Novel thiazolidinedione-hydroxamates as inhibitors of Mycobacterium tuberculosis virulence factor Zmp1

Novel NO-TZDs and trimethoxychalcone-based DHPMs: design, synthesis, and biological evaluation as potential VEGFR-2 inhibitors

Novel series of nitric oxide-releasing thiazolidine-2,4-diones (NO-TZD-3a-d,5,6) and 3,4,5-trimethoxychalcone-based multifunctional 1,4-dihydropyrimidines (CDHPM-10a-g) have been designed and synthesised as potent broad-spectrum anticancer agents with potential VEGFR-2 inhibition. The designed analogs were evaluated for their anticancer activities towards a full panel of NCI-60 tumour cell lines and CDHPM-10a-g emerged mean %inhibitions ranging from 76.40 to 147.69%. Among them, CDHPM-10e and CDHPM-10f demonstrated the highest MGI% of 147.69 and 140.24%, respectively. Compounds CDHPM-10a,b,d-f showed higher mean %inhibitory activity than the reference drug sorafenib (MGI% = 105.46%). Superiorly, the hybrid CDHPM-10e displayed the highest potencies towards all the herein tested subpanels of nine types of cancer with MGI50 of 1.83 µM. Also, it revealed potent cytostatic single-digit micromolar activity towards the herein examined cancer cell lines. The designed compounds CDHPM-10a-g were exposed as potent non-selective broad-spectrum anticancer agents over all NCI subpanels with an SI range of 0.66-1.97. In addition, the target analog CDHPM-10e revealed potency towards VEGFR-2 kinase comparable to that of sorafenib with a sub-micromolar IC50 value of 0.11 µM. Also, CDHPM-10e could effectively induce Sub-G1-phase arrest and prompt apoptosis via caspase and p53-dependent mechanisms. Furthermore, CDHPM-10e revealed significant anti-metastatic activity as detected by wound healing assay. The modelling study implies that CDHPM-10e overlaid well with sorafenib and formed a strong H-bond in the DFG binding domain. The ADMET studies hinted out that CDHPM-10e met Pfizer's drug-likeness criteria. The presented novel potent anticancer agent merits further devotion as a new lead product in developing more chalcone-based VEGFR-2 inhibitors.

Design and synthesis of 9-phenanthranilamide derivatives and the study of anti-inflammatory, antioxidant and neuroprotective activities

Oxidative stress and a series of excessive inflammatory responses are major obstacles to neurological functional recovery after ischemic stroke. In this study, we synthesized several novel 9-phenanthranilamide derivatives and evaluated their anti-inflammatory and antioxidant activities. Among the initially screened compounds, most could strongly inhibi lipopolysaccharide (LPS)-stimulated production of IL-1β, IL-6 and TNF-α in microglial cells. Additionally, compounds 8b, 8q, 8r and 8s significantly inhibited the production of NO, and they also had dose-dependent protective effects on PC12 neuronal cells induced by H2O2. The antineuroinflammatory effects of 8r and 8s were associated with the downregulation of LPS-induced inflammatory mediators of nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) and both compounds inhibited the NF-κB signaling pathway. Further examinations showed that 8s had a significant neuroprotective effect on rats with middle cerebral artery occlusion (MCAO). It decreased the infarct volume and the neurological deficit score. Overall, our results suggested that compound 8s might be a promising agent for stroke treatment.

The use of matrix-assisted laser desorption/ionization mass spectrometry in enzyme activity assays and its position in the context of other available methods

Activity assays are indispensable for studying biochemical properties of enzymes. The purposes of measuring activity are wide ranging from a simple detection of the presence of an enzyme to kinetic experiments evaluating the substrate specificity, reaction mechanisms, and susceptibility to inhibitors. Common activity assay methods include spectroscopy, electrochemical sensors, or liquid chromatography coupled with various detection techniques. This review focuses on the use of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) as a growing and modern alternative, which offers high speed of analysis, sensitivity, versatility, possibility of automation, and cost-effectiveness. It may reveal reaction intermediates, side products or measure more enzymes at once. The addition of an internal standard or calculating the ratios of the substrate and product peak intensities and areas overcome the inherent inhomogeneous distribution of analyte and matrix in the sample spot, which otherwise results in a poor reproducibility. Examples of the application of MALDI-TOF MS for assaying hydrolases (including peptidases and β-lactamases for antibiotic resistance tests) and other enzymes are provided. Concluding remarks summarize advantages and challenges coming from the present experience, and draw future perspectives such as a screening of large libraries of chemical compounds for their substrate or inhibitory properties towards enzymes.

New Succinimide-Thiazolidinedione Hybrids as Multitarget Antidiabetic Agents: Design, Synthesis, Bioevaluation, and Molecular Modelling Studies

Diabetes mellitus (DM) is a metabolic disorder majorly arising from the pathophysiology of the pancreas manifested as a decline in the insulin production or the tissue's resistance to the insulin. In this research, we have rationally designed and synthesized new succinimide-thiazolidinedione hybrids for the management of DM. In a multistep reaction, we were able to synthesize five new derivatives (10a-e). All the compounds were new containing a different substitution pattern on the N-atom of the succinimide ring. Initially, all the compounds were tested against the in vitro α-glucosidase, α-amylase, PTP1B, and DPP4 targets. In all of these targets, the compound 10d was observed to be the most potential antidiabetic agent. Based on this, the antidiabetic activity of the compound 10d was further investigated in experimental animals, which overall gave us encouraging results. The molecular docking studies of the compound 10d was also performed against the target enzymes α-glucosidase, α-amylase, PTP1B, and DPP4 using MOE. Overall, we observed that we have explored a new class of compounds as potential antidiabetic agents.

The medicinal perspective of 2,4-thiazolidinediones based ligands as antimicrobial, antitumor and antidiabetic agents: A review

2,4-Thiazolidinedione (2,4-TZD), commonly known as glitazone, is a ubiquitous heterocyclic pharmacophore possessing a plethora of pharmacological activities and offering a vast opportunity for structural modification. The diverse range of biological activities endowed with a novel mode of action, low cost, and easy synthesis has attracted the attention of medicinal chemists. Several researchers have integrated the TZD core with different structural fragments to develop a wide range of lead molecules against various clinical disorders. The most common sites for structural modifications at the 2,4-TZD nucleus are the N-3 and the active methylene at C-5. The review covers the recent development of TZD derivatives such as antimicrobial, anticancer, and antidiabetic agents. Various 2,4-TZD based agents or drugs, which are either under clinical development or in the market, are discussed in the study. Different synthetic methodologies for synthesizing the 2,4-TZD core are also included in the manuscript. The importance of various substitutions at N-3 and C-5 and the mechanisms of action and structure-activity relationships are also discussed. We hope this study will serve as a valuable tool for the scientific community engaged in the structural exploitation of the 2,4-TZD core for developing novel drug m\olecules for life-threatening ailments.

Thiazolidinedione-Based Structure Modification of Celastrol Provides Thiazolidinedione-Conjugated Derivatives as Potent Agents against Non-Small-Cell Lung Cancer Cells through a Mitochondria-Mediated Apoptotic Pathway

In order to improve the potential of celastrol against non-small-cell lung cancer cells, the privileged structure, thiazolidinedione, was introduced into its C-20 carboxylic group with acetylpiperazine as a linker, and the thiazolidinedione-conjugated compounds 10a-10t were prepared. The target compounds were evaluated for their cytotoxic activities against the A549 cell line, and the results showed that most of the compounds 10a-10t displayed improved potency over celastrol, and compound 10b exhibited significant activity against the A549 cell line, with an IC₅₀ value of 0.08 μM, which was 13.8-fold more potent than celastrol (IC₅₀ = 1.10 μM). The mechanistic studies suggested that 10b could induce A549 cell apoptosis, as evidenced by Hoechst 33342 staining and annexin V-FITC/propidium iodide dual staining assays. Western blot analysis suggested that compound 10b could upregulate Bax expression, downregulate Bcl-2 expression, and activate the mitochondria-mediated apoptotic pathway. Furthermore, compound 10b could effectively inhibit tumor growth when tested in an A549 cell xenograft mouse model. Collectively, compound 10b is worthy of further investigation to support the discovery of effective agents against non-small-cell lung cancer.

Catalyst-Controlled Regiodivergent Synthesis of α/β-Dipeptide Derivatives via N-Allylic Alkylation of O-Alkyl Hydroxamates with MBH Carbonates

A controllable and regiodivergent N-allylation reaction involving readily available O-alkyl hydroxamates derived from natural α-amino acids has been developed, allowing regiospecific access to α/β-dipeptides containing α-unsaturated β-amino acids moieties in moderate to good yields. The regioselectivity could be conveniently switched by alternation of the catalysts and solvents.

The Bioactivity of Thiazolidin-4-Ones: A Short Review of the Most Recent Studies

Thiazolidin-4-ones is an important heterocyclic ring system of a pharmacophore and a privileged scaffold in medicinal chemistry. This review is focused on the latest scientific reports regarding biological activities of thiazolidin-4-ones published in 2020 and 2021. The review covers recent information about antioxidant, anticancer, anti-inflammatory, analgesic, anticonvulsant, antidiabetic, antiparasitic, antimicrobial, antitubercular and antiviral properties of thiazolidin-4-ones. Additionally, the influence of different substituents in molecules on their biological activity was discussed in this paper. Thus, this study may help to optimize the structure of thiazolidin-4-one derivatives as more efficient drug agents. Presented information may be used as a practical hint for rational design of new small molecules with biological activity, especially among thiazolidin-4-ones.

Hybridization Approach to Drug Discovery Inhibiting Mycobacterium tuberculosis-An Overview

Tuberculosis is one of the top 10 causes of death worldwide and the leading cause of death from a single infectious agent, mainly due to Mycobacterium tuberculosis (MTB). Recently, clinical prognoses have worsened due to the emergence of multi-drug resistant (MDR) and extensive-drug resistant (XDR) tuberculosis, which lead to the need for new, efficient and safe drugs. Among the several strategies, polypharmacology could be considered one of the best solutions, in particular, the multitarget directed ligands strategy (MTDLs), based on the synthesis of hybrid ligands acting against two targets of the pathogen. The framework strategy comprises linking, fusing and merging approaches to develop new chemical entities. With these premises, this review aims to provide an overview of the recent hybridization approach, in medicinal chemistry, of the most recent and promising multitargeting antimycobacterial candidates.

Antitubercular properties of thiazolidin-4-ones - A review

Thiazolidin-4-one scaffold has great potential for medicinal chemistry and is of interest to scientists in view of wide spectrum of biological activity. This scaffold is often used for designing of small molecules with various biological activity including antituberculosis activity. The presented review is an attempt to gather, analyze and systemize data about antitubercular properties of thiazolidine-4-ones from two last decades. Some of them have promising antitubercular activity which is significantly higher than that of the reference drugs. Among them compounds 82c, 82d and 84 that were active against M. tuberculosis H37Rv strain with MICs in the range of 0.05-0.2 μg/mL and compound 108 exhibited activity with MIC = 0.36 μM. Compounds 115a-115c and 116a-116c were very effective against M. tuberculosis H37Ra with MIC values in the range of 0.031-0.125 μg/mL. Acidomycin was showed activity against seven MDR M. tuberculosis strains with MICs in the range of 0.6-0.62 μM and against two XDR M. tuberculosis strains with MICs 0.096 and 1.2 μM. The structure-activity relationship (SAR) of some groups of compounds, as well as some potential molecular targets were also discussed.

Novel stilbene scaffolds efficiently target Mycobacterium tuberculosis nucleoid-associated protein, HU

Novel scaffolds of stilbene were identified as inhibitors of Mycobacterium tuberculosis by targeting the nucleoid-associated protein, HU, using molecular docking.

Structural analysis of Mycobacterium tuberculosis M13 metalloprotease Zmp1 open states

Zinc metalloprotease 1 (Zmp1), a Mycobacterium tuberculosis 75 kDa secreted enzyme, mediates key stages of tuberculosis disease progression. The biological activity of Zmp1 presumably stems from its ability to degrade bacterium- and/or host-derived peptides. The crystal structures of Zmp1 and related M13 metalloproteases, such as neprilysin and endothelin-converting enzyme-1 were determined only in the closed conformation, which cannot capture substrates or release proteolytic products. Thus, the mechanisms of substrate binding and selectivity remain elusive. Here we report two open-state cryo-EM structures of Zmp1, revealed by our SAXS analysis to be the dominant states in solution. Our structural analyses reveal how ligand binding induces a conformational switch in four linker regions to drive the rigid body motion of the D1 and D2 domains, which form the sizable catalytic chamber. Furthermore, they offer insights into the catalytic cycle and mechanism of substrate recognition of M13 metalloproteases for future therapeutic innovations.