Aglycone exploration of C-arylglucoside inhibitors of renal sodium-dependent glucose transporter SGLT2

Unveiling Neuroprotective Potential of Spice Plant-Derived Compounds against Alzheimer's Disease: Insights from Computational Studies

Alzheimer's disease (AD) is a serious threat to the global health care system and is brought on by a series of factors that cause neuronal dysfunction and impairment in memory and cognitive decline. This study investigated the therapeutic potential of phytochemicals that belong to the ten regularly used spice plants, based on their binding affinity with AD-associated proteins. Comprehensive docking studies were performed using AutoDock Vina in PyRx followed by molecular dynamic (MD) simulations using AMBER 14. The docking study of the chosen molecules revealed the binding energies of their interactions with the target proteins, while MD simulations were carried out to verify the steadiness of bound complexes. Through the Lipinski filter and admetSAR analysis, the chosen compounds' pharmacokinetic characteristics and drug likeness were also examined. The pharmacophore mapping study was also done and analyzed for best selected molecules. Additionally, principal component analysis (PCA) was used to examine how the general motion of the protein changed. The results showed quercetin and myricetin to be potential inhibitors of AChE and alpha-amyrin and beta-chlorogenin to be potential inhibitors of BuChE, exhibiting best binding energies comparable to those of donepezil, used as a positive control. The multiple descriptors from the simulation study, root mean square deviation (RMSD), root mean square fluctuation (RMSF), hydrogen bond, radius of gyration (Rg), and solvent-accessible surface areas (SASA), confirm the stable nature of the protein-ligand complexes. Molecular mechanic Poisson-Boltzmann surface area (MM-PBSA) binding free energy calculations indicated the energetically favorable binding of the ligands to the protein. Finally, according to pharmacokinetic properties and drug likeness, characteristics showed that quercetin and myricetin for AChE and alpha-amyrin and beta-chlorogenin for BuChE were found to be the most effective agents for treating the AD.

Sodium-Glucose Cotransporter Inhibitors as Antidiabetic Drugs: Current Development and Future Perspectives

Sodium-glucose cotransporter 2 (SGLT-2) inhibitors (gliflozins) represent the most recently approved class of oral antidiabetic drugs. SGLT-2 overexpression in diabetic patients contributes significantly to hyperglycemia and related complications. Therefore, SGLT-2 became a highly interesting therapeutic target, culminating in the approval for clinical use of dapagliflozin and analogues in the past decade. Gliflozins improve glycemic control through a novel insulin-independent mechanism of action and, moreover, exhibit significant cardiorenal protective effects in both diabetic and nondiabetic subjects. Therefore, gliflozins have received increasing attention, prompting extensive structure-activity relationship studies and optimization approaches. The discovery that intestinal SGLT-1 inhibition can provide a novel opportunity to control hyperglycemia, through a multifactorial mechanism, recently encouraged the design of low adsorbable inhibitors selectively directed to the intestinal SGLT-1 subtype as well as of dual SGLT-1/SGLT-2 inhibitors, representing a compelling strategy to identify new antidiabetic drug candidates.

Dual-Target Compounds against Type 2 Diabetes Mellitus: Proof of Concept for Sodium Dependent Glucose Transporter (SGLT) and Glycogen Phosphorylase (GP) Inhibitors

A current trend in the quest for new therapies for complex, multifactorial diseases, such as diabetes mellitus (DM), is to find dual or even multi-target inhibitors. In DM, the sodium dependent glucose cotransporter 2 (SGLT2) in the kidneys and the glycogen phosphorylase (GP) in the liver are validated targets. Several (β-D-glucopyranosylaryl)methyl (het)arene type compounds, called gliflozins, are marketed drugs that target SGLT2. For GP, low nanomolar glucose analogue inhibitors exist. The purpose of this study was to identify dual acting compounds which inhibit both SGLTs and GP. To this end, we have extended the structure-activity relationships of SGLT2 and GP inhibitors to scarcely known (C-β-D-glucopyranosylhetaryl)methyl arene type compounds and studied several (C-β-D-glucopyranosylhetaryl)arene type GP inhibitors against SGLT. New compounds, such as 5-arylmethyl-3-(β-D-glucopyranosyl)-1,2,4-oxadiazoles, 5-arylmethyl-2-(β-D-glucopyranosyl)-1,3,4-oxadiazoles, 4-arylmethyl-2-(β-D-glucopyranosyl)pyrimidines and 4(5)-benzyl-2-(β-D-glucopyranosyl)imidazole were prepared by adapting our previous synthetic methods. None of the studied compounds exhibited cytotoxicity and all of them were assayed for their SGLT1 and 2 inhibitory potentials in a SGLT-overexpressing TSA201 cell system. GP inhibition was also determined by known methods. Several newly synthesized (C-β-D-glucopyranosylhetaryl)methyl arene derivatives had low micromolar SGLT2 inhibitory activity; however, none of these compounds inhibited GP. On the other hand, several (C-β-D-glucopyranosylhetaryl)arene type GP inhibitor compounds with low micromolar efficacy against SGLT2 were identified. The best dual inhibitor, 2-(β-D-glucopyranosyl)-4(5)-(2-naphthyl)-imidazole, had a K_i of 31 nM for GP and IC₅₀ of 3.5 μM for SGLT2. This first example of an SGLT-GP dual inhibitor can prospectively be developed into even more efficient dual-target compounds with potential applications in future antidiabetic therapy.

Crystal structure and Hirshfeld analysis of 3'-bromo-4-methyl-chalcone and 3'-cyano-4-methyl-chalcone

Two crystal structures of chalcones, or 1,3-di-aryl-prop-2-en-1-ones, are presented; both contain a methyl substitution on the 3-Ring, but differ on the 1-Ring, bromo versus cyano. The compounds are 3'-bromo-4-methyl-chalcone [systematic name: 1-(2-bromo-phen-yl)-3-(4-methyl-phen-yl)prop-2-en-1-one], C16H13BrO, and 3'-cyano-4-methyl-chalcone {systematic name: 2-[3-(4-methyl-phen-yl)prop-2-eno-yl]benzo-nitrile}, C17H13NO. Both chalcones meaningfully add to the large dataset of chalcone structures. The crystal structure of 3'-cyano-4-methyl-chalcone exhibits close contacts with the cyano nitro-gen that do not appear in previously reported disubstituted cyano-chalcones, namely inter-actions between the cyano nitro-gen atom and a ring hydrogen atom as well as a methyl hydrogen atom. The structure of 3'-bromo-4-methyl-chalcone exhibits a type I halogen bond, similar to that found in a previously reported structure for 4-bromo-3'-methyl-chalcone.

Sodium-glucose cotransporter 2 (SGLT-2) inhibitors: a new antidiabetic drug class

Diabetes mellitus is a chronic, complex and multifactorial disease associated characteristically with hyperglycemia. One of the most recently approved antidiabetic drug classes for clinical use are sodium-glucose cotransporter type 2 (SGLT-2) inhibitors. SGLT-2 is a protein expressed in the kidneys, responsible for glucose reabsorption from the glomerular filtrate to the plasma. It is known, nowadays, that diabetic patients show an increased glucose renal reabsorption capacity, caused by the overexpression of the SGLT-2 transporter, thus contributing to hyperglycemia. From establishing this correlation, the SGLT-2 transporter started to be considered as a therapeutic target of interest, culminating in the approval of the first antidiabetic SGLT-2 inhibitor, dapagliflozin (Forxiga® or Farxiga®, Bristol-Myers Squibb & AstraZeneca), in 2012 in Europe. On the other hand, canagliflozin (Invokana®, Janssen Pharmaceutical) was the first drug in this class to be approved by the FDA, the U.S. Food and Drug Administration, in 2013. This review concerns the discovery and development of the first representatives of this class of antidiabetic drugs, and the description of new optimized analogues that are currently in the clinical and preclinical stages of development.

Recent progress of sodium-glucose transporter 2 inhibitors as potential antidiabetic agents

SGLT2 inhibitors were promising and novel antidiabetic drugs which suppressed glucose reabsorption and increased urinary glucose exertion. This review paper are aimed to summarize the recent progress of SGLT2 inhibitors during the last 5 years. This paper first summarizes the information of SGLT2 inhibitors, including mechanism, evolution and then focuses on the recent efforts on structure-activity relationships and structural optimization of SGLT2 inhibitors. Finally, the corresponding clinical therapeutic efficacy and adverse drug reaction in patients with Type 2 diabetes are discussed in detail.

Synthesis of unlabelled and stable-isotope-labelled glucuronide metabolites of dapagliflozin and synthesis of stable-isotope-labelled dapagliflozin

Two regioisomeric glucuronide metabolites of dapagliflozin (BMS-512148) were synthesized and used to elucidate the structures of dapagliflozin metabolites observed in human urine samples. The structures of the synthetic metabolites were assigned by heteronuclear multiple-bond correlation, ROESY, and total correlation spectroscopy experiments. Analogues of these metabolites containing carbon-13 as a stable label were also prepared for use as internal standards for the analysis of urine samples obtained from patients participating in clinical studies.

CoMFA and CoMSIA studies on C-aryl glucoside SGLT2 inhibitors as potential anti-diabetic agents

SGLT2 has become a target of therapeutic interest in diabetes research. CoMFA and CoMSIA studies were performed on C-aryl glucoside SGLT2 inhibitors (180 analogues) as potential anti-diabetic agents. Three different alignment strategies were used for the compounds. The best CoMFA and CoMSIA models were obtained by means of Distill rigid body alignment of training and test sets, and found statistically significant with cross-validated coefficients (q²) of 0.602 and 0.618, respectively, and conventional coefficients (r²) of 0.905 and 0.902, respectively. Both models were validated by a test set of 36 compounds giving satisfactory predicted correlation coefficients (r² pred) of 0.622 and 0.584 for CoMFA and CoMSIA models, respectively. A comparison was made with earlier 3D QSAR study on SGLT2 inhibitors, which shows that our 3D QSAR models are better than earlier models to predict good inhibitory activity. CoMFA and CoMSIA models generated in this work can provide useful information to design new compounds and helped in prediction of activity prior to synthesis.

SGLT2 inhibition in diabetes mellitus: rationale and clinical prospects

This Review covers the rationale, physiological consequences and clinical application of pharmacological sodium-glucose cotransporter 2 (SGLT2) inhibition. In patients with type 2 diabetes mellitus, in whom renal glucose reabsorption might be upregulated, orally active, selective SGLT2 inhibitors improve glycaemic control to a therapeutically useful extent. Chronic administration of several SGLT2 inhibitors dose-dependently lowers HbA(1c) levels by 0.5-1.5% without causing hypoglycaemia. The unique mechanism of action of SGLT2 inhibitors-which does not hinge upon β-cell function or tissue insulin sensitivity-means that they can exert their antihyperglycaemic effects in combination with any other oral antidiabetic drug as well as insulin. Available phase III studies confirm a good tolerability profile. Weight loss owing to urinary calorie leakage may be less than expected, but the negative energy balance offers a valuable clinical benefit. Offloading of sodium can assist blood pressure control. The progressive loss of efficacy in patients with reduced glomerular function will have to be balanced against the possibility of renal protection. The safety issues of genitourinary infections and cancer risk requires careful, proactive monitoring and analysis of robust exposure data, particularly in elderly, frail patients and in patients with impaired kidney function and/or high cardiovascular/cancer risk, who represent an increasing fraction of the population with diabetes mellitus.

Novel thiophenyl C-aryl glucoside SGLT2 inhibitors as potential antidiabetic agents

Novel thiophene C-aryl glucoside SGLT2 inhibitors were designed and synthesized. Two different types of thiophene derivatives were readily prepared. Among the compounds tested, ethylphenyl at the distal ring 71p showed the best in vitro inhibitory activity in this series to date (IC(50)=4.47 nM) against SGLT2.

Glucosides with cyclic diarylpolynoid as novel C-aryl glucoside SGLT2 inhibitors

Novel C-aryl glucoside SGLT2 inhibitors containing cyclic diarylpolynoid motif were designed and synthesized for biological evaluation. Alkylzinc bromides have been efficiently prepared by the direct insertion of zinc metal into alkyl bromides. The organozinc reagents underwent smooth Pd-catalyzed cross-coupling reactions. Subsequent ring closing metathesis using 2nd generation Grubbs catalyst successfully generated novel class of ansa-compounds. These glucosides with cyclic diarylpolynoids demonstrated moderate in vitro inhibitory activity against SGLT2 in this series to date (IC(50)=59.5-103 nM).

Thiazolylmethyl ortho-substituted phenyl glucoside library as novel C-aryl glucoside SGLT2 inhibitors

In order to investigate SAR regarding proximal phenyl ring in novel C-aryl glucoside SGLT2 inhibitors containing a thiazole motif, a series of chemical modifications on proximal phenyl ring was conducted. During a series of lead optimization efforts, ortho-allyloxyphenyl 10p or ortho-hydroxyphenyl 11a showed subnanomolar inhibitory activity against hSGLT2.

Synthesis and SAR of Thiazolylmethylphenyl Glucoside as Novel C-Aryl Glucoside SGLT2 Inhibitors

Novel C-aryl glucoside SGLT2 inhibitors containing the thiazole motif were designed and synthesized for biological evaluation. Among the compounds assayed, thiazole containing furanyl moiety 14v and thiophenyl moiety 14y demonstrated the best in vitro inhibitory activity against SGLT2 in this series to date (IC50 = 0.720 nM for 14v and IC50 = 0.772 nM for 14y). Both of these compounds have been further evaluated on a urinary glucose excretion test and the urine volumes excreted.

EGT1442, a potent and selective SGLT2 inhibitor, attenuates blood glucose and HbA(1c) levels in db/db mice and prolongs the survival of stroke-prone rats

Sodium glucose co-transporter 2 (SGLT2) is a renal type III integral membrane protein that co-transports sodium and glucose from filtrate to epithelium in the proximal tubule. Human subjects with homozygous or compound heterozygous mutations in SLC5A2 exhibit glucosuria without hypoglycemia or other obvious morbidity, suggesting that blockade of SGLT2 has the potential to promote normalization of blood glucose without hypoglycemia in the setting of type 2 diabetes. This report presents the in vitro and in vivo pharmacological activities of EGT1442, a recently discovered SGLT2 inhibitor in the C-aryl glucoside class. The inhibitory effects of EGT1442 for human SGLT1 and SGLT2 were evaluated in an AMG uptake assay and the in vivo efficacy of treatment with EGT1442 was investigated in rats and dogs after a single dose and in db/db mice after chronic administration. The effect of EGT1442 on median survival of SHRSP rats was also evaluated. The IC(50) values for EGT1442 against human SGLT1 and SGLT2 are 5.6μM and 2nM, respectively. In normal rats and dogs a saturable urinary glucose excretion was produced with an ED(50) of 0.38 and 0.09mg/kg, respectively. Following chronic administration to db/db mice, EGT1442 dose-dependently reduced HbA(1c) and blood glucose concentration without affecting body mass or insulin level. Additionally, EGT1442 significantly prolonged the median survival of SHRSP rats. EGT1442 showed favorable properties both in vitro and in vivo and could be beneficial to the management of type 2 diabetic patients.

SGLT inhibitors as new therapeutic tools in the treatment of diabetes

Recently, the idea has been developed to lower blood glucose blood glucose levels in diabetes by inhibiting sugar reabsorption sugar reabsorption in the kidney kidney . The main target is thereby the early proximal tubule proximal tubule where secondary active transport secondary active transport of the sugar is mediated by the sodium-D: -glucose D-glucose cotransporter SGLT2 SGLT2 . A model substance for the inhibitors inhibitors is the O-glucoside O-glucoside phlorizin phlorizin which inhibits transport transport competitively. Its binding to the transporter involves at least two different domains: an aglucone binding aglucone binding site at the transporter surface, involving extramembranous loops extramembraneous loops , and the sugar binding sugar binding /translocation site buried in a hydrophilic pocket of the transporter. The properties of these binding sites differ between SGLT2 and SGLT1 SGLT1 , which mediates sugar absorption sugar absorption in the intestine intestine . Various O-, C-, N- and S-glucosides have been synthesized with high affinity affinity and high specificity specificity for SGLT2 SGLT2 . Some of these glucosides are in clinical trials clinical trials and have been proven to successfully increase urinary glucose excretion urinary glucose excretion and to decrease blood sugar blood sugar levels without the danger of hypoglycaemia hypoglycaemia during fasting fasting in type 2 diabetes type 2 diabetes .

Effect of dapagliflozin in patients with type 2 diabetes who have inadequate glycaemic control with metformin: a randomised, double-blind, placebo-controlled trial

BACKGROUND

Correction of hyperglycaemia and prevention of glucotoxicity are important objectives in the management of type 2 diabetes. Dapagliflozin, a selective sodium-glucose cotransporter-2 inhibitor, reduces renal glucose reabsorption in an insulin-independent manner. We assessed the efficacy and safety of dapagliflozin in patients who have inadequate glycaemic control with metformin.

METHODS

In this phase 3, multicentre, double-blind, parallel-group, placebo-controlled trial, 546 adults with type 2 diabetes who were receiving daily metformin (>/=1500 mg per day) and had inadequate glycaemic control were randomly assigned to receive one of three doses of dapagliflozin (2.5 mg, n=137; 5 mg, n=137; or 10 mg, n=135) or placebo (n=137) orally once daily. Randomisation was computer generated and stratified by site, implemented with a central, telephone-based interactive voice response system. Patients continued to receive their pre-study metformin dosing. The primary outcome was change from baseline in haemoglobin A(1c)(HbA(1c)) at 24 weeks. All randomised patients who received at least one dose of double-blind study medication and who had both a baseline and at least one post-baseline measurement (last observation carried forward) were included in the analysis. Data were analysed by use of ANCOVA models. This trial is registered with ClinicalTrials.gov, number NCT00528879.

FINDINGS

534 patients were included in analysis of the primary endpoint (dapagliflozin 2.5 mg, n=135; dapagliflozin 5 mg, n=133; dapagliflozin 10 mg, n=132; placebo, n=134). At week 24, mean HbA(1c) had decreased by -0.30% (95% CI -0.44 to -0.16) in the placebo group, compared with -0.67% (-0.81 to -0.53, p=0.0002) in the dapagliflozin 2.5 mg group, -0.70% (-0.85 to -0.56, p<0.0001) in the dapagliflozin 5 mg group, and -0.84% (-0.98 to -0.70, p<0.0001) in the dapagliflozin 10 mg group. Symptoms of hypoglycaemia occurred in similar proportions of patients in the dapagliflozin (2-4%) and placebo groups (3%). Signs, symptoms, and other reports suggestive of genital infections were more frequent in the dapagliflozin groups (2.5 mg, 11 patients [8%]; 5 mg, 18 [13%]; 10 mg, 12 [9%]) than in the placebo group (seven [5%]). 17 patients had serious adverse events (four in each of the dapagliflozin groups and five in the placebo group).

INTERPRETATION

Addition of dapagliflozin to metformin provides a new therapeutic option for treatment of type 2 diabetes in patients who have inadequate glycaemic control with metformin alone.

FUNDING

Bristol-Myers Squibb and AstraZeneca.

C-Aryl glycoside inhibitors of SGLT2: Exploration of sugar modifications including C-5 spirocyclization

Modifications to the sugar portion of C-aryl glycoside sodium glucose transporter 2 (SGLT2) inhibitors were explored, including systematic deletion and modification of each of the glycoside hydroxyl groups. Based on results showing activity to be quite tolerant of structural change at the C-5 position, a series of novel C-5 spiro analogues was prepared. Some of these analogues exhibit low nanomolar potency versus SGLT2 and promote urinary glucose excretion (UGE) in rats. However, due to sub-optimal pharmacokinetic parameters (in particular half-life), predicted human doses did not meet criteria for further advancement.

In vitro characterization and pharmacokinetics of dapagliflozin (BMS-512148), a potent sodium-glucose cotransporter type II inhibitor, in animals and humans

(2S,3R,4R,5S,6R)-2-(3-(4-Ethoxybenzyl)-4-chlorophenyl)-6-hydroxymethyl-tetrahydro-2H-pyran-3,4,5-triol (dapagliflozin; BMS-512148) is a potent sodium-glucose cotransporter type II inhibitor in animals and humans and is currently under development for the treatment of type 2 diabetes. The preclinical characterization of dapagliflozin, to allow compound selection and prediction of pharmacological and dispositional behavior in the clinic, involved Caco-2 cell permeability studies, cytochrome P450 (P450) inhibition and induction studies, P450 reaction phenotyping, metabolite identification in hepatocytes, and pharmacokinetics in rats, dogs, and monkeys. Dapagliflozin was found to have good permeability across Caco-2 cell membranes. It was found to be a substrate for P-glycoprotein (P-gp) but not a significant P-gp inhibitor. Dapagliflozin was not found to be an inhibitor or an inducer of human P450 enzymes. The in vitro metabolic profiles of dapagliflozin after incubation with hepatocytes from mice, rats, dogs, monkeys, and humans were qualitatively similar. Rat hepatocyte incubations showed the highest turnover, and dapagliflozin was most stable in human hepatocytes. Prominent in vitro metabolic pathways observed were glucuronidation, hydroxylation, and O-deethylation. Pharmacokinetic parameters for dapagliflozin in preclinical species revealed a compound with adequate oral exposure, clearance, and elimination half-life, consistent with the potential for single daily dosing in humans. The pharmacokinetics in humans after a single dose of 50 mg of [(14)C]dapagliflozin showed good exposure, low clearance, adequate half-life, and no metabolites with significant pharmacological activity or toxicological concern.