Prediction of Degradation Profiles for Various Sartans under Solvent-Free Mechanochemical Conditions.

For the approval of a drug, the stability data must be submitted to regulatory authorities. Such analyses are often time-consuming and cost-intensive. Forced degradation studies are mainly carried out under harsh conditions in the dissolved state, often leading to extraneous degradation profiles for a solid drug. Oxidative mechanochemical degradation offers the possibility of generating realistic degradation profiles. In this study, a sustainable mechanochemical procedure is presented for the degradation of five active pharmaceutical ingredients (APIs) from the sartan family: losartan potassium, irbesartan, valsartan, olmesartan medoxomil, and telmisartan. High-resolution mass spectrometry enabled the detection of impurities already present in untreated APIs and allowed the elucidation of degradation products. Significant degradation profiles could already be obtained after 15-60 min of ball milling time. Many of the identified degradation products are described in the literature and pharmacopoeias, emphasizing the significance of our results and the applicability of this approach to predict degradation profiles for drugs in the solid state.

Telmisartan loaded lipid nanocarrier as a potential repurposing approach to treat glioma: characterization, apoptosis evaluation in U87MG cells, pharmacokinetic and molecular simulation study.

The study explores anticancer potential of telmisartan (TS) loaded lipid nanocarriers (TLNs) in glioma cells as a potential repurposing nanomodality along with estimation of drug availability at rat brain. Experimental TLNs were produced by previously reported method and characterized.In vitroanticancer efficacy of experimental TLNs was estimated by MTT, confocal microscopy, and FACs analysis in glioma cells. Plasma and brain pharmacokinetic (PK) parameters were also analysed by LCMS/MS. Spherical, nanosized, homogenous, unilamellar, TLNs were reported having desirable drug loading (9.5% ± 0.6%), negative zeta potential and sustained TS release tendency. FITC-TLNs were sufficiently internalized into U87MG cells line within 0.5 h incubation period. IC50for TLNs was considerably higher than free TS in the tested glioma cell lines. Further, TLNs induced superior apoptotic effect in U87MG cells than TS. PK (plasma/brain) data depicted higher AUC,Vss, MRT with lower Cltfor TLNs suggesting improved bioavailability,in vivoresidence and sustained drug availability than free TS administration. Docking studies rationalizedin vitro/in vivoresults as preferably higher binding affinity (docking score:12.4) was detected for TS with glioma proteins. Further,in vivostudies in glioma bearing xenograft model is underway for futuristic clinical validation of TLNs.

Increasing Drug Loading of Weakly Acidic Telmisartan in Amorphous Solid Dispersions through pH Modification during Hot-Melt Extrusion.

Oral drug therapy requiring large quantities of active pharmaceutical ingredients (APIs) can cause a substantial pill burden, which can increase nonadherence and worsen healthcare outcomes. Maximizing the drug loading of APIs in oral dosage forms is essential to reduce pill burden. This can be challenging for poorly water-soluble APIs without compromising performance. We show a promising strategy for maximizing the drug loading of pH-dependent APIs in amorphous solid dispersions (ASDs) produced by hot-melt extrusion (HME) without compromising their dissolution performance. We examine potential increases in the drug loading (w/w) of telmisartan in ASDs by incorporating bases to modify pH during HME. Telmisartan is a weakly acidic, poorly water-soluble API with pH-dependent solubility. It is practically insoluble at physiological pH, but its solubility increases exponentially at pH values above 10. Telmisartan was extruded with the polymer Soluplus and various bases. With no base, the maximum drug loading achieved by extrusion was only 5% before crystalline telmisartan was detected. Including a strong, water-soluble base (NaOH or KOH) increased the maximum amorphous drug loading to 50%. These results indicate that telmisartan has pH-dependent solubility in a molten polymer, similar to that in an aqueous solution. We also examine the stability of Soluplus when extruded with a strong base, using solid-state nuclear magnetic resonance (ssNMR) to determine that NaOH (but not KOH) causes degradation by hydrolysis. Supersaturation was maintained for at least 20 h during dissolution testing of a 50% telmisartan ASD in biorelevant media.

A Simple UPLC/MS-MS Method for Simultaneous Determination of Lenvatinib and Telmisartan in Rat Plasma, and Its Application to Pharmacokinetic Drug-Drug Interaction Study.

Lenvatinib is a multi-targeted tyrosine kinase inhibitor that inhibits tumor angiogenesis, but hypertension is the most common adverse reaction. Telmisartan is an angiotensin receptor blocker used to treat hypertension. In this study, a simple ultra-performance liquid chromatography-tandem mass spectrometry method was developed for the simultaneous determination of lenvatinib and telmisartan, and it was applied to the pharmacokinetic drug interaction study. Plasma samples were treated with acetonitrile to precipitate protein. Water (containing 5 mM of ammonium acetate and 0.1% formic acid) and acetonitrile (0.1% formic acid) were used as the mobile phases to separate the analytes with gradient elution using a column XSelect HSS T3 (2.1 mm × 100 mm, 2.5 µm). Multiple reaction monitoring in the positive ion mode was used for quantification. The method was validated and the precision, accuracy, matrix effect, recovery, and stability of this method were reasonable. The determination of analytes was not interfered with by other substances in the blank plasma, and the calibration curves of lenvatinib and telmisartan were linear within the range of 0.2-1000 ng/mL and 0.1-500 ng/mL, respectively. The results indicate that lenvatinib decreased the systemic exposure of telmisartan. Potential drug interactions were observed between lenvatinib and telmisartan.

Preparation and Evaluation of Co-amorphous Formulations of Telmisartan-Amino Acids as a Potential Method for Solubility and Dissolution Enhancement.

Telmisartan (TLM) is a potent antihypertensive drug with pH-dependent aqueous solubility. This work aimed to enhance the solubility and dissolution rate of TLM by the co-amorphous drug amino acid (AA) approach by combining TLM, with different types and ratios of AAs. The co-amorphous TLM-AA blends were prepared by freeze-drying and investigated for solid-state characteristics like the dissolution rate enhancement of TLM. Among the prepared co-amorphous formulations, TLM-arginine (ARG) exhibited the greatest enhancement in solubility with increasing the molar ratio of ARG. The TLM-ARG at 1:2 ratio showed about a 57-fold increase in solubility of TLM and the highest dissolution percentage in phosphate buffer (pH7.5) (100% in 20 minutes) compared to both crystalline TLM (20% in 60 min) and physical mixture. Powder XRD, DSC, FTIR analysis and SEM demonstrated the formation of amorphous form within the co-amorphous formulations. Only TLM:ARG (1:0.5) were stable at (40°C, 75% RH) for a minimum of 90 days. In conclusion, ARG was able to stabilize the amorphous form of TLM and enhances its aqueous solubility and dissolution. The 1:2 w/w ratio of TLM-ARG co-amorphous showed the best solubility and dissolution rate while the 1:0.5 w/w ratio showed the best stability.

Re-usage of the Waste Drug as Molecular Chemosensor for Fe3+ Ion: Application towards Fluorescent Ink.

Herein, a novel notion is used to reuse an expired drug namely Telmisartan (Sensor 2) to optically sense the Fe3+ metal ion. Direct re-usage of the drug avoided wearisome procedures of synthesis, hence proved the method as simple and economic. Sensor 2 found highly stable in the temperature range 25-75 °C. Relative fluorescence was almost the same even after 35 days of observation. There were no significant changes in wavelength even after adding different concentrations of FeCl3, which shows the high stability of the compound. The value of Limit of Detection (LOD) observed was 34.2 nM. FTIR studies confirmed the presence of carboxylic group. The method of fluorescence quenching was used to detect the Fe3+ ion. The association between Sensor 2 and Fe3+ was analyzed using Benesi-Hildebrand relation. Positive deviation from the linearity of S-V plots suggested that the quenching was not purely dynamic. Further, this deviation was analyzed by the sphere of action quenching model. To investigate whether the quenching is diffusion limited, we applied the finite sink approximation model and deduced that quenching is due to both static and dynamic processes. Due to the high fluorescence property of the molecule, it was successfully tested to be used as fluorescent ink.

QbD-based development of an extraction procedure for simultaneous quantification of telmisartan, amlodipine besylate and chlorthalidone in combination complex matrix formulation.

The main objective of this study was to establish an efficient extraction procedure for the estimation of telmisartan, amlodipine and chlorthalidone from their combination in sample matrix using an analytical quality by design approach. Initial screening studies were performed for optimization of a suitable diluent to extract active components from sample matrix. Further, the same study was extended for the identification of critical method attributes and the factors affecting the analytical target profile. This study also explains the rugged and robust quantitative determination of combinations drugs with a shorter run time. The design of experimental studies confirms that the current center point parameters are well suited to recoveries. The chromatographic separation was achieved with an X-Terra RP8, 150 × 4.6 mm, 3.5 µm column with an isocratic mobile phase (mixture of 20 mm aqueous ammonium acetate and acetonitrile). To demonstrate the stability-indicating nature of the optimized method, forced degradation studies were conducted and proved. The optimized method was validated according to International Conference on Harmonization guidelines.

Synthesis of Telmisartan Organotin(IV) Complexes and their use as Carbon Dioxide Capture Media.

Novel, porous, highly aromatic organotin(IV) frameworks were successfully synthesized by the condensation of telmisartan and an appropriate tin(IV) chloride. The structures of the synthesized organotin(IV) complexes were elucidated by elemental analysis, 1H-, 13C-, and 119Sn-NMR, and FTIR spectroscopy. The surface morphologies of the complexes were inspected by field emission scanning electron microscopy. The synthesized mesoporous organotin(IV) complexes have a Brunauer-Emmett-Teller (BET) surface area of 32.3-130.4 m2·g-1, pore volume of 0.046-0.162 cm3·g-1, and pore size of around 2.4 nm. The tin complexes containing a butyl substituent were more efficient as carbon dioxide storage media than the complexes containing a phenyl substituent. The dibutyltin(IV) complex had the highest BET surface area (SBET = 130.357 m2·g-1), the largest volume (0.162 cm3·g-1), and was the most efficient for carbon dioxide storage (7.1 wt%) at a controlled temperature (323 K) and pressure (50 bars).

Photostabilization of Poly(vinyl chloride) by Organotin(IV) Compounds against Photodegradation.

Poly(vinyl chloride) (PVC), a polymer widely used in common household and industrial materials, undergoes photodegradation upon ultraviolet irradiation, leading to undesirable physicochemical properties and a reduced lifetime. In this study, four telmisartan organotin(IV) compounds were tested as photostabilizers against photodegradation. PVC films (40-µm thickness) containing these compounds (0.5 wt%) were irradiated with ultraviolet light at room temperature for up to 300 h. Changes in various polymeric parameters, including the growth of hydroxyl, carbonyl, and alkene functional groups, weight loss, reduction in molecular weight, and appearance of surface irregularities, were investigated to test the efficiency of the photostabilizers. The changes were more noticeable in the blank PVC film than in the films containing the telmisartan organotin(IV) compounds. These results reflect that these compounds effectively inhibit the photodegradation of PVC, possibly by acting as hydrogen chloride and radical scavengers, peroxide decomposers, and primary photostabilizers. The synthesized organotin(IV) complexes could be used as PVC additives to enhance photostability.

Cu-Mediated Amination of (Hetero)Aryl C-H bonds with NH Azaheterocycles.

Direct synthesis of N-(hetero)arylated heteroarenes has been realized through Cu-mediated C-N coupling of NH azaheterocycles with aryl C-H bonds under aerobic conditions. This method features a broad scope of both heterocyclic arenes (pyridine, quinoline, pyrazole, imidazole, furan, thiophene, benzofuran, and indole) and NH azaheterocycles (imidazole, pyrazole, indole, azindole, purine, indazole, benzimidazole, pyridone, carbazole), providing a versatile method for the synthesis of pharmaceutically important N-(hetero)arylated heteroarenes. The versatility of this reaction was further demonstrated through late-stage modification of marketed drugs and the synthesis of a key intermediate for accessing a class of angiotensin II receptor 1 antagonists.

In Vitro Dissolution as a Tool for Formulation Selection: Telmisartan Two-Step IVIVC.

The purpose of this investigation was to develop an exploratory two-step level A IVIVC for three telmisartan oral immediate release formulations, the reference product Micardis, and two generic formulations (X1 and X2). Correlation was validated with a third test formulation, Y1. Experimental solubility and permeability data were obtained to confirm that telmisartan is a class II compound under the Biopharmaceutic Classification System. Bioequivalence (BE) studies plasma profiles were combined using a previously published reference scaling procedure. X2 demonstrated in vivo BE, while X1 and Y1 failed to show BE due to the lower boundary of the 90% confidence interval for Cmax being outside the acceptance limits. Average plasma profiles were deconvoluted by the Loo-Riegelman method to obtain the oral fractions absorbed ( fa). Fractions dissolved ( fdiss) were obtained in several conditions in USP II and USP IV apparatus, and later, the results were compared in order to find the most biopredictive model, calculating the f2 similarity factor. The apparatus and conditions showing the same rank order than in vivo data were selected for further refinement of conditions. A Levy plot was constructed to estimate the time scaling factor and to make both processes, dissolution and absorption, superimposable. The in vitro dissolution experiment that reflected more accurately the in vivo behavior of the different formulations of telmisartan employed the USP IV dissolution apparatus and a dissolution environment with a flow rate of 8 mL/min and a three-step pH change, from 1.2 to 4.5 and 6.8, with a 0.05% of Tween 80. Thus, these conditions gave rise to a biopredictive dissolution test. This new model is able to predict the formulation differences in dissolution that were previously observed in vivo, which could be used as a risk-analysis tool for formulation selection in future bioequivalence trials.

Tablet Formulation of a Polymeric Solid Dispersion Containing Amorphous Alkalinized Telmisartan.

To overcome the poor dissolution of telmisartan (TMS) at weak acidic pH, amorphous alkalinized TMS (AAT) was prepared by introducing sodium hydroxide as a selective alkalizer. AAT-containing polymeric solid dispersions were prepared by a solvent evaporation method; these solid dispersions were AAT-PEG, AAT-PVP, AAT-POL, and AAT-SOL for the polymers of PEG 6000, PVP K30, Poloxamer 407, and Soluplus, respectively. The characteristics of the different formulations were observed by differential scanning calorimetry, powder X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy. To compare the supersaturation behavior, a dissolution test was performed at 37 ± 0.5 °C either in 900 ml (plain condition) or 500 ml (limited condition) of pH 6.8-simulated intestinal fluid used as a medium. AAT-SOL exhibited enhanced dissolution, indicating the probability of extended supersaturation in the limited condition. AAT-SOL was further formulated into a tablet by introducing other excipients, Vivapur 105 and Croscarmellose, as a binder and superdisintegrant, respectively, using a direct compression method. The selected AAT-SOL tablet was superior to Micardis (the reference product) in the aspect of supersaturation maintenance during dissolution in the limited condition, suggesting that it is a promising candidate for practical development that can replace the commercial product in the future.

Development of L-Lysine Amino Acid-Based Co-Crystal of Telmisartan Using Crystal Engineering Approach to Improve Solubility, Dissolution, and Micrometric Properties.

AIM: To develop a co-crytsal of Telmisartan for enhancing its solubility in water. BACKGROUND: Intermolecular interaction happens in crystal packing; it utilizes and helps to understand the design of new solid with their respective chemical and physical properties called crystal engineering. It is a blueprint of molecular solids with specific chemical and physical properties through an understanding and handling of intermolecular interaction for increasing the solubility, in case of poor water-soluble drugs. OBJECTIVES: The study was taken under consideration with an aim to generate and synthesize a cocrystal form of Telmisartan (TEL) with L-lysine to improve its water solubility, dissolution, and micrometric properties. METHODS: Using dry grinding technique, solvent evaporation and cooling crystallization, the results revealed a generation of co-crystals with enhanced solubility by liquid drop grinding method. Hence, this process was further explored to investigate various formulations and process parameters that could significantly affect the crystal solubility, dissolution, and micrometric properties. RESULTS: The solubility of TEL co-crystals was enhanced by L-lysine. Further, the optimized batch was subjected to its micrometric evaluation and physiochemical characterization like FT-IR, NMR, PXRD. The result of the micrometric evaluation showed better results as compared to standards. The dissolution studies also showed a better dissolution rate for TEL co-crystal tablets than TEL tablets formulation. CONCLUSION: Co-crystals of TEL with L-lysine showed better solubility and dissolution rate.

Revealing new therapeutic opportunities in hypertension through network-driven integrative genetic analysis and drug target prediction approach.

Epidemiological studies have established that untreated hypertension (HTN) is a major independent risk factor for developing cardiovascular diseases (CVD), stroke, renal failure, and other conditions. Several important studies have been published to prevent and manage HTN; however, antihypertensive agents' optimal choice remains controversial. Therefore, the present study is undertaken to update our knowledge in the primary treatment of HTN, specifically in the setting of other three important diseases. MicroRNAs (miRNAs) are remarkably stable short endogenous conserved non-coding RNAs that bind to the mRNA at its (3' UTR) to regulate its gene expression by causing translational repression or mRNA degradation. Through their coordinated activities on different pathways and networks, individual miRNAs control normal and pathological cellular processes. Therefore, to identify the critical miRNA-mRNA-TF interactions, we performed systematic bioinformatics analysis. We have also employed the molecular modelling and docking approach to identify the therapeutic target that delivers novel empathies into Food and Drug Administration approved and herbal drug response physiology. Gene Expression Omnibus (GEO) was employed to identify the differentially expressed genes (DEGs) and hub genes- KNG1, HLA-DPB1, CXCL8, IL1B, and BCL2. The HTN associated feed-forward loop (FFL) network included miR-9-5p, KNG1 and AR. We employed high throughput screening to get the best interacting compounds, telmisartan and limonin, that provided a significant docking score (-13.3 and -12.0 kcal/mol) and a potential protective effect that may help to combat the impact of HTN. The present study provides novel insight into HTN etiology through the identification of mRNAs and miRNAs and associated pathways.

Zinc complexation improves angiotensin II receptor type 1 blockade and in vivo antihypertensive activity of telmisartan.

Background: Angiotensin II receptor blockers were designed as therapeutic agents to block the binding site of the angiotensin II receptor type 1 (AT1R). Methodology: The structure of telmisartan was modified by coordination to the biometal Zn(II), resulting in the compound ZnTelm. Its antihypertensive activity and cellular mechanisms in comparison to telmisartan were studied. Results: Compared with telmisartan, ZnTelm displayed stronger binding to AT1R (binding studies on AT1R-transfected human embryonic kidney cells) and a greater reduction of reactive oxygen species and cytosolic calcium concentration induced by angiotensin II. The antihypertensive activity of the complex (assessed in an N(G)-Nitro-L-arginine methyl ester-induced hypertension model) was significantly higher. ZnTelm also reduced hypertrophy in aortic artery rings and tubular collagen deposition. Conclusion: ZnTelm enhances the AT1R blockade and consequently its antihypertensive effect.

Hydrophilic polymer driven crystallization self-assembly: an inflammatory multi-drug combination nanosystem against Alzheimer's disease.

The hydrophobic polymer driven crystallization of self-assembled micelles is usually sufficient for their purposes in materials chemistry studies. However, with the state of smart drug delivery research, micelles alone are not enough. The principles of the self assembly driven by hydrophilic dextran brushes together with charged poly(3-acrylamidophenyl boronic acid) (PPBA) are uncovered in this study. A series of poly(ε-caprolactone)-block-poly(3-acrylamidophenyl boronic acid)-dextran (PCL-b-PPBA-Dex) micelles and vesicles are investigated as potential Alzheimer's disease (AD) treatments. Three inflammatory microenvironment responsive micelles, including celecoxib drug-loaded micelles (CEL), ibuprofen drug-loaded micelles (IBU) and telmisartan drug-loaded micelles (TEL), are developed. In vivo, CEL/IBU (mixture of CEL and IBU) and CEL/TEL (mixture of CEL and TEL) suppress the activation of glia and reduce the levels of inflammatory mediators through eliminating cyclooxygenase 2 (COX-2) signals. The CEL/TEL combination nanosystem is better at correcting neuroinflammation and improving the spatial memory ability of a senescence-accelerated mouse prone 8 model (SAMP8). We consider that the inflammation responsive combination nanosystem provides a new potential treatment for AD clinical patients.

Tackling resistance in chronic myeloid leukemia: Novel cell death modulators with improved efficacy.

The development of resistance poses a serious problem in the therapy of cancer due to the necessity of a multiple-drug and unlimited treatment of affected patients. In chronic myeloid leukemia (CML), the introduction of imatinib has revolutionized the therapy. The persistence of an untreatable cancer stem cell pool and other resistance-causing factors, however, also impede the cure of this malignancy. New therapeutic approaches are therefore essential to overcome current treatment drawbacks. In this regard, an intervention in the STAT5 signaling pathway can significantly improve drug response, as this central signaling node induces the formation of highly resistant CML cells. In the present study, we continued the design of efficient chemosensitizers derived from the partial PPARγ agonist telmisartan. The developed 2-carbonitriles or 2-carboxymethyl esters showed improved potency in sensitizing K562-resistant cells to imatinib treatment, even at concentrations, which are considered patient-relevant. At 5 µM, for instance, 2d sensitized the cells in such a manner that the resistance was fully overcome and the recovered efficacy of imatinib resulted in >76% cell death. Importantly, all compounds were non-cytotoxic per se. A transactivation experiment showed that only the carbonitriles are partial agonists of PPARγ, which does not seem to be involved in the mode of action. Yet, immunoassays revealed a suppression of the STAT5 phosphorylation status by co-application of the most active derivatives with imatinib. This mechanism consequently resulted in reduced cell proliferation and induction of cell death in resistant CML cells.

Utilization of a fattigation platform gelatin-oleic acid sodium salt conjugate as a novel solubilizing adjuvant for poorly water-soluble drugs via self-assembly and nanonization.

Solubilizing adjuvants are commonly used to dissolve insoluble drugs by simply adding in a formulation. In this study, gelatin and oleic acid sodium salt (OAS), a generally recognized as safe-listed material were chosen and conjugated to develop a natural solubilizing adjuvant using the fattigation platform technology to enhance solubility and dissolution rate of poorly water-soluble drugs according to self-assembly and nanonization principle when simply mixed with poorly water-soluble drugs. We synthesized the gelatin and OAS conjugates (GOC) at three different ratios (1:1, 1:3, 1:5; GOC 1, GOC 2, and GOC 3, respectively) via the 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide/N-hydroxysuccinimide reaction using a spray dryer. This amphiphilic micronized GOC was self-assembled into nanoparticles. The synthesis of new amphiphilic conjugates was identified through Fourier transform-infrared (FT-IR) spectroscopy. The powder properties of the GOCs, such as angle of repose, bulk density, and tapped density were varied with the oleic acid bonding ratio. Then, GOCs were utilized to investigate the enhanced solubility and release rate of various poorly water-soluble drugs such as cilostazol (CSZ), coenzyme Q10, ticagrelor, telmisartan, aprepitant and itraconazole as model drugs. Based on the solubility studies by concentration and type of GOCs, 3% GOC 2 was selected. When this GOC was mixed with these model drugs by the physical mixing, wetting and hot melting methoods, the solubility was highly enhanced compared to the pure control drug, ranging from 20 to 150,000 times. In case of CSZ, all formulations were significantly improved release rate compared to the of CSZ alone and the reference tablet, cilostan® (Korea United Pharm) in simulated intestinal fluid containing 0.2% sodium lauryl sulfate. Differential scanning calorimetry and powder X-ray diffraction were conducted to confirm the crystal polymorphic structure of CSZ, and as a result they changed to diminutive peak intensity compared to CSZ alone. Field-emission scanning electron microscopy indicated that GOC was round with a reduced size of about 100 nm. The reduction of drug particles via nanonization and self-assembly of amphiphilic GOC in an aqueous media could be a key factor to improve poor water solubility by providing a favorable dispersion of drug molecules in an amphiphilic network.

Antioxidant Activity of Telmisartan-Cu(II) Nanoparticles Connected 2-Pyrimidinamine and Their Evaluation of Cytotoxicity Activities.

Copper nanoparticles (Cu-Nps) are one of the promising materials for the advancement of nanoscience and technology. In this work, we synthesized telmisartan copper nanoparticles and 2-pyrimidinamines via Biginelli reaction using telmisartan copper nanoparticles (Cu-Nps) as a reusable catalyst. The synthesis of 2-pyrimidinamine derivatives (1a-c) was achieved in water and under solvent-free condition (Green chemistry approach). Synthesis of 2-pyrimidinamine with telmisartan copper nanoparticle (Cu-Nps-Pyr) unexpected product was also isolated from synthesis of 2-pyrimidinamine preparation. Antioxidant and cytotoxic activities were carried out both in 2-pyrimidinamine (1a-1c) and 2-pyrimidinamine with telmisartan copper nanoparticles (Cu-Nps-Pyr). The synthesized 2-pyrimidinamine derivatives (1a-c) were characterized from FT-IR, 1H and 13C NMR spectroscopy, mass and elemental analyses. The synthesized telmisartan copper nanoparticles (Cu-Nps) were characterized from UV spectroscopy, XRD, SEM, EDX, AFM (atomic force microscopy), profile, waviness, and roughness analyses. Antioxidant activity was screened based on ABTS·+ radical scavenging and linoleic acid peroxidation performance. Cu-Nps-Pyr-1b showed substantial antioxidant (97.2%) activity against ABTS·+ assay and 91.2% activity against AAPH assays compared with Trolox. Cytotoxicity was evaluated using HepG2, HeLa, and MCF-7 cell lines, the Cu-Nps-Pyr-1a is high in toxicities (GI50 = 0.01 µm) against the HeLa cancel cell line compared with doxorubicin. The developed copper NPs with 2-pyrimidinamine (Cu-Nps-Pyr) could provide promising advances as antioxidant activities; this nanocomposition could be considered an anticancer treatment in future investigations.

Identification and development of non-cytotoxic cell death modulators: Impact of sartans and derivatives on PPARγ activation and on growth of imatinib-resistant chronic myelogenous leukemia cells.

4'-((2-Propyl-1H-benzo[d]imidazol-1-yl)methyl)-[1,1'-biphenyl]-2-carboxylic acid derived from telmisartan was identified as lead for the design of cell death modulators. In this study, we evaluated the efficacy of telmisartan itself and other sartans in combination with imatinib against K562-resistant cells. The findings were directly used to further optimize the lead structure. Telmisartan and candesartan cilexetil represented the most effective sartans, thus the influence of carboxyl/methyl carboxylate groups at positions 7 (compounds 6, 7) or 4 (compounds 12-14) at the benzimidazole core was studied. Additionally, according to the results of a former structure-activity study, telmisartan was transformed to the related amide (1). Telmisartan amide 1, as well as the esters 6 and 12 markedly sensitized the resistant CML cells to imatinib treatment. Correlation with their potency to activate PPARγ is not given. Candesartan cilexetil, telmisartan and 1 showed the profile of partial agonists at PPARγ with EC50 values of 4.2, 4.3 and 9.1 µM, respectively, while 6 and 12 caused only marginal intrinsic activation at 10 µM (Amax = 22% and 13%). However, the repression of the STAT5 phosphorylation relates with the possibility to sensitize K562-resistant CML cells to imatinib treatment. It is worth mentioning that all compounds were per se non-cytotoxic at relevant concentrations.