Search Results (11)

Phenothiazines, mainly known for their antipsychotic activity, have recently attracted attention as potential compounds with anticancer and immunomodulatory activity In this study, 20 new quinobenzothiazines (MJ1–MJ20) were synthesized and their effects on normal cell lines (BEAS-2B, NHDF) and cancer cell lines (HCT116, MCF7, A549, SH-SY5Y, U2OS) were investigated. The studies included cytotoxicity assessment, analysis of the expression of genes (BCL2, AIFM2, MDM2) and pro-inflammatory cytokines (IL6, IL8) using the RT-qPCR method, and prediction of biological activity using the PASS platform. The results indicate that the compounds MJ19 and MJ20 have the greatest effect on the induction of pro-inflammatory (IL6, IL8) and antiapoptotic (BCL2, MDM2) genes, suggesting their potential use in therapies for inflammatory and autoimmune diseases. Gene expression analysis showed that compound MJ2 in BEAS-2B cells significantly induced the expression of AIFM2, a protein responsible for protecting against ferroptosis, while moderately increasing the expression of BCL2 and MDM2, suggesting a potential role for MJ2 in the modulation of protective mechanisms of healthy cells, e.g., avoiding apoptosis death. These results emphasize the potential of quinobenzothiazines as multifunctional bioactive compounds, which require further studies to determine their mechanisms of action and specificity. Full article

Hyperlipidemia, marked by high levels of fats in the blood, is a major risk factor for non-communicable diseases such as type 2 diabetes, cardiovascular diseases, and cancer. It has been linked to the action of reactive oxygen species and the formation of advanced glycation end products. Current treatments for hyperlipidemia, like orlistat, simvastatin, and atorvastatin, often present undesirable side effects, prompting the need for new therapeutic agents that are safer, more effective, cost-efficient, and have fewer side effects. In this context, new compounds, specifically propano- and butanosulfonic acids with 9-substituted quinobenzothiazinyl substituents, were synthesized through reactions with 9-substituted quinobenzothiazines and propane sultone or butane sultone. These novel quinobenzothiazine derivatives were verified using ¹H NMR, ¹³C NMR, and HR-MS techniques. The research focused on assessing these compounds for their toxicity, ability to prevent glycation, antioxidant properties, and their potential to combat hyperlipidemia. Toxicity was evaluated on the 3T3 L1 fibroblast cell line using the MTT assay. The capacity to prevent glycation was tested with bovine serum albumin–methylglyoxal and bovine serum albumin–glucose systems. This study measured total reactive oxygen species in the 3T3 L1 cell line using 2′,7′-dichlorodihydrofluorescein diacetate staining, and antioxidant capacity was assessed through DPPH scavenging and metal ion chelation tests. The effectiveness against hyperlipidemia was determined by targeting cholesterol esterase and pancreatic lipase activities, with concentrations of the compounds 5 to 12 ranging from 0.0245 to 0.268 μM. Standard drugs such as orlistat, simvastatin, statins, and aminoguanidine were used as positive controls in various assays. Additionally, computational docking studies with AutoDock Vina were performed. The resulting findings indicated that the compounds were non-toxic to cells, effectively inhibited key enzymes related to hyperlipidemia, and showed significant antioxidant properties, including the prevention of advanced glycation end-product formation. Compounds 11 and 12 demonstrated the highest activity levels. These promising results highlight the potential of new quinobenzothiazine derivatives as lead compounds for the development of antihyperlipidemic drugs, although further research is necessary to confirm their efficacy and safety. Full article

Objectives: Cancer remains one of the leading causes of death worldwide, and thus, there is a need for the development of innovative and more effective treatment strategies. The aim of the study was to evaluate two types of nanoparticles—nanospheres and micelles—obtained from PLA-based polymers to discover their potential for delivering four types of phenothiazine derivatives. Methods: The morphology, drug-loading properties, cytocompatibility, hemolytic properties and anticancer activity were analyzed. Results: The micelles exhibited significantly higher drug-loading properties, release process and cytotoxic activity against cancer cells compared to the nanospheres. The micelles containing 5-methyl-12H-quino[3,4-b][1,4]benzothiazinium chloride with an OH group as a substituent in the 10-position of the quinobenzothiazine ring showed the highest drug-loading content, the most efficient drug release, the lowest hemolytic activity and the most significant cytotoxic effect against HeLa cells. Conclusions: The conducted study enabled the development of a delivery system for the new anticancer compound and showed that the choice of drug carrier has a crucial effect on its cytotoxic potential against cancer cells. Full article

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. Full article

In this paper, we describe a new method for synthesizing hybrid combinations of 1,2,3-triazoles with a tetracyclic quinobenzothiazinium system. The developed approach allowed for the production of a series of new azaphenothiazine derivatives with the 1,2,3-triazole system in different positions of the benzene ring. In practice, the methodology consists of the reaction of triazole aniline derivatives with thioquinanthrenediinium bis-chloride. The structure of the products was determined by ¹H-NMR, ¹³C-NMR spectroscopy, and HR-MS spectrometry, respectively. Moreover, the spatial structure of the molecule and the arrangement of molecules in the crystal (unit cell) were determined by X-ray crystallography. The anticancer activity profiles of the synthesized compounds were tested in vitro against human cancer cells of the A549, SNB-19, and T47D lines and the normal NHDF cell line. Additional tests of antibacterial activity against methicillin-sensitive and methicillin-resistant staphylococci, vancomycin-sensitive and vancomycin-resistant enterococci, and two mycobacterial strains were also performed. In fact, the dependence of anticancer and antibacterial activity on the substituent type and its position in the quinobenzothiazinium system was observed. Furthermore, the distance-guided property evaluation was performed using principal component analysis (PCA) and hierarchical clustering analysis (HCA) on the pool of the calculated descriptors. Finally, the theoretically approximated partition coefficients (clogP) were (inter-)correlated with each other and cross-compared with the empirically specified logP_TLC parameters. Full article

The antitumor potency of a series of designed and prepared antibacterial quinobenzothiazines was evaluated against different types of human cancer cell lines, such as glioblastoma SNB-19, lung adenocarcinoma A549 and breast cancer T47D, and the activities of the compounds were compared to cisplatin and doxorubicin. 9-Propoxy-5-methyl-12H-quino[3,4-b][1,4]benzo- thiazinium chloride (4a), 9-allyloxy-5-methyl-12H-quino[3,4-b][1,4]benzothiazinium chloride (4d) and 11-benzyloxy-5-methyl-12H-quino[3,4-b][1,4]benzothiazinium chloride (4l) were the most active compounds; their IC₅₀ values against all three cell lines ranged from 5.3 to 9.3 µM. The effective derivatives showed no cytotoxic effect up to 100 µM on normal human dermal fibroblasts (NHDFs). To explore the structure–activity relationship, the effect of the type/nature and position of the substituents on the tetracyclic quinobenzothiazine system on the anticancer activity was investigated. Additionally, the receptor-dependent approach was used to specify the mutual ligand–enzyme (bio)compositions that might be potentially valid for the antitumor characteristics of new quinobenzothiazine derivatives. In particular, the molecular docking procedure was applied for the most potent agents against the human breast cancer line T47D in order to obtain comprehensive knowledge about the aromatase–inhibitor binding mode. The docking study revealed that some regularities in the spatial atomic distribution and nonbonding interactions (e.g., hydrophobic patterns) can be observed for the most active molecules. The surface of the electron-rich aromatic rings of 4d and 4l molecules could also contribute to π–π stacking interactions with protoporphyrin IX (HEM) as well as to the formation of π–cation interactions with the adjacent iron cofactor. Full article

Synthesis of anticancer substances and studying their binding abilities towards human serum proteins as carriers are important parts of pharmaceutical and medical sciences development. The presented work is a continuation of studies of quinobenzothiazine derivatives binding with serum proteins. The main aim of this work was a spectroscopic analysis of second from benzothiazinium derivatives salt, 9-fluoro-5-alkyl-12(H)-quino [3,4-b][1,4]benzothiazinium chloride (Salt2), its interaction with carrier proteins, i.e., human serum albumin (HSA), α₁-acid glycoprotein (AGP), human gamma globulin (HGG), and the study of protein secondary and tertiary structure changes using spectroscopic techniques (spectrofluorescence, UV-Vis and circular dichroism CD spectroscopy). In order to mimic in vivo conditions, control normal serum (CNS) was used. Using the Klotz method, both binding constants (K_a [M⁻¹]) and the number of binding classes (n) were calculated. In addition, the percentage of displacement of binding site markers from HSA and AGP molecules has been defined. Based on the obtained data, it can be concluded that the main binding protein for Salt2 is AGP. HSA and HGG are also involved in the distribution of the studied substance in the bloodstream. Moreover, Salt2 very slightly interacts with CNS, which can cause strong therapeutic as well as toxic effects. The analysis of CD spectra confirms that there are no changes in the secondary structure of the main binding proteins in the presence of Salt2. Full article

A new method for modifying the structure of tetracyclic quinobenzothiazinium derivatives has been developed, allowing introduction of various substituents at different positions of the benzene ring. The method consists of reacting appropriate aniline derivatives with 5,12-(dimethyl)thioquinantrenediinium bis-chloride. A series of new quinobenzothiazine derivatives was obtained with propyl, allyl, propargyl and benzyl substituents in 9, 10 and 11 positions, respectively. The structure of the obtained compounds was analyzed by ¹H and ¹³C NMR (HSQC, HMBC) and X-ray analysis. All the compounds were tested against reference strains Staphylococcus aureus ATCC 29213 and Enterococcus faecalis ATCC 29212, and representatives of multidrug-resistant clinical isolates of methicillin-resistant S. aureus (MRSA) and vancomycin-resistant E. faecalis (VRE). In addition, all the compounds were evaluated in vitro against Mycobacterium smegmatis ATCC 700084 and M. marinum CAMP 5644. 9-Benzyloxy-5-methyl-12H-quino [3,4-b][1,4]benzothiazinium chloride (6j), 9-propoxy-5-methyl-12H-quino[3,4-b][1,4]benzothiazinium chloride (6a) and 9-allyloxy-5-methyl-12H-quino[3,4-b][1,4]benzothiazinium chloride (6d) demonstrated high activity against the entire tested microbial spectrum. The activities of the compounds were comparable with oxacillin, tetracycline and ciprofloxacinagainst staphylococcal strains and with rifampicin against both mycobacterial strains. Compound 6j had a significant effect on the inhibition of bacterial respiration as demonstrated by the MTT assay. The compounds showed not only bacteriostatic activity, but also bactericidal activity. Preliminary in vitro cytotoxicity screening of the compounds performed using normal human dermal fibroblasts (NHDF) proved that the tested compounds showed an insignificant cytotoxic effect on human cells (IC₅₀ > 37 µM), making these compounds interesting for further investigation. Moreover, the intermolecular similarity of novel compounds was analyzed in the multidimensional space (mDS) of the structure/property-related in silico descriptors by means of principal component analysis (PCA) and hierarchical clustering analysis (HCA), respectively. The distance-oriented structure/property distribution was related with the experimental lipophilic data. Full article

Plasma proteins play a fundamental role in living organisms. They participate in the transport of endogenous and exogenous substances, especially drugs. 5-alkyl-12(H)-quino[3,4-b][1,4]benzothiazinium salts, have been synthesized as potential anticancer substances used for cancer treatment. Most anticancer substances generate a toxic effect on the human body. In order to check the toxicity and therapeutic dosage of these chemicals, the study of ligand binding to plasma proteins is very relevant. The present work presents the first comparative analysis of the binding of one of the 5-alkyl-12(H)-quino[3,4-b][1,4]benzothiazinium derivatives (Salt1) with human serum albumin (HSA), α-1-acid glycoprotein (AGP) and human gamma globulin (HGG), assessed using fluorescence, UV-Vis and CD spectroscopy. In order to mimic in vivo ligand–protein binding, control normal serum (CNS) was used. Based on the obtained data, the Salt1 binding sites in the tertiary structure of all plasma proteins and control normal serum were identified. Both the association constants (K_a) and the number of binding site classes (n) were calculated using the Klotz method. The strongest complex formed was Salt1–AGP_complex (K_a = 7.35·10⁴ and 7.86·10⁴ mol·L⁻¹ at excitation wavelengths λ_ex of 275 and 295 nm, respectively). Lower values were obtained for Salt1–HSA_complex (K_a = 2.45·10⁴ and 2.71·10⁴ mol·L⁻¹) and Salt1–HGG_complex (K_a = 1.41·10⁴ and 1.33·10⁴ mol·L⁻¹) at excitation wavelengths λ_ex of 275 and 295 nm, respectively, which is a positive phenomenon and contributes to the prolonged action of the drug. Salt1 probably binds to the HSA molecule in Sudlow sites I and II; for the remaining plasma proteins studied, only one binding site was observed. Moreover, using circular dichroism (CD), fluorescence and UV-Vis spectroscopy, no effect on the secondary and tertiary structures of proteins in the absence or presence of Salt1 has been demonstrated. Despite the fact that the conducted studies are basic, from the scientific point of view they are novel and encourage further in vitro and in vivo investigations. As a next part of the study (Part 2), the second new synthetized quinobenzothiazine derivative (Salt2) will be analyzed and published. Full article

The inverse correlation observed between Alzheimer’s disease (AD) and cancer has prompted us to look for cholinesterase-inhibiting activity in phenothiazine derivatives that possess anticancer properties. With the use of in silico and in vitro screening methods, our study found a new biological activity in anticancer polycyclic, tricyclic, and tetracyclic compounds. The virtual screening of a library of 120 ligands, which are the derivatives of azaphenothiazine, led to the identification of 25 compounds that can act as potential inhibitors of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). Biological assays revealed the presence of selective inhibitors of eeAChE (electric eel AChE) or eqBuChE (equine serum BuChE) and nonselective inhibitors of both enzymes among the tested compounds. Their potencies against eeAChE were in a submicromolar-to-micromolar range with IC₅₀ values from 0.78 to 19.32 μM, while their IC₅₀ values against eqBuChE ranged from 0.46 to 10.38 μM. The most potent among the compounds tested was the tetracyclic derivative, 6-(4-diethylaminobut-2-ynyl)-9-methylthioquinobenzothiazine 24, which was capable of inhibiting both enzymes. 9-Fluoro-6-(1-piperidylethyl)quinobenzothiazine 23 was found to act as a selective inhibitor of eqBuChE with an IC₅₀ value of 0.46 μM. Compounds with such a dual antitumor and cholinesterase-inhibitory activity can be considered as a valuable combination for the treatment of both cancer and AD prevention. The results presented in this study might open new directions of research on the group of tricyclic phenothiazine derivatives. Full article

A novel series of tetracyclic quinobenzothiazine derivatives was synthetized. Compounds containing a substituent (hydroxyl, methyl, phenyl, piperidyl, or piperazinyl) in positions 9 and 11 were obtained by cyclization of suitable 4-aminoquinolinium-3-thiolates. Quinobenzothiazine 10-O-substituted derivatives were obtained by alkylating the hydroxyl group in position 10 of the parent (quinobenzothiazine) system. Antiproliferative activity of the synthesized compounds was studied using cultured neoplastic cells (MDA-MB-231, SNB-19, and C-32 cell lines). Four selected compounds were investigated in more detail for cytotoxicity and antiproliferative effect. Transcriptional activity of genes regulating cell cycle (TP53), apoptosis (BAX, BCL-2), as well as proliferation (H3) were assessed. Finally, the ability of the selected compounds to bind DNA was checked in the presence of ethidium bromide. Full article