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1,508 result(s) for "Phenothiazines"
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Development of Phenothiazine Hybrids with Potential Medicinal Interest: A Review
The molecular hybridization approach has been used to develop compounds with improved efficacy by combining two or more pharmacophores of bioactive scaffolds. In this context, hybridization of various relevant pharmacophores with phenothiazine derivatives has resulted in pertinent compounds with diverse biological activities, interacting with specific or multiple targets. In fact, the development of new drugs or drug candidates based on phenothiazine system has been a promising approach due to the diverse activities associated with this tricyclic system, traditionally present in compounds with antipsychotic, antihistaminic and antimuscarinic effects. Actually, the pharmacological actions of phenothiazine hybrids include promising antibacterial, antifungal, anticancer, anti-inflammatory, antimalarial, analgesic and multi-drug resistance reversal properties. The present review summarizes the progress in the development of phenothiazine hybrids and their biological activity.
Exploitation of a novel phenothiazine derivative for its anti-cancer activities in malignant glioblastoma
Glioblastoma remains the most malignant of all primary adult brain tumours with poor patient survival and limited treatment options. This study adopts a drug repurposing approach by investigating the anti-cancer activity of a derivative of the antipsychotic drug phenothiazine (DS00329) in malignant U251 and U87 glioblastoma cells. Results from MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) and clonogenic assays showed that DS00329 inhibited short-term glioblastoma cell viability and long-term survival while sparing non-cancerous cells. Western blot analysis with an antibody to γH2AX showed that DS00329 induced DNA damage and flow cytometry and western blotting confirmed that it triggered a G1 cell cycle arrest which correlated with decreased levels in Cyclin A, Cyclin B, Cyclin D1 and cyclin dependent kinase 2 and an increase in levels of the cyclin dependent kinase inhibitor p21. DS00329 treated glioblastoma cells exhibited morphological and molecular markers typical of apoptotic cells such as membrane blebbing and cell shrinkage and an increase in levels of cleaved PARP. Flow cytometry with annexin V-FITC/propidium iodide staining confirmed that DS00329 induced apoptotic cell death in glioblastoma cells. We also show that DS00329 treatment of glioblastoma cells led to an increase in the autophagosome marker LC3-II and autophagy inhibition studies using bafilomycin A1 and wortmannin, showed that DS00329-induced-autophagy was a pro-death mechanism. Furthermore, DS00329 treatment of glioblastoma cells inhibited the phosphatidylinositol 3′-kinase/Akt cell survival pathway. Our findings suggest that DS00329 may be an effective treatment for glioblastoma and provide a rationale for further exploration and validation of the use of phenothiazines and their derivatives in the treatment of glioblastoma.
Identification of phenothiazine derivatives as UHM-binding inhibitors of early spliceosome assembly
Interactions between U2AF homology motifs (UHMs) and U2AF ligand motifs (ULMs) play a crucial role in early spliceosome assembly in eukaryotic gene regulation. UHM-ULM interactions mediate heterodimerization of the constitutive splicing factors U2AF65 and U2AF35 and between other splicing factors that regulate spliceosome assembly at the 3′ splice site, where UHM domains of alternative splicing factors, such as SPF45 and PUF60, contribute to alternative splicing regulation. Here, we performed high-throughput screening using fluorescence polarization assays with hit validation by NMR and identified phenothiazines as general inhibitors of UHM-ULM interactions. NMR studies show that these compounds occupy the tryptophan binding pocket of UHM domains. Co-crystal structures of the inhibitors with the PUF60 UHM domain and medicinal chemistry provide structure-activity-relationships and reveal functional groups important for binding. These inhibitors inhibit early spliceosome assembly on pre-mRNA substrates in vitro. Our data show that spliceosome assembly can be inhibited by targeting UHM-ULM interactions by small molecules, thus extending the toolkit of splicing modulators for structural and biochemical studies of the spliceosome and splicing regulation. So far only a few compounds have been reported as splicing modulators. Here, the authors combine high-throughput screening, chemical synthesis, NMR, X-ray crystallography with functional studies and develop phenothiazines as inhibitors for the U2AF Homology Motif (UHM) domains of proteins that regulate splicing and show that they inhibit early spliceosome assembly on pre-mRNA substrates in vitro.
Quantum chemical modeling, molecular docking, and ADMET evaluation of imidazole phenothiazine hybrids
Cancer is one of the biggest challenges for health concerns in the world. There are so many drugs available, but they have a lack of specificity, poor safety, side effects, and the development of resistance. Therefore, there is an urgent need for much safer and more targeted anticancer treatments. Nitrogen-containing heterocycles play an important role in the development of drugs. Recently, imidazole and phenothiazine rings are well known for their antiproliferative and anticancer activities. This study employs the molecular hybridisation method to link these bioactive scaffolds and develop novel N -substituted imidazole-phenothiazine ( N -IPTZ) hybrids. All the synthesised hybrids were characterised by using analytical techniques such as 1 H-NMR, 13 C-NMR, mass spectrum, and FT-IR. Furthermore, the DFT analysis under the B3LYP/6-311G(d, p) level in gas phase to optimise and correlate the structures of the synthesised hybrids was also performed. The optimised structure was used to determine the energies of frontier molecular orbitals (HOMO-LUMO), quantum chemical descriptors (QCD), and molecular electrostatic potentials (MEP). Additionally, in silico approaches such as ADMET, BOILED-Egg, and bioactivity radar were also performed to evaluate the oral bioavailability of the synthesised hybrids. Molecular docking and MD simulation studies were also conducted to assess the interaction profile of the synthesised hybrids with cancer target receptors like EGFR, IGF, VEGFR1, VEGFR2, and PARP-2. It was found through docking studies that the synthesised N -IPTZ(a-c) hybrids might interact with amino acids such as GLY695, SER696, GLY697, ALA698, PHE699, LYS721, GLY772, CYS773, THR766, GLN767, LEU768, MET769, ARG817, ASN818, and THR830. Additionally, it reveals hydrogen bonding with ASP831, with binding energies of − 7.23, − 6.11, and − 5.93 kcal/mol. Moreover, all the synthesised hybrids were also analysed for their anti-cancer activity against the human liver cancer cell line (HepG2) by MTT assay. Obtained results revealed that N -IPTZ(c) exhibited anticancer activity with an IC 50 value of 35.3 µg/mL.
Synthesis and biological evaluation of ortho -phenyl phenylhydroxamic acids containing phenothiazine with improved selectivity for class IIa histone deacetylases
Class IIa histone deacetylases (HDACs) have been linked to tumorigenesis in various cancers. Previously, we designed phenylhydroxamic acid as a potent class IIa HDAC inhibitor. However, it also unselectively inhibited class I and class IIb HDACs. To enhance the compound's selectivity towards class IIa HDACs, the -phenyl group from the selective HDAC7 inhibitor is incorporated into position of the phenylhydroxamic acid in . Compared to , most resulting compounds displayed substantially improved selectivity towards the class IIa HDACs. Notably, compound exhibited the strongest HDAC9 inhibition with an IC value of 40 nM. Molecular modelling further identified the key interactions of compound bound to HDAC9. Compound significantly inhibited several human cancer cells, induced apoptosis, modulated caspase-related proteins as well as p38, and caused DNA damage. These findings suggest the potential of class IIa HDAC inhibitors as lead compounds for the development of cancer therapeutics.
Novel 3-Methyl-1,6-Diazaphenothiazine as an Anticancer Agent—Synthesis, Structure, and In Vitro Anticancer Evaluation
Pyridine derivatives are widely distributed in nature and have valuable pharmacological properties. The pyridine core can be found in drugs such as sorafenib, zapiclone or prothipendyl. Dipyridothiazines are derivatives of phenothiazines that exhibit valuable anticancer, antioxidant and immunomodulatory activities. In this study, we present the synthesis and preliminary in vitro analysis of anticancer activity towards melanotic (COLO829, G361) and amelanotic (A375, C32) melanoma cells and normal human fibroblasts (HDF) of a series of new tricyclic diazaphenothiazines containing a pyridine scaffold in their structure. The structures of these new molecules was confirmed using spectral techniques, including 1H NMR, 13C NMR, 2D NMR and HRMS. An in vitro panel of experiments was assessed using the WST-1 assay and cytometric techniques. The two most promising compounds were analyzed for their effect on intracellular GSH levels, mitochondrial membrane potential and their ability to initiate DNA fragmentation to determine the potential mechanism of both cytotoxic and proapoptotic activity. The conducted studies confirmed the ability of the new 3-methyl-1,6-diazaphenothiazines to induce apoptosis in cancer cells, especially in terms of inducing initial as well as late-phase apoptosis. Moreover, the studied compounds were found to induce redox imbalance (evidenced by GSH depletion) in the analyzed melanoma cells, which may be an important factor that directs melanoma cells towards cell death signaling pathways.
Synthesis of New Phenothiazine/3-cyanoquinoline and Phenothiazine/3-aminothieno2,3-bpyridine(-quinoline) Heterodimers
The aim of this work was to prepare new heterodimeric molecules containing pharmacophoric fragments of 3-cyanoquinoline/3-aminothieno[2,3-b]pyridine/3-aminothieno[2,3-b]quinoline on one side and phenothiazine on the other. The products were synthesized via selective S-alkylation of readily available 2-thioxo-3-cyanopyridines or -quinolines with N-(chloroacetyl)phenothiazines, followed by base-promoted Thorpe–Ziegler isomerization of the resulting N-[(3-cyanopyridin-2-ylthio)acetyl]phenothiazines. We found that both the S-alkylation and the Thorpe–Ziegler cyclization reactions, when conducted with KOH under heating, were accompanied to a significant extent by a side reaction involving the elimination of phenothiazine. Optimization of the conditions (0–5 °C, anhydrous N,N-dimethylacetamide and NaH or t-BuONa as non-nucleophilic bases) minimized the side reaction and increased the yields of the target heterodimers. The structures of the products were confirmed by IR spectroscopy, 1H, and 13C DEPTQ NMR studies. It was demonstrated that the synthesized 3-aminothieno[2,3-b]pyridines can be acylated with chloroacetyl chloride in hot chloroform. The resulting chloroacetamide derivative reacts with potassium thiocyanate in DMF to form the corresponding 2-iminothiazolidin-4-one; in this process, phenothiazine elimination does not occur, and the Gruner–Gewald rearrangement product was not observed. The structural features and spectral characteristics of the synthesized 2-iminothiazolidin-4-one derivative were investigated by quantum chemical methods at the B3LYP-D4/def2-TZVP level. A range of drug-relevant properties was also evaluated using in silico methods, and ADMET parameters were calculated. A molecular docking study identified a number of potential protein targets for the new heterodimers, indicating the promise of these compounds for the development of novel antitumor agents.
Novel Tetracyclic Azaphenothiazines with the Quinoline Ring as New Anticancer and Antibacterial Derivatives of Chlorpromazine
Phenothiazine derivatives are widely studied in various fields such as biology, chemistry, and medicine research because of their pharmaceutical effects. The first compound used successfully in the treatment of psychosis was a phenthiazine derivative, chlorpromazine. Apart from its activity in neurons, chlorpromazine has also been reported to display anticancer and antibacterial properties. In this study, we present the synthesis and research on the activity of A549, MDA, MiaPaCa, PC3, and HCT116 cancer cell lines and of S. aureus, S. epidermidis, E. coli, and P. aeruginosa bacterial strains against a series of new tetracyclic chlorpromazine analogues containing a quinoline scaffold in their structure instead of the benzene ring and various substituents at the thiazine nitrogen. The structure of these novel molecules has been determined by 1H NMR, 13C NMR, and HRMS spectral techniques. The seven most active of the twenty-four new chlorpromazine analogues tested were selected to study the mechanism of cytotoxic action. Their ability to induce apoptosis or necrosis in cancer cells was assessed by flow cytometry analysis. The results obtained confirmed the proapoptotic activity of selected compounds, especially in terms of inducing late apoptosis or necrosis in cancer cell lines A549, MiaPaCa-2, and HCT-116. Furthermore, studies on the induction of cell cycle arrest suggest that the new chlorpromazine analogues exert antiproliferative effects by inducing cell cycle arrest in the S phase and, consequently, apoptosis.
Antioxidative Properties of Melanins and Ommochromes from Black Soldier Fly Hermetia illucens
A comparative study of melanin and ommochrome-containing samples, isolated from the black soldier fly (BSF) by enzymatic hydrolysis, alkaline and acid alcohol extraction or by acid hydrolysis, was carried out. Melanin was isolated both as a melanin-chitin complex and as a water-soluble melanin. Acid hydrolysis followed by delipidization yielded a more concentrated melanin sample, the electron spin resonance (ESR) signal of which was 2.6 × 1018 spin/g. The ommochromes were extracted from the BSF eyes with acid methanol. The antiradical activity of BSF melanins and ommochromes was determined by the method of quenching of luminol chemiluminescence. It has been shown that delipidization of water-soluble melanin increases its antioxidant properties. A comparison of the antioxidant activity of BSF melanins and ommochromes in relation to photoinduced lipid peroxidation was carried out. The ESR characteristics of native and oxidized melanins and ommochromes were studied. It is assumed that H. illucens adult flies can be a useful source of natural pigments with antioxidant properties.
Synthesis, Electronic, and Antibacterial Properties of 3,7-Di(hetero)aryl-substituted Phenothiazinyl N-Propyl Trimethylammonium Salts
In this study, a library of 3,7-di(hetero)aryl-substituted 10-(3-trimethylammoniumpropyl)10H-phenothiazine salts is prepared. These title compounds and their precursors are reversible redox systems with tunable potentials. The Hammett correlation gives a very good correlation of the first oxidation potentials with σp parameters. Furthermore, the title compounds and their precursors are blue to green-blue emissive. Screening of the salts reveals for some derivatives a distinct inhibition of several pathogenic bacterial strains (Mycobacterium tuberculosis, Staphylococcus aureus, Escherichia coli, Aconetobacter baumannii, and Klebsiella pneumoniae) in the lower micromolar range.