Stoyanka Atanasova Nikolova

Prof. Dr. Stoyanka Atanasova Nikolova

Plovdiv University, Plovdiv, Bulgaria
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Research Focus & Metrics

Academic Career Length

22Years (2005-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 July 2013 in Mini-Reviews in Medicinal Chemistry
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KBKuldipsinh P. Barot
Kuldipsinh P. Barot
Stoyanka Atanasova NikolovaStoyanka Atanasova Nikolova
Stoyanka Atanasova Nikolova
Iliyan IvanovIliyan Ivanov
Iliyan Ivanov
MGManjunath D. Ghate
Manjunath D. Ghate
Benzimidazole plays an important role in the medicinal chemistry and drug discovery with many pharmacological activities which have made an indispensable anchor for discovery of novel therapeutic agents. Substitution of benzimidazole nucleus is an important synthetic strategy in the drug discovery process. Therapeutic properties of the benzimidazole related drugs have encouraged the medicinal chemists to synthesize novel therapeutic agents. Therefore, it is required to couple the latest information with the earliest information to understand the current status of benzimidazole nucleus in drug discovery. In the present review, benzimidazole derivatives with different pharmacological activities are described on the basis of substitution pattern around the nucleus with an aim to help medicinal chemists for the development of SAR on benzimidazoles for each activity. This article aims to review the work reported, chemistry and pharmacological activities of benzimidazole derivatives during past years.

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Miglena MilushevaMiglena Milusheva
Miglena Milusheva
Vera Nikolaeva GledachevaVera Nikolaeva Gledacheva
Vera Nikolaeva Gledacheva
Iliyana Dimitrova StefanovaIliyana Dimitrova Stefanova
Iliyana Dimitrova Stefanova
Mehran Feizi-DehnayebiMehran Feizi-Dehnayebi
Mehran Feizi-Dehnayebi
RMRositsa Asenova Mihaylova
Rositsa Asenova Mihaylova
Stoyanka Atanasova NikolovaStoyanka Atanasova Nikolova
Stoyanka Atanasova Nikolova
The present article focuses on the synthesis and biological evaluation of a novel anthranilic acid hybrid and its diamides as antispasmodics. Methods: Due to the predicted in silico methods spasmolytic activity, we synthesized a hybrid molecule of anthranilic acid and 2-(3-chlorophenyl)ethylamine. The obtained hybrid was then applied in acylation with different acyl chlorides. Using in silico analysis, pharmacodynamic profiles of the compounds were predicted. A thorough biological evaluation of the compounds was conducted assessing their in vitro antimicrobial, cytotoxic, anti-inflammatory activity, and ex vivo spasmolytic activity. Density functional theory (DFT) calculation, including geometry optimization, molecular electrostatic potential (MEP) surface, and HOMO-LUMO analysis for the synthesized compounds was conducted using the B3LYP/6–311G(d,p) method to explore the electronic behavior, reactive regions, and stability and chemical reactivity of the compounds. Furthermore, molecular docking simulation along with viscosity measurement indicated that the newly synthesized compounds interact with DNA via groove binding mode. The obtained results from all the experiments demonstrate that the hybrid molecule and its diamides inherit spasmolytic, antimicrobial, and anti-inflammatory capabilities, making them excellent candidates for future medications.

4 August 2023 in Biomedicines
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Stoyanka Atanasova NikolovaStoyanka Atanasova Nikolova
Stoyanka Atanasova Nikolova
Miglena MilushevaMiglena Milusheva
Miglena Milusheva
Vera Nikolaeva GledachevaVera Nikolaeva Gledacheva
Vera Nikolaeva Gledacheva
Mehran Feizi-DehnayebiMehran Feizi-Dehnayebi
Mehran Feizi-Dehnayebi
LKLidia Kaynarova
Lidia Kaynarova
MTMina Todorova
Mina Todorova
Anticoagulants prevent the blood from developing the coagulation process, which is the primary cause of death in thromboembolic illnesses. Phenindione (PID) is a well-known anticoagulant that is rarely employed because it totally prevents coagulation, which can be a life-threatening complication. The goal of the current study is to synthesize drug-loaded Ag NPs to slow down the coagulation process. Methods: A rapid synthesis and stabilization of silver nanoparticles as drug-delivery systems for phenindione (PID) were applied for the first time. Results: Several methods are used to determine the size of the resulting Ag NPs. Additionally, the drug-release capabilities of Ag NPs were established. Density functional theory (DFT) calculations were performed for the first time to indicate the nature of the interaction between PID and nanostructures. DFT findings supported that galactose-loaded nanostructure could be a proper delivery system for phenindione. The drug-loaded Ag NPs were characterized in vitro for their antimicrobial, cytotoxic, and anticoagulant activities, and ex vivo for spasmolytic activity. The obtained data confirmed the drug-release experiments. Drug-loaded Ag NPs showed that prothrombin time (PT, sec) and activated partial thromboplastin time (APTT, sec) are approximately 1.5 times longer than the normal values, while PID itself stopped coagulation at all. This can make the PID-loaded Ag NPs better therapeutic anticoagulants. PID was compared to PID-loaded Ag NPs in antimicrobial, spasmolytic activity, and cytotoxicity. All the experiments confirmed the drug-release results.

11 October 2024 in Molecules
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Ghodsi Mohammadi ZiaraniGhodsi Mohammadi Ziarani
Ghodsi Mohammadi Ziarani
MRMahtab Rezakhani
Mahtab Rezakhani
Mehran Feizi-DehnayebiMehran Feizi-Dehnayebi
Mehran Feizi-Dehnayebi
Stoyanka Atanasova NikolovaStoyanka Atanasova Nikolova
Stoyanka Atanasova Nikolova
The surface of fumed silica nanoparticles was modified by pyridine carbaldehyde and barbituric acid to provide fumed-Si-Pr-Ald-Barb. The structure was identified and investigated through diverse techniques, such as FT-IR, EDX, Mapping, BET, XRD, SEM, and TGA. This nanocomposite was used to detect different cations and anions in a mixture of H2O:EtOH. The results showed that fumed-Si-Pr-Ald-Barb can selectively detect Hg2+ and Cr2O72− ions. The detection limits were calculated at about 5.4 × 10−3 M for Hg2+ and 3.3 × 10−3 M for Cr2O72− ions. A computational method (DFT) was applied to determine the active sites on the Pr-Ald-Barb for electrophilic and nucleophilic attacks. The HOMO-LUMO molecular orbital was calculated by B3LYP/6-311G(d,p)/LANL2DZ theoretical methods. The energy gap for the Pr-Ald-Barb and Pr-Ald-Barb+ion complexes was predicted by the EHOMO and ELUMO values. The DFT calculation confirms the suggested experimental mechanism for interacting the Pr-Ald-Barb with ions.

29 November 2023 in Pharmaceuticals
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Miglena MilushevaMiglena Milusheva
Miglena Milusheva
MTMina Todorova
Mina Todorova
Vera Nikolaeva GledachevaVera Nikolaeva Gledacheva
Vera Nikolaeva Gledacheva
Iliyana Dimitrova StefanovaIliyana Dimitrova Stefanova
Iliyana Dimitrova Stefanova
Mehran Feizi-DehnayebiMehran Feizi-Dehnayebi
Mehran Feizi-Dehnayebi
Stoyanka Atanasova NikolovaStoyanka Atanasova Nikolova
Stoyanka Atanasova Nikolova
Anti-inflammatory drugs are used to relieve pain, fever, and inflammation while protecting the cardiovascular system. However, the side effects of currently available medications have limited their usage. Due to these adverse effects, there is a significant need for new drugs. The current trend of research has shifted towards the synthesis of novel anthranilic acid hybrids as anti-inflammatory agents. Phenyl- or benzyl-substituted hybrids exerted very good anti-inflammatory effects in preventing albumin denaturation. To confirm their anti-inflammatory effects, additional ex vivo tests were conducted. These immunohistochemical studies explicated the same compounds with better anti-inflammatory potential. To determine the binding affinity and interaction mode, as well as to explain the anti-inflammatory activities, the molecular docking simulation of the compounds was investigated against human serum albumin. The biological evaluation of the compounds was completed, assessing their antimicrobial activity and spasmolytic effect. Based on the experimental data, we can conclude that a collection of novel hybrids was successfully synthesized, and they can be considered anti-inflammatory drug candidates—alternatives to current therapeutics.

30 May 2023 in Biomedicines
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MTMina Todorova
Mina Todorova
Miglena MilushevaMiglena Milusheva
Miglena Milusheva
LKLidia Kaynarova
Lidia Kaynarova
DGDeana Georgieva
Deana Georgieva
VDVassil Delchev
Vassil Delchev
Stoyanka Atanasova NikolovaStoyanka Atanasova Nikolova
Stoyanka Atanasova Nikolova
Chronic, multifactorial illnesses of the gastrointestinal tract include inflammatory bowel diseases. One of the greatest methods for regulated medicine administration in a particular region of inflammation is the nanoparticle system. Silver nanoparticles (Ag NPs) have been utilized as drug delivery systems in the pharmaceutical industry. The goal of the current study is to synthesize drug-loaded Ag NPs using a previously described 3-methyl-1-phenylbutan-2-amine, as a mebeverine precursor (MP). Methods: A green, galactose-assisted method for the rapid synthesis and stabilization of Ag NPs as a drug-delivery system is presented. Galactose was used as a reducing and capping agent forming a thin layer encasing the nanoparticles. Results: The structure, size distribution, zeta potential, surface charge, and the role of the capping agent of drug-loaded Ag NPs were discussed. The drug release of the MP-loaded Ag NPs was also investigated. The Ag NPs indicated a very good drug release between 80 and 85%. Based on the preliminary results, Ag NPs might be a promising medication delivery system for MP and a useful treatment option for inflammatory bowel disease. Therefore, future research into the potential medical applications of the produced Ag NPs is necessary.