Margarita E. Neganova

Russian Academy of Sciences | RAS · Institute of Physiologically Active Substances

A simple method for modifying sesquiterpene lactones with 3,5-bis(arylidene)piperi-din-4-ones using the phase-transfer catalytic aza-Michael addition in the MeCN—K2CO3 system was developed. Molecular docking revealed that the synthesized conjugates of isoalantolactone, alantolactone, and dehydrocostus lactone with various bis(arylidene)-piperidones...

The era of chemotherapy began in the 1940s, which is the basis of traditional antitumor approaches and, being one of the most high-tech treatment methods, is still widely used to treat various types of cancer. A promising direction in modern medicinal chemistry is currently the creation of hybrid molecules containing several pharmacophore fragments...

A series of new isatin-3-hydrazones bearing different ammonium fragments was synthesized by a simple and easy work-up reaction of Girard’s reagents analogs with 1-(3,5-di-tert-butyl-4-hydroxybenzyl)isatin. All derivatives have been shown to have antioxidant properties. In terms of bactericidal activity against gram-positive bacteria, including meth...

Copper is an important metal micronutrient, required for the balanced growth and normal physiological functions of human organism. Copper-related toxicity and dysbalanced metabolism were associated with the disruption of intracellular respiration and the development of various diseases, including cancer. Notably, copper-induced cell death was defin...

A family of bifunctional dihetarylmethanes and dibenzoxanthenes is assembled via a reaction of acetals containing a 2-chloroacetamide moiety with phenols and related oxygen-containing heterocycles. These compounds demonstrated selective antitumor activity associated with the induction of cell apoptosis and inhibition of the process of glycolysis. I...

In recent years, researchers have often encountered the significance of the aberrant metabolism of tumor cells in the pathogenesis of malignant neoplasms. This phenomenon, known as the Warburg effect, provides a number of advantages in the survival of neoplastic cells, and its application is considered a potential strategy in the search for antitum...

Anticancer immune surveillance and immunotherapies trigger activation of cytotoxic cytokine signaling, including tumor necrosis factor-α (TNF-α) and TNF-related apoptosis-inducing ligand (TRAIL) pathways. The pro-inflammatory cytokine TNF-α may be secreted by stromal cells, tumor-associated macrophages, and by cancer cells, indicating a prominent r...

Background Gliomas and glioblastomas (GBM) are common primary malignant brain tumors, which are highly malignant and have a poor prognosis. The presence of cancer stem cells with unrestricted proliferative capacity and ability to generate glial neoplastic cells, the diffuse nature of GBM, and other specific factors of GBM contribute to poor results...

Here, we report the results of an investigation of the neuroprotective effects of securinine with tryptamine conjugate-allomargaritarine (2b), previously selected as the leading compound among a wide range of natural derivatives. 2b was synthesized from securinine using various Lewis acids as catalysts. In addition to the antioxidant and cytoprotec...

(READ full article https://onlinelibrary.wiley.com/share/author/Q9ZMTP3KX98XXVHXJJ2F?target=10.1111/php.13898) A series of tribenzo[g,l,q]-6H-1,4-diazepino[2,3-b]porphyrazines has been synthesized. A temperature-dependent steric effect was applied in the mixed Linstead macrocyclization of phthalonitrile and 5,7-bis(2′-arylethenyl)-6-propyl-6H-1,4-...

Multidrug resistance is the dominant obstacle to effective chemotherapy for malignant neoplasms. It is well known that neoplastic cells use a wide range of adaptive mechanisms to form and maintain resistance against antitumor agents, which makes it urgent to identify promising therapies to solve this problem. Hydroxamic acids are biologically activ...

A series of new fluorinated 1-benzylisatins was synthesized in high yields via a simple one-pot procedure in order to explore the possible effect of ortho-fluoro (3a), chloro (3b), or bis-fluoro (3d) substitution on the biological activity of this pharmacophore. Furthermore, the new isatins could be converted into water-soluble isatin-3-hydrazones...

Successful clinical methods for tumor elimination include a combination of surgical resection, radiotherapy, and chemotherapy. Radiotherapy is one of the crucial components of the cancer treatment regimens which allow to extend patient life expectancy. Current cutting-edge radiotherapy research is focused on the identification of methods that shoul...

Dear Colleagues, Neurological diseases are a diverse group of central and peripheral nervous system pathologies, which together are one of the leading causes of morbidity and mortality worldwide. To date, the range of treatment options for neuropathologies is extremely limited, with rates reflecting the number of FDA-approved drugs remaining low c...

The relationship between oncological pathologies and neurodegenerative disorders is extremely complex and is a topic of concern among a growing number of researchers around the world. In recent years, convincing scientific evidence has accumulated that indicates the contribution of a number of etiological factors and pathophysiological processes to...

The utility of sterically hindered phenols (SHPs) in drug design is based on their chameleonic ability to switch from an antioxidant that can protect healthy tissues to highly cytotoxic species that can target tumor cells. This work explores the biological activity of a family of 45 new hybrid molecules that combine SHPs equipped with an activating...

Dear Colleagues, Anti-cancer surveillance is one of the most important functions of the immune system as it helps to eliminate transformed and malfunctioning cells. However, many cancer cells manage to hide from the screening for elimination and/or survive the immune defense mechanisms. Cancer cell survival results in the development of resistance...

Novel monoterpene-based hydroxamic acids of two structural types were synthesized for the first time. The first type consisted of compounds with a hydroxamate group directly bound to acyclic, monocyclic and bicyclic monoterpene scaffolds. The second type included hydroxamic acids connected with the monoterpene moiety through aliphatic (hexa/heptame...

Four new palladium complexes containing a cyclometallated pinane ligand and l-amino acids (proline, tyrosine, serine, isoleucine) as coligands were synthesized and characterized. For the synthesis, we used the previously described binuclear palladacycle, the opening of the chloride bridges in which provides easy introduction of additional biogenic...

Combining two pharmacophores in a molecule can lead to useful synergistic effects. Herein, we show hybrid systems that combine sterically hindered phenols with dinitrobenzofuroxan fragments exhibit a broad range of biological activities. The modular assembly of such phenol/benzofuroxan hybrids allows variations in the phenol/benzofuroxan ratio. Int...

Parkinson’s disease is the second most common neurodegenerative disease. Unfortunately, there is still no definitive disease-modifying therapy. In our work, the antiparkinsonian potential of trans-epoxide (1S,2S,3R,4S,6R)-1-methyl-4-(prop-1-en-2-yl)-7-oxabicyclo [4.1.0]heptan-2,3-diol (E-diol) was analyzed in a rotenone-induced neurotoxicity model...

Six new chiral zinc(ii) complexes 1–6 based on ethylenediamine derivatives of terpenes were synthesized and characterized. The molecular structure of complex 2 was established by X-ray diffraction analysis. The modulating effect of complexes 1–6 on the functional state of mitochondria, which are organelles playing an utterly important role in maint...

We developed a microfluidic synthesis with UV-Vis diagnostics using a 3D printed chip for 8,13-disubstituted berberines. This system yielded up to 30% higher product yields with high antioxidant activity compared to traditional batch synthesis.

Using the methodology of “click” chemistry, a singular method has been developed for the synthesis of unique conjugates based on sesquiterpene lactones: dehydrocostuslactone and alantolactone with polyalkoxybenzenes. To expand the structural range of the resulting conjugates, the length of the 1,2,3-triazole spacer was varied. For all synthesized c...

A series of novel water-soluble salts of benzofuroxans was achieved via aromatic nucleophilic substitution reaction of 4,6-dichloro-5-nitrobenzofuroxan with various amines. The salts obtained showed good effectiveness of the pre-sowing treatment of seeds of agricultural crops at concentrations of 20–40 mmol. In some cases, the seed treatment with s...

Background Sesquiterpene lactones are secondary plant metabolites with a wide variety of biological activities. The process of lactone conjugation to other pharmacophores can increase the efficacy and specificity of the conjugated agent effect on molecular targets in various diseases, including brain pathologies. Derivatives of biogenic indoles, in...

Alzheimers disease (AD) is one of the most common neurodegenerative diseases in existence. It is characterized by an impaired cognitive function that is due to a progressive loss of neurons in the brain. Extracellular -amyloid (A) plaques are the main pathological features of the disease. In addition to abnormal protein aggregation, increased mitoc...

Using the methodology of “click” chemistry, a series of conjugates of 3,5-bis(benzylidene)-1-(prop-2-yn)piperidin-4-ones with 4-alkyl-3-azidomethyl-2-ethoxy-2,5-dihydro-5H-1,2 oxaphosphol 2-oxides was synthesized. All newly obtained compounds 8-18 were characterized by ¹H, ¹³C, ³¹P, ¹⁹F NMR and IR spectroscopy. The potential antitumor activity of t...

The treatment of central nervous system (CNS) malignancies, including brain cancers, is limited by a number of obstructions, including the blood-brain barrier (BBB), the heterogeneity and high invasiveness of tumors, the inaccessibility of tissues for early diagnosis and effective surgery, and anti-cancer drug resistance. Therapies employing nanome...

A method for modifying sesquiterpene lactones using the click chemistry methodology has been developed. A series of conjugates of alantolactone and dehydrocostus lactone with alkoxy substituted benzylazides was obtained and their cytotoxic profile with respect to tumor cells of the A549, SH-SY5Y, Hep-2 and HeLa lines was evaluated. It has been show...

Epigenetic regulation by microRNAs (miRs) demonstrated a promising therapeutic potential of these molecules to regulate genetic activity in different cancers, including colorectal cancers (CRCs). The RNA-based therapy does not change genetic codes in tumor cells but can silence oncogenes and/or reactivate inhibited tumor suppressor genes. In many c...

Chronic inflammation and oxidative stress are the interconnected pathological processes, which lead to cancer initiation and progression. The growing level of oxidative and inflammatory damage was shown to increase cancer severity and contribute to tumor spread. The overproduction of reactive oxygen species (ROS), which is associated with the reduc...

Hydroxamic acids are one of the most promising and actively studied classes of chemical compounds in medicinal chemistry. In this study, we describe the directed synthesis and effects of HDAC6 inhibitors. Fragments of adamantane and natural terpenes camphane and fenchane, combined with linkers of various nature with an amide group, were used as the...

Background The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) disease (COVID-19) triggers the development of numerous pathologies and infection-linked complications and exacerbates existing pathologies in nearly all body systems. Aside from the primarily targeted respiratory organs, adverse SARS-CoV-2 effects were observed in nervous,...

In the case of various pathologies, an imbalance between ROS generation and the endogenous AOS can be observed, which leads to excessive ROS accumulation, intensification of LPO processes, and oxidative stress. For the prevention of diseases associated with oxidative stress, drugs with antioxidant activity can be used. The cytotoxic, antioxidant, a...

New conjugates of daunorubicin with sesquiterpene lactones at the 3′‐amino group of anthracycline were synthesized and their effect on the viability of cell lines (HL60, Jurkat, K562, and A549) was assessed using a resazurin test. The effect on the cell cycle and apoptosis by flow cytometry was studied. The following natural lactones were used for...

The synthesis of new terpene ligands and palladium complexes based on them has been described. The stereoselective synthesis of new derivatives (-)-(1R,4S)-camphorquinone and N,N-dimethylethylenediamine (1 and 2) and palladium chelate complexes (3 and 4) based on them is presented. It was found that the direct cyclometallation of (1R,2R,3R,5R)-3-(b...

Alkaloids, secondary plant metabolites, are used in traditional medicine in many countries to treat various pathological conditions. Securinine, a unique indolizidine alkaloid combining four cycles, "6-azobicyclo[3.2.1]octane" as a key structure fused with α,β-unsaturated-γ-lactone and piperidine ring, has a broad spectrum of actions including anti...

Anthracycline antitumor antibiotics are one of the promising classes of chemotherapeutic agents for cancer treatment. The main deterrent to their use is high toxicity to a healthy environment, including cumulative cardiotoxicity. In our work, bipharmacophore molecules containing in their structure a fragment of the known anthracycline antibiotics d...

Hydroxamic acids are a promising class of chemical compounds with proven antitumor potential, primarily due to its ability to inhibit the activity of histone deacetylase enzymes. The analysis of modern experimental data shows a wide range of biological activity for hydroxamic acids, which makes them equally worthy candidates for the fight against n...

Drug development for the treatment of neurodegenerative diseases has to confront numerous problems occurring, in particular, because of attempts to address only one of the causes of the pathogenesis of neurological disorders. Recent advances in multitarget therapy research are gaining momentum by utilizing pharmacophores that simultaneously affect...

Epigenetic changes associated with histone modifications play an important role in the emergence and maintenance of the phenotype of various cancer types. In contrast to direct mutations in the main DNA sequence, these changes are reversible, which makes the development of inhibitors of enzymes of post-translational histone modifications one of the...

Cyclic hydroxamic acids based on quinazoline-4(3H)-one and dihydroquinazoline-4(1H)-one have been synthesized. The antioxidant and iron-chelating properties of these compounds, their effect on the activity of the histone deacetylase enzyme, and their cytotoxic effect on cells of various tumor lines have been investigated. We have identified two com...

Previously unknown conjugates of the natural sesquiterpene lactone arteannuin B, which was isolated from Artemisia annua, were synthesized via Michael reactions with pharmacophoric amines and tested in vitro for cytotoxic activity. The compounds were shown to exhibit antiproliferative properties for various tumor cell lines. The most active derivat...

Aims The main goal of this work where is to synthesize new original spirocyclic hydroxamic acids, investigate their cytotoxicity against to the panel of tumor cell lines and possible mechanism of action of these active compounds. Background Hydroxamic acids are one of the promising classes of chemical compounds with proven has anticancer potential...

This review focuses on pathogenesis of endometriosis, its possible biomarkers and role in endometriosis-associated ovarian cancer. We analyzed various databases to obtain new insights, theories, and biomarkers associated with endometriosis. There are several theories of endometriosis development and biomarker changes including atypical forms. A num...

Background The conjugates of the sesquiterpene lactone of the eremophilane series of 6-hydroxyxanthanodiene with hydrogenated azines (piperidines and piperazines) have been synthesized and identified by NMR spectrometer. Objective: A lactone with an unusual skeleton “6-hydroxyxanthanodiene” was extracted from the plant Elecampane (Inula helenium L)...

BACKGROUND Sleep disorders have emerged as potential cancer risk factors. OBJECTIVE This review discusses the relationships between sleep, obesity, and breathing disorders with concomitant risks of developing cancer. RESULTS Sleep disorders result in abnormal expression of clock genes, decreased immunity, and melatonin release disruption. Therefo...

Inflammatory gastrointestinal (GI) diseases and malignancies are associated with growing morbidity and cancer-related mortality worldwide. GI tumor and inflammatory cells contain activated sphingolipid-metabolizing enzymes, including sphingosine kinase 1 (SphK1) and SphK2, that generate sphingosine-1-phosphate (S1P), a highly bioactive compound. Ma...

Background and Purpose Sleep disorders have emerged as potential cancer risk factors. Objective This review discusses the relationships between sleep, obesity, and breathing disorders with concomitant risks of developing cancer. Results Sleep disorders result in an abnormal expression of clock genes, decreased immunity, and melatonin release disr...

Until recently, it was thought that there were no lymphatic vessels in the central nervous system (CNS). Therefore, all metabolic processes were assumed to take place only in the circulation of the cerebrospinal fluid (CSF) and through the blood-brain barrier’s (BBB), which regulate ion transport and ensure the functioning of the CNS. However, rece...

Objective: Glioblastoma is a highly aggressive and invasive brain and central nervous system (CNS) tumor. Current treatment options do not prolong overall survival significantly because the disease is highly prone to relapse. Therefore, research to find new therapies is of paramount importance. It has been discovered that glioblastomas contain a p...

Natural sesquiterpene lactones which contain an exocyclic methylene group in the β-position of the lactone ring react readily with N-nucleophiles. When studying the reaction of the natural epoxyalantolactone with the primary amines we demonstrate the formation of a new heterocyclic system—the hydrogenated benzo[g]furo[4,3,2-cd]indol-3(1H)-one. Spec...

Abstract To date, a lot of nanotechnological options are available for targeted drug delivery. Extracellular vesicles (EVs) are membrane structures that cells use for storage, transport, communication, and signaling. Recent research has focused on EVs as natural nanoparticles for drug delivery. This review sheds light on the application of EVs in c...

Abstract The use of nanoparticles dramatically increases the safety and efficacy of the most common anticancer drugs. The main advantages of nano-drugs and delivery systems based on nano-technology are effective targeting, delayed release, increased half-life, and less systemic toxicity. The use of nano-carriers has led to significant improvements...

Neuronal excitotoxicity which is induced by exposure to excessive extracellular glutamate is shown to be involved in neuronal cell death in acute brain injury and a number of neurological diseases. High concentration of glutamate induces calcium deregulation which results in mitochondrial calcium overload and mitochondrial depolarization that trigg...

Previously unknown conjugates of substituted piperazines with various functional groups on the N atom and the natural sesquiterpene lactones alantolactone, isoalantolactone, and alloalantolactone, the main constituents of the plant Inula helenium, were synthesized using Michael reaction. Cytotoxicity of the natural sesquiterpene lactones and their...

A series of stereospecific conjugates of the naturally occurring scaffold - alkaloid securinine 1 - was synthesized using the Lewis acid catalyst ytterbium triflate. The study of their antioxidant and cytoprotective properties showed that these compounds can be considered as potential neuroprotectors. Among these compounds, a leader substance is id...

The reaction of DL-valine hydroxamic acid with triacetonamine passes as N, N′-regioselective cyclocondensation to form (±) -1-hydroxy-3-isopropyl-7,7,9,9-tetramethyl-1,4,8-triazaspiro [4.5] decan-2-one. In vivo study of chemosensitizing antitumor activity of spirocyclic hydroxamic acid by the combination therapy with cytostatics of alkylating type...

Antioxidant activity of a pharmaceutical substance hypocard was compared with activity of nitromalic acid and well-known agents nicorandil and Mexidol. The ability of these substances to inhibit spontaneous and oxidant-induced LPO process in rat brain homogenate was analyzed. The mechanisms of these effects were studied. The antioxidant properties...