New conjugates of amiridine and salicylic derivatives (salicylamide, salicylimine, and salicylamine) with different lengths of alkylene spacers were designed, synthesized, and evaluated as potential multifunctional central nervous system therapeutic agents for Alzheimer's disease (AD). Conjugates demonstrated high acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibition (IC: AChE, 0.265-4.
View Article and Find Full Text PDFA series of 2-arylhydrazinylidene-3-oxo acids (AHOAs) was prepared by dealkylation of alkyl-2-arylhydrazinylidene-3-oxo-3-alkanoates with AlBr. Using X-Ray, NMR spectroscopy, and quantum mechanical calculations (QM), the existence of AHOAs in a thermodynamically favorable Z-form stabilized by two intramolecular H-bonds was established. All AHOAs had acceptable ADME parameters.
View Article and Find Full Text PDFA large series of 2-arylchromen-4-ones containing from 1 to 3 fluorine atoms or a trifluoromethyl group in the structure was synthesized by condensation of fluorinated 2-hydroxyacetophenones with benzaldehydes in an alkaline medium and subsequent oxidative cyclization of the resulting 2'-hydroxychalcones by action of I in DMSO. The cytotoxicity of the obtained compounds was studied in glioblastoma cell line, SNB19, and in a monkey-derived normal kidney epithelium cell line, Vero. In addition, antiglycation activity of the obtained compounds was evaluated.
View Article and Find Full Text PDFEffective therapeutics for Alzheimer's disease (AD) are in great demand worldwide. In our previous work, we responded to this need by synthesizing novel drug candidates consisting of 4-amino-2,3-polymethylenequinolines conjugated with butylated hydroxytoluene via fixed-length alkylimine or alkylamine linkers (spacers) and studying their bioactivities pertaining to AD treatment. Here, we report significant extensions of these studies, including the use of variable-length spacers and more detailed biological characterizations.
View Article and Find Full Text PDFNew amiridine-thiouracil conjugates with different substituents in the pyrimidine fragment (R = CH , CF Н, CF , (CF ) H) and different spacer lengths (n = 1-3) were synthesized. The conjugates rather weakly inhibit acetylcholinesterase (AChE) and exhibit high inhibitory activity (IC up to 0.752 ± 0.
View Article and Find Full Text PDFWe investigated the inhibitory activities of novel 9-phosphoryl-9,10-dihydroacridines and 9-phosphorylacridines against acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and carboxylesterase (CES). We also studied the abilities of the new compounds to interfere with the self-aggregation of β-amyloid (Aβ) in the thioflavin test as well as their antioxidant activities in the ABTS and FRAP assays. We used molecular docking, molecular dynamics simulations, and quantum-chemical calculations to explain experimental results.
View Article and Find Full Text PDFThe L-type calcium current (I) is the first step in cardiac excitation-contraction-coupling and plays an important role in regulating contractility, but also in electrical and mechanical remodeling. Primary culture of cardiomyocytes, a widely used tool in cardiac ion channel research, is associated with substantial morphological, functional and electrical changes some of which may be prevented by electrical pacing. We therefore investigated I directly after cell isolation and after 24 h of primary culture with and without regular pacing at 1 and 3 Hz in rat left ventricular myocytes.
View Article and Find Full Text PDFA series of previously synthesized conjugates of tacrine and salicylamide was extended by varying the structure of the salicylamide fragment and using salicylic aldehyde to synthesize salicylimine derivatives. The hybrids exhibited broad-spectrum biological activity. All new conjugates were potent inhibitors of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) with selectivity toward BChE.
View Article and Find Full Text PDF4-Arylhydrazinylidene-5-(polyfluoroalkyl)pyrazol-3-ones (4-AHPs) were found to be obtained by the regiospecific cyclization of 2-arylhydrazinylidene-3-(polyfluoroalkyl)-3-oxoesters with hydrazines, by the azo coupling of 4-nonsubstituted pyrazol-5-oles with aryldiazonium chlorides or by the firstly discovered acid-promoted self-condensation of 2-arylhydrazinylidene-3-oxoesters. All the 4-AHPs had an acceptable ADME profile. Varying the substituents in 4-AHPs promoted the switching or combining of their biological activity.
View Article and Find Full Text PDFOne of the powerful antioxidants used clinically is Edaravone (EDA). We synthesized a series of new EDA analogs, 4-aminopyrazol-5-ol hydrochlorides, including polyfluoroalkyl derivatives, via the reduction of 4-hydroxyiminopyrazol-5-ones. The primary antioxidant activity of the compounds in comparison with EDA was investigated in vitro using ABTS, FRAP, and ORAC tests.
View Article and Find Full Text PDFThe development of multi-target-directed ligands (MTDLs) would provide effective therapy of neurodegenerative diseases (ND) with complex and nonclear pathogenesis. A promising method to create such potential drugs is combining neuroactive pharmacophoric groups acting on different biotargets involved in the pathogenesis of ND. We developed a synthetic algorithm for the conjugation of indole derivatives and methylene blue (), which are pharmacophoric ligands that act on the key stages of pathogenesis.
View Article and Find Full Text PDFAlzheimer's disease (AD) is considered a modern epidemic because of its increasing prevalence worldwide and serious medico-social consequences, including the economic burden of treatment and patient care. The development of new effective therapeutic agents for AD is one of the most urgent and challenging tasks. To address this need, we used an aminoalkylene linker to combine the well-known anticholinesterase drug tacrine with antioxidant 2-tolylhydrazinylidene-1,3-diketones to create 3 groups of hybrid compounds as new multifunctional agents with the potential for AD treatment.
View Article and Find Full Text PDFPhosphorylated adenosine derivatives are important biological molecules with diverse biological functions connected with the energetic balance of the cell, biosynthesis of cell components and regulation of protein activity. Measurement of these compounds provides information about the cell signalling in the body as well as the quantity of microorganisms in the environment. Surface-enhanced Raman spectroscopy (SERS) is an optical method that provides a unique spectrum of a substance at low concentrations.
View Article and Find Full Text PDFBiosensors combining the ultrahigh sensitivity of surface-enhanced Raman scattering (SERS) and the specificity of nucleic acid aptamers have recently drawn attention in the detection of respiratory viruses. The most sensitive SERS-based aptasensors allow determining as low as 10 virus particles per mL that is 100-fold lower than any antibody-based lateral flow tests but 10-100-times higher than a routine polymerase chain reaction with reversed transcription (RT-PCR). Sensitivity of RT-PCR has not been achieved in SERS-based aptasensors despite the usage of sophisticated SERS-active substrates.
View Article and Find Full Text PDFSyringomyelia (SM) with Chiari malformation is a rare disease with an unpredictable course. Surgery and other interventions help reduce the severity of symptoms, but over 50% patients require re-operation. Auto-resolution is rare in this type of SM, and most cases progress to complications, which may amount to a great burden.
View Article and Find Full Text PDFNew conjugates of tacrine and salicylamide with alkylene spacers were synthesized and evaluated as potential multifunctional agents for Alzheimer's disease (AD). The compounds exhibited high acetylcholinesterase (AChE, IC to 0.224 μM) and butyrylcholinesterase (BChE, IC to 0.
View Article and Find Full Text PDFUsing two ways of functionalizing amiridine-acylation with chloroacetic acid chloride and reaction with thiophosgene-we have synthesized new homobivalent bis-amiridines joined by two different spacers-bis--acyl-alkylene () and bis--thiourea-alkylene () -as potential multifunctional agents for the treatment of Alzheimer's disease (AD). All compounds exhibited high inhibitory activity against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) with selectivity for BChE. These new agents displayed negligible carboxylesterase inhibition, suggesting a probable lack of untoward drug-drug interactions arising from hydrolytic biotransformation.
View Article and Find Full Text PDFA new series of conjugates of aminoadamantane and γ-carboline, which are basic scaffolds of the known neuroactive agents, memantine and dimebon (Latrepirdine) was synthesized and characterized. Conjugates act simultaneously on several biological structures and processes involved in the pathogenesis of Alzheimer's disease and some other neurodegenerative disorders. In particular, these compounds inhibit enzymes of the cholinesterase family, exhibiting higher inhibitory activity against butyrylcholinesterase (BChE), but having almost no effect on the activity of carboxylesterase (anti-target).
View Article and Find Full Text PDFDuring the COVID-19 pandemic, the development of sensitive and rapid techniques for detection of viruses have become vital. Surface-enhanced Raman scattering (SERS) is an appropriate tool for new techniques due to its high sensitivity. SERS materials modified with short-structured oligonucleotides (DNA aptamers) provide specificity for SERS biosensors.
View Article and Find Full Text PDFWe synthesized eleven new amiridine-piperazine hybrids 5a-j and 7 as potential multifunctional agents for Alzheimer's disease (AD) treatment by reacting N-chloroacetylamiridine with piperazines. The compounds displayed mixed-type reversible inhibition of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). Conjugates were moderate inhibitors of equine and human BChE with negligible fluctuation in anti-BChE activity, whereas anti-AChE activity was substantially dependent on N4-substitution of the piperazine ring.
View Article and Find Full Text PDFAn expanded series of alkyl 2-arylhydrazinylidene-3-oxo-3-polyfluoroalkylpropionates (HOPs) 3 was obtained via Cu(OAc)-catalyzed azo coupling. All were nanomolar inhibitors of carboxylesterase (CES), while moderate or weak inhibitors of acetylcholinesterase and butyrylcholinesterase. Steady-state kinetics studies showed that HOPs 3 are mixed type inhibitors of the three esterases.
View Article and Find Full Text PDFNew hybrids of 4-amino-2,3-polymethylenequinoline with different sizes of the aliphatic ring linked to butylated hydroxytoluene (BHT) by enaminoalkyl () or aminoalkyl () spacers were synthesized as potential multifunctional agents for Alzheimer's disease (AD) treatment. All compounds were potent inhibitors of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) with selectivity toward BChE. Lead compound , 2,6-di--butyl-4-{[2-(7,8,9,10- tetrahydro-6H-cyclohepta[b]quinolin-11-ylamino)-ethylimino]-methyl}-phenol exhibited an IC(AChE) = 1.
View Article and Find Full Text PDF4-Nitroso-3-trifluoromethyl-5-alkyl[(het)aryl]pyrazoles were synthesized via one-pot nitrosation of 1,3-diketones or their lithium salts followed by treatment of hydrazines. Reduction of nitroso-derivatives made it possible to obtain 4-amino-3-trifluoromethylpyrazoles chlorides. According to computer-aided calculations, all synthesized compounds are expected to have acceptable ADME profile for drug design.
View Article and Find Full Text PDFMolecules
August 2020
New hybrid compounds of 4-amino-2,3-polymethylene-quinoline containing different sizes of the aliphatic ring and linked to -tolylsulfonamide with alkylene spacers of increasing length were synthesized as potential drugs for treatment of Alzheimer's disease (AD). All compounds were potent inhibitors of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) with selectivity toward BChE. The lead compound 4-methyl-N-(5-(1,2,3,4-tetrahydro-acridin-9-ylamino)-pentyl)-benzenesulfonamide () exhibited an IC (AChE) = 0.
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