstrated the highest potency against Aspergillus fumigatus. Other derivatives 5b, 5e, 5i, and 5j also exhibited dual inhibition against both antibacterial and antifungal strains. The interaction pattern of derivatives clearly displayed their SAR, and their docking scores were correlated with their IC50 values. In molecular docking studies, the importance of interactions like hydrogen bonding was further asserted. The electronic factors of various substituents engendered variety of interactions between the ligands and targets implying their importance in the structures of the synthesized heterocyclic scaffolds. To conclude, the synthesized compounds had satisfactory biological activity against various important targets. Further studies are therefore encouraged by attachment of different substitutions in the structure at various positions to enhance the activity of these compounds.

2ß-Acetoxyferruginol derivatives as α-glucosidase inhibitors: Synthesis and biological evaluation.

To find potential α-glucosidase inhibitors, a series of 2ß-acetoxyferuginol derivatives containing cinnamic acid (WXC-1 âˆ¼ 25) were synthesized and investigated their biological activity. All derivatives (WXC-1 âˆ¼ 25) displayed better inhibitory activity (IC50 values: 7.56 ± 1.35 âˆ¼ 25.63 ± 1.72 µM) compared to acarbose (IC50 vaule: 564.28 ± 48.68 µM). In particularly, WXC-25 with 4-hydroxycinnamic acid section showed the best inhibitory activity (IC50 vaule: 2.02 ± 0.14 µM), ∼75-fold stronger than acarbose. Kinetics results suggested WXC-25 being one reversible non-competition inhibitors. Fluorescence quenching results indicated that WXC-25 quenched the fluorescence of α-glucosidase in a static manner. 3D fluorescence spectra results indicated that WXC-25 treatment could cause the conformation changes of α-glucosidase. Moreover, molecular docking simulated the detailed interaction of WXC25 with α-glucosidase.

Synthesis of Novel Soritin Sulfonamide Derivatives as Potential α-Glucosidase Inhibitor and Their Molecular Docking Studies.

Diabetes Mellitus (DM) is linked to various factors causing cardiovascular diseases, with uncontrolled postprandial hyperglycemia being a direct contributor. α-Glucosidase inhibitors (AGIs) aid in reducing postprandial hyperglycemia, potentially mitigating cardiovascular risks. In order to synthesize novel chemical scaffolds with possible α-glucosidase inhibition activity, a series of novel soritin sulfonamide derivatives were synthesized. The soritin hydrazide was treated with various aryl sulfonyl chlorides to obtain targeted compounds (1-16). Findings suggested that all compounds have better α-glucosidase inhibition compared to standard drugs, acarbose (2187.00 ± 1.25 µM) and 1-deoxynojirimycin (334.90 ± 1.10 µM), with IC50 values ranging from 3.81 ± 1.67 µM to 265.40 ± 1.58 µM. The most potent analog was Compound 13, a trichloro phenyl substituted compound, with IC50 value of 3.81 ± 1.67 µM. Structure-activity relationship (SAR) showed that introducing an additional chlorine group into the parent nucleus increases the potency. The docking studies validated that Compound 13 established hydrogen bonds with the active site residues Asp214, Glu276, and Asp349, while being further stabilized by hydrophobic interactions, providing an explanation for its high potency.

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.

A small, focused library comprising 8 novel compounds was synthesised using a series of substituted quinoxaline sulfonohydrazide derivatives.All synthesised compounds were tested against phospholipase A2 (sPLA2) and α-glucosidase enzymes.The compounds exhibited activities against α-glucosidase and were potent at nanomolar concentrations against sPLA2 isozymes.Structure-based molecular modelling was employed to rationalise the SAR of the compounds.

Discovery of novel thiazole derivatives containing pyrazole scaffold as PPAR-γ Agonists, α-Glucosidase, α-Amylase and COX-2 inhibitors; Design, synthesis and in silico study.

A novel series of thiazole derivatives with pyrazole scaffold 16a-l as hybrid rosiglitazone/celecoxib analogs was designed, synthesized and tested for its PPAR-γ activation, α-glucosidase, α-amylase and COX-2 inhibitory activities. Regarding the anti-diabetic activity, all compounds were assessed in vitro against PPAR-γ activation, α-glucosidase and α-amylase inhibition in addition to in vivo hypoglycemic activity (one day and 15 days studies). Compounds 16b, 16c, 16e and 16 k showed good PPAR-γ activation (activation % ≈ 72-79 %) compared to that of the reference drug rosiglitazone (74 %). In addition, the same derivatives 16b, 16c, 16e and 16 k showed the highest inhibitory activities against α-glucosidase (IC50 = 0.158, 0.314, 0.305, 0.128 µM, respectively) and against α-amylase (IC50 = 32.46, 23.21, 7.74, 35.85 µM, respectively) compared to the reference drug acarbose (IC50 = 0.161 and 31.46 µM for α-glucosidase and α-amylase, respectively). The most active derivatives 16b, 16c, 16e and 16 k also revealed good in vivo hypoglycemic effect comparable to that of rosiglitazone. In addition, compounds 16b and 16c had the best COX-2 selectivity index (S.I. = 18.7, 31.7, respectively) compared to celecoxib (S.I. = 10.3). In vivo anti-inflammatory activity of the target derivatives 16b, 16c, 16e and 16 k supported the results of in vitro screening as the derivatives 16b and 16c (ED50 = 8.2 and 24 mg/kg, respectively) were more potent than celecoxib (ED50 = 30 mg/kg). In silico docking, ADME, toxicity, and molecular dynamic studies were carried out to explain the interactions of the most active anti-diabetic and anti-inflammatory compounds 16b, 16c, 16e and 16 k with the target enzymes in addition to their physiochemical parameters.

Design of new α-glucosidase inhibitors based on the bis-4-hydroxycoumarin skeleton: Synthesis, evaluation, and in silico studies.

In this work, we have reported the design, synthesis, in vitro, and in silico enzymatic evaluation of new bis-4-hydroxycoumarin-based phenoxy-1,2,3-triazole-N-phenylacetamide derivatives 5a-m as potent α-glucosidase inhibitors. All the synthesized analogues showed high inhibition effects against α-glucosidase (IC50 values ranging between 6.0 ± 0.2 and 85.4 ± 2.3 µM) as compared to the positive control acarbose (IC50 = 750.0 ± 0.6 µM). Among the newly synthesized compounds 5a-m, 2,4-dichloro-N-phenylacetamide derivative 5i with inhibition effect around 125-folds more than the acarbose was identified as the most potent entry. A structure-activity relationship (SAR) study about the title compounds 5a-m demonstrated that the inhibition effects of these compounds depend on the pattern of substitution on the N-phenylacetamide ring. The interaction modes and binding energies in the active site of enzyme of the important analogues (in term of SAR study) were evaluated through molecular docking study. Molecular dynamics and prediction of pharmacokinetic properties and toxicity of the most potent compound 5i also evaluated and the obtained data was compared with the acarbose.

Synthesis, Computational Study, and In Vitro α-Glucosidase Inhibitory Action of Thiourea Derivatives Based on 3-Aminopyridin-2(1H)-Ones.

Reactions with allyl-, acetyl-, and phenylisothiocyanate have been studied on the basis of 3-amino-4,6-dimethylpyridine-2(1H)-one, 3-amino-4-phenylpyridine-2-one, and 3-amino-4-(thiophene-2-yl)pyridine-2(1H)-one (benzoyl-)isothiocyanates, and the corresponding thioureide derivatives 8-11a-c were obtained. Twelve thiourea derivatives were obtained and studied for their anti-diabetic activity against the enzyme α-glucosidase in comparison with the standard drug acarbose. The comparison drug acarbose inhibits the activity of α-glucosidase at a concentration of 15 mM by 46.1% (IC50 for acarbose is 11.96 mM). According to the results of the conducted studies, it was shown that alkyl and phenyl thiourea derivatives 8,9a-c, in contrast to their acetyl-(benzoyl) derivatives and 10,11a-c, show high antidiabetic activity. Thus, 1-(4,6-dimethyl-2-oxo-1,2-dihydropyridin-3-yl)-3-phenylthiourea 9a has the highest inhibitory activity against the enzyme α-glucosidase, exceeding the activity of the comparison drug acarbose, which inhibits the activity of α-glucosidase by 56.6% at a concentration of 15 mm (IC50 = 9,77 mM). 1-(6-methyl-2-oxo 4-(thiophen-2-yl)-1,2-dihydropyridin-3-yl)-3-phenylthiourea 9c has inhibitory activity against the enzyme α-glucosidase, comparable to the comparison drug acarbose, inhibiting the activity of α-glucosidase at a concentration of 15 mm per 41.2% (IC50 = 12,94 mM). Compounds 8a, 8b, and 9b showed inhibitory activity against the enzyme α-glucosidase, with a lower activity compared to acarbose, inhibiting the activity of α-glucosidase at a concentration of 15 mM by 23.3%, 26.9%, and 35.2%, respectively. The IC50 against α-glucosidase for compounds 8a, 8b, and 9b was found to be 16.64 mM, 19.79 mM, and 21.79 mM, respectively. The other compounds 8c, 10a, 10b, 10c, 11a, 11b, and 11c did not show inhibitory activity against α-glucosidase. Thus, the newly synthesized derivatives of thiourea based on 3-aminopyridine-2(1H)-ones are promising candidates for the further modification and study of their potential anti-diabetic activity. These positive bioanalytical results will stimulate further in-depth studies, including in vivo models.

Design, synthesis and inhibition evaluation of novel chalcone amide α-glucosidase inhibitors.

Aim: The purpose of this study is to design and synthesize a series of novel chalcone amide α-glucosidase (AG) inhibitors (L1-L10) based on virtual screening and molecular dynamics (MD) simulation. Materials & methods: Target compounds (L1-L10) were synthesized from 2-hydroxyacetophenone and methyl 4-formylbenzoate. Results: In vitro activity test shows that most compounds have good AG inhibition. Specially, compound L4 (IC50 = 8.28 ± 0.04 µM) had the best inhibitory activity, superior to positive control acarbose (IC50 = 8.36 ± 0.02 µM). Molecular docking results show that the good potency of L4 maybe attributed to strong interactions between chalcone skeleton and active site, and the torsion of carbon nitrogen bond in amide group. Conclusion: Compound L4 maybe regard as a good anti-Type II diabetes candidate to preform further study.

[Box: see text].

Unveiling anti-diabetic potential of new thiazole-sulfonamide derivatives: Design, synthesis, in vitro bio-evaluation targeting DPP-4, α-glucosidase, and α-amylase with in-silico ADMET and docking simulation.

Diabetes mellitus type 2 (T2DM) can be managed by targeting dipeptidyl peptidase-4 (DPP-4), an enzyme that breaks down and deactivates peptides such as GIP and GLP-1. In this context, a new series of 2-(2-substituted hydrazineyl)thiazole derivatives 4, 5, 6, 8, 10, and 11 conjugated with the 2-hydroxy-5-(pyrrolidin-1-ylsulfonyl)benzylidene fragment were designed and synthesized. The virtual screening of the designed derivatives inside DPP-4 demonstrated good to moderate activity, with binding affinity ranging from -6.86 to -5.36 kcal/mol compared to Sitagliptin (S=-5.58 kcal/mol). These results encourage us to evaluate DPP-4 using in-vitro fluorescence-based assay. The in-vitro results exhibited inhibitory percentage (IP) values ranging from 40.66 to 75.62 % in comparison to Sitagliptin (IP=63.14 %) at 100 µM. Subsequently, the IC50 values were determined, and the 5-aryl thiazole derivatives 10 and 11 revealed strong potent IC50 values 2.75 ± 0.27 and 2.51 ± 0.27 µM, respectively, compared to Sitagliptin (3.32 ± 0.22 µM). The SAR study exhibited the importance of the substituents on the thiazole scaffold, especially with the hydrophobic fragment at C5 of the thiazole, which has a role in the activity. Compounds 10 and 11 were further assessed toward α-glucosidase and α-amylase enzymes and give promising results. Compound 10 showed good activity against α-glucosidase with IC50 value of 3.02 ± 0.23 µM compared to Acarbose 3.05 ± 0.22 µM and (11 = 3.34 ± 0.10 µM). On the other hand, for α-amylase, compound 11 was found to be most effective with IC50 value of 2.91 ± 0.23 µM compared to compound 10 = 3.30 ± 0.16 µM and Acarbose (2.99 ± 0.21 µM) indicating that these derivatives could reduce glucose by more than one target. The most active derivatives 10 and 11 attracted great interest as candidates for oral bioavailability and safe toxicity profiles compared to positive controls. The in-silico docking simulation was performed to understand the binding interactions inside the DPP-4, α-glucosidase, and α-amylase pockets, and it was found to be promising antidiabetic agents through a number of interactions.

Synthesis and In Silico Analysis of New Polyheterocyclic Molecules Derived from [1,4]-Benzoxazin-3-one and Their Inhibitory Effect against Pancreatic α-Amylase and Intestinal α-Glucosidase.

This study focuses on synthesizing a new series of isoxazolinyl-1,2,3-triazolyl-[1,4]-benzoxazin-3-one derivatives 5a-5o. The synthesis method involves a double 1,3-dipolar cycloaddition reaction following a "click chemistry" approach, starting from the respective [1,4]-benzoxazin-3-ones. Additionally, the study aims to evaluate the antidiabetic potential of these newly synthesized compounds through in silico methods. This synthesis approach allows for the combination of three heterocyclic components: [1,4]-benzoxazin-3-one, 1,2,3-triazole, and isoxazoline, known for their diverse biological activities. The synthesis procedure involved a two-step process. Firstly, a 1,3-dipolar cycloaddition reaction was performed involving the propargylic moiety linked to the [1,4]-benzoxazin-3-one and the allylic azide. Secondly, a second cycloaddition reaction was conducted using the product from the first step, containing the allylic part and an oxime. The synthesized compounds were thoroughly characterized using spectroscopic methods, including 1H NMR, 13C NMR, DEPT-135, and IR. This molecular docking method revealed a promising antidiabetic potential of the synthesized compounds, particularly against two key diabetes-related enzymes: pancreatic α-amylase, with the two synthetic molecules 5a and 5o showing the highest affinity values of 9.2 and 9.1 kcal/mol, respectively, and intestinal α-glucosidase, with the two synthetic molecules 5n and 5e showing the highest affinity values of -9.9 and -9.6 kcal/mol, respectively. Indeed, the synthesized compounds have shown significant potential as antidiabetic agents, as indicated by molecular docking studies against the enzymes α-amylase and α-glucosidase. Additionally, ADME analyses have revealed that all the synthetic compounds examined in our study demonstrate high intestinal absorption, meet Lipinski's criteria, and fall within the required range for oral bioavailability, indicating their potential suitability for oral drug development.

Synthesis, α-glucosidase inhibitory activity, and molecular dynamic simulation of 6-chloro-2-methoxyacridine linked to triazole derivatives.

Α-glucosidase inhibition can be useful in the management of carbohydrate-related diseases, especially type 2 diabetes mellitus. Therefore, in this study, a new series of 6-chloro-2-methoxyacridine bearing different aryl triazole derivatives were designed, synthesized, and evaluated as potent α-glucosidase inhibitors. The most potent derivative in this group was 7h bearing para-fluorine with IC50 values of 98.0 ± 0.3 µM compared with standard drug acarbose (IC50 value = 750.0 ± 10.5 µM). A kinetic study of compound 7h revealed that it is a competitive inhibitor against α-glucosidase. Molecular dynamic simulations of the most potent derivative were also executed and indicated suitable interactions with residues of the enzyme which rationalized the in vitro results.

Design, synthesis, in vitro, and in silico anti-α-glucosidase assays of N-phenylacetamide-1,2,3-triazole-indole-2-carboxamide derivatives as new anti-diabetic agents.

In this work, a novel series of N-phenylacetamide-1,2,3-triazole-indole-2-carboxamide derivatives 5a-n were designed by consideration of the potent α-glucosidase inhibitors containing indole and carboxamide-1,2,3-triazole-N-phenylacetamide moieties. These compounds were synthesized by click reaction and evaluated against yeast α-glucosidase. All the newly title compounds demonstrated superior potency when compared with acarbose as a standard inhibitor. Particularly, compound 5k possessed the best inhibitory activity against α-glucosidase with around a 28-fold improvement in the inhibition effect in comparison standard inhibitor. This compound showed a competitive type of inhibition in the kinetics. The molecular docking and dynamics demonstrated that compound 5k with a favorable binding energy well occupied the active site of α-glucosidase.

α-Glucosidase inhibition assay of galbanic acid and it amide derivatives: New excellent semi-synthetic α-glucosidase inhibitors.

α-Glucosidase inhibitory activity of galbanic acid and its new amide derivatives 3a-n were investigated. Galbanic acid and compounds 3a-n showed excellent anti-α-glucosidase activity with IC50 values ranging from 0.3 ± 0.3 µM to 416.0 ± 0.2 µM in comparison to positive control acarbose with IC50 value of = 750.0 ± 5.6. In the kinetic study, the most potent compound 3h demonstrated a competitive mode of inhibition with Ki = 0.57 µM. The interaction of the most potent compound 3h with the α-glucosidase was further elaborated by in vitro Circular dichroism assessment and in silico molecular docking and Molecular dynamics studies. Compound 3h was also non-cytotoxic on human normal cells. In silico study on pharmacokinetics and toxicity profile of the most potent galbanic acid derivatives demonstrated that these compounds are valuable lead compounds for further study in order to achieve new anti-diabetic agents.

Facile benzothiazole-triazole based thiazole derivatives as novel thymidine phosphorylase and α-glucosidase inhibitors: Experimental and computational approaches.

The present study reports the new thiazole (A-L) derivatives based on benzothiazole fused triazole which were synthesized and assessed against thymidine phosphorylase and α-glucosidase enzymes. Several compounds with the same basic structure but different substituents were found to have high activity against the targeted enzymes, while others with the same basic skeleton but different substituents were found to have medium to low activity among the members of tested series. These analogs showed a varied range of inhibition in both case thymidine phosphorylase and alpha glucosidase, A (IC50 = 7.20 ± 0.30 µM and IC50 = 1.30 ± 0.70 µM), B (IC50 = 8.80 ± 0.10 µM and IC50 = 2.10 ± 0.30 µM), C (IC50 = 8.90 ± 0.40 µM and IC50 = 3.20 ± 0.20 µM) and thiazole containing analogs such as G (IC50 = 11.10 ± 0.20 µM and IC50 = 7.80 ± 0.20 µM) and H (IC50 = 12.30 ± 0.30 µM and IC50 = 6.30 ± 0.20 µM). When compared with standard drugs 7-Deazaxanthine, 7DX (IC50 = 10.60 ± 0.50 µM) and acarbose (IC50 = 4.30 ± 0.30 µM) respectively. These analogs were also subjected to molecular docking studies which indicated the binding interaction of molecules with active sites of the enzyme and strengthen the drug profile of these compounds. ADMET studies also predict the drug-like properties of these compounds, with no violations of drug likeness rules.

Novel thiosemicarbazide-based ß-carboline derivatives as α-glucosidase inhibitors: Synthesis and biological evaluation.

In the quest for potent α-glucosidase inhibitors to combat diabetes, a series of novel thiosemicarbazide-based ß-carboline derivatives (CTL1∼36) were synthesized and evaluated. CTL1∼36 exhibited remarkable inhibitory effects against α-glucosidase, with IC50 values ranging from 2.81 to 12.40 µM, significantly surpassing the positive control acarbose (IC50 = 564.28 µM). Notably, CTL26 demonstrated the most potent inhibition (IC50 = 2.81 µM) and was characterized as a non-competitive inhibitor. Through a combination assay with fluorescence quenching, 3D fluorescence spectra, CD spectra, and molecular docking, we elucidated that CTL26 formed a complex with α-glucosidase via hydrogen bondings and hydrophobic interactions, leading to α-glucosidase conformation changes that impaired enzymatic activity. In vivo studies revealed that oral administration of CTL26 (25 and 50 mg/kg/d) reduced fasting blood glucose levels, enhanced glucose tolerance, and ameliorated lipid abnormalities in diabetic mice. These findings positioned CTL26 as a promising candidate for the development of α-glucosidase inhibitors with anti-diabetic potential.

Discovery of new anti-diabetic potential agents based on paracetamol incorporating sulfa-drugs: Design, synthesis, α-amylase, and α-glucosidase inhibitors with molecular docking simulation.

Uncontrolled diabetes can lead to hyperglycemia, which causes neuropathy, heart attacks, retinopathy, and nervous system damage over time, therefore, controlling hyperglycemia using potential drug target inhibitors is a promising strategy. This work focused on synthesizing new derivatives via the diazo group, using a hybridization strategy involving two approved drugs, paracetamol and several sulfonamides. The newly designed diazo-paracetamols 5-12 were fully characterized and then screened for in vitro α-amylase and α-glucosidase activities and exhibited inhibitory percentages (IP) = 92.5-96.5 % and 91.0-95.7 % compared to Acarbose IP = 96.5 and 95.8 %, respectively at 100 µg/mL. The IC50 values of the synthesized derivatives were evaluated against α-amylase and α-glucosidase enzymes, and the results demonstrated moderate to potent activity. Among the tested diazo-paracetamols, compound 11 was found to have the highest potency activity against α-amylase with IC50 value of 0.98 ± 0.015 µM compared to Acarbose IC50 = 0.43 ± 0.009 µM, followed by compound 10 (IC50 = 1.55 ± 0.022 µM) and compound 9 (IC50 = 1.59 ± 0.023 µM). On the other hand, for α-glucosidase, compound 10 with pyrimidine moiety demonstrated the highest inhibitory activity with IC50 = 1.39 ± 0.021 µM relative to Acarbose IC50 = 1.24 ± 0.029 µM and the order of the most active derivatives was 10 > 9 (IC50 = 2.95 ± 0.046 µM) > 11 (IC50 = 5.13 ± 0.082 µM). SAR analysis confirmed that the presence of 4,5-dimethyl-isoxazole or pyrimidine nucleus attached to the sulfonyl group is important for activity. Finally, the docking simulation was achieved to determine the mode of binding interactions for the most active derivatives in the enzyme's active site.

Design and synthesis of 6-C-alkyl-DMDP type nanomolar inhibitors of ß-galactosidase and ß-glucosidase based on broussonetine S and related derivatives.

Broussonetine S (9), its C-1' and C-10' stereoisomers, and their corresponding enantiomers have been synthesized from enantiomeric arabinose-derived cyclic nitrones, with cross metathesis (CM), epoxidation and Keck asymmetric allylation as key steps. Glycosidase inhibition assays showed that broussonetine S (9) and its C-10' epimer (10'-epi-9) were nanomolar inhibitors of bovine liver ß-galactosidase and ß-glucosidase; while their C-1' stereoisomers were 10-fold less potent towards these enzymes. The glycosidase inhibition results and molecular docking calculations revealed the importance of the configurations of pyrrolidine core and C-1' hydroxyl for inhibition potency and spectra. Together with the docking calculations we previously reported for α-1-C-alkyl-DAB derivatives, we designed and synthesized a series of 6-C-alkyl-DMDP derivatives with very simple alkyl chains. The inhibition potency of these derivatives was enhanced by increasing the length of the side chain, and maintained at nanomolar scale inhibitions of bovine liver ß-glucosidase and ß-galactosidase after the alkyl groups are longer than eight or ten carbons for the (6R)-C-alkyl-DMDP derivatives and their 6S epimers, respectively. Molecular docking calculations indicated that each series of 6-C-alkyl-DMDP derivatives resides in the same active site of ß-glucosidase or ß-galactosidase with basically similar binding conformations, and their C-6 long alkyl chains extend outwards along the hydrophobic groove with similar orientations. The increasing inhibitions of ß-glucosidase and ß-galactosidase with the number of carbon atoms in the side chains may be explained by improved adaptability of longer alkyl chains in the hydrophobic grooves. In addition, the lower ß-glucosidase and ß-galactosidase inhibitions of (6S)-C-alkyl-DMDP derivatives than their C-6 R stereoisomers can be attributed to the misfolding of their alkyl chains and resulted decreased adaptability in the hydrophobic groove. The work reported herein is valuable for design and development of more potent and selective inhibitors of ß-galactosidase and ß-glucosidase, which have potential in treatment of lysosomal storage diseases. Furthermore, part of the 6-C-alkyl-DMDP derivatives and their enantiomers were also tested as potential anti-cancer agents; all the compounds tested were found with moderate cytotoxic effects on MKN45 cells, which would indicate potential applications of these iminosugars in development of novel anticancer agents.

Novel carbazole-oxadiazole derivatives as anti-α-glucosidase and anti-α-amylase agents: Design, synthesis, molecular docking, and biological evaluation.

To find novel inhibitors of α-glucosidase and α-amylase, a series of new carbazole-oxadiazole derivatives (6a-6n) were prepared, and screened for their anti-α-glucosidase and anti-α-amylase effects. Most of the tested derivatives showed different degrees of α-glucosidase and α-amylase inhibitory activity (IC50: 21.39 ± 0.69-92.05 ± 1.54 µM, 45.53 ± 1.50-126.14 ± 6.33 µM, respectively) compared to the standard acarbose (IC50: 427.00 ± 9.56 µM, 24.68 ± 1.10 µM, respectively). Thereinto, 6c (IC50 = 21.39 ± 0.69 µM) displayed the most effective anti-α-glucosidase activity and 6e presented the best anti-α-amylase activity with an IC50 value of 45.53 ± 1.50 µM. Lineweaver-Burk plot analysis suggested that 6c and 6e behaved as mixed α-glucosidase inhibitor and mixed α-amylase inhibitor, respectively. The results of circular dichroism, atomic force microscope, and molecular docking simulation exposed interaction mechanisms between two preferred compounds (6c and 6e) and their corresponding enzymes. Combined with the possible properties of reducing the elevation in postprandial blood glucose, oral activity, positive bioavailability, and low cytotoxicity of 6c and 6e, it could be concluded that the target derivatives may be able to act as lead molecules for the development of new hypoglycemic agents.

In vitro α-glucosidase, docking and density functional theory studies on novel azide metal complexes.

Aim: The goal of this study is to synthesize new metal complexes containing N-methyl-1-(pyridin-2-yl)methanimine and azide ligands as α-glucosidase inhibitors for Type 2 diabetes. Materials & methods: The target complexes (12-16) were synthesized by reacting N-methyl-1-(pyridin-2-yl)methanimine (L1) with sodium azide in the presence of corresponding metal salts. The investigation of target protein interactions, vibrational, electronic and nonlinear optical properties for these complexes was performed by molecular docking and density functional theory studies. Results: Among these complexes, complex 13 (IC50 = 0.2802 ± 0.62 µM) containing Hg ion showed the highest α-glucosidase inhibitory property. On the other hand, significant results were detected for complexes containing Cu and Ag ions. Conclusion: Complex 13 may be an alternate anti-diabetic inhibitor according to in vitro/docking results.

[Box: see text].

Novel acyl hydrazide derivatives of polyhydroquinoline as potent anti-diabetic and anti-glycating agents: Synthesis, in vitro α-amylase, α-glucosidase inhibition and anti-glycating activity with molecular docking insights.

In this study, eleven novel acyl hydrazides derivative of polyhydroquinoline were synthesized, characterized and screened for their in vitro anti-diabetic and anti-glycating activities. Seven compounds 2a, 2d, 2i, 2 h, 2j, 2f, and 2 g exhibited notable α-amylase inhibitory activity having IC50 values from 3.51 ± 2.13 to 11.92 ± 2.30 µM. Similarly, six compounds 2d, 2f, 2 h, 2i, 2j, and 2 g displayed potent α-glucosidase inhibitory activity compared to the standard acarbose. Moreover, eight derivatives 2d, 2 g, 2f, 2j, 2a, 2i, 2 g, and 2e showed excellent anti-glycating activity with IC50 values from 6.91 ± 2.66 to 15.80 ± 1.87 µM when compared them with the standard rutin (IC50 = 22.5 ± 0.90 µM). Molecular docking was carried out to predict the binding modes of all the compounds with α-amylase and α-glucosidase. The docking analysis revealed that most of the compounds established strong interactions with α-amylase and α-glucosidase. All compounds fitted well into the binding pockets of α-amylase and α-glucosidase. Among all compounds 2a and 2f were most potent based on docking score -8.2515 and -7.3949 against α-amylase and α-glucosidase respectively. These results hold promise for the development of novel candidates targeted at controlling postprandial glucose levels in individuals with diabetes.