L.N. Gumilyov Eurasian National University, a dissertation defense for the degree of Doctor of Philosophy (PhD) by Zhanakov Mukhtar on the topic «Synthesis and Properties of New Heterocyclic Compounds Based on Functional Derivatives of Benzofuroxans» to the educational program «8D05306 – Chemistry».
The dissertation was carried out at the «Chemistry education department» of L.N. Gumilyov Eurasian National University.
The language of defense is kazakh
Official reviewers:
Dyusebayeva Moldir Akimzhanovna, a dean of faculty of chemistry and chemical technology at al-Farabi Kazakh National University, Cand.Chem.Sci.
Ibataev Zharkyn Abykenovich, a Head of the Department of Physics and Chemistry of S. Seifullin Kazakh Agrotechnical Research University, Cand.Chem.Sci., assoc. professor.
Temporary members of the Dissertation Committee:
Festa Aleksey Alekseevich, a Senior Lecturer, Department of Organic Chemistry, P. Lumumba Peoples' Friendship University of Russia, Cand.Chem.Sci., senior researche, Moscow, Russia.
Yu Valentina Konstantinovna, a Head of the Laboratory of Chemistry of Synthetic and Natural Drugs at A.B. Bekturov Institute of Chemical Sciences, Dr.Chem.Sci., Professor, Almaty, Republic of Kazakhstan.
Fazylov Serik Drakhmetovich, a Chief Researcher at Institute of Organic Synthesis and Coal Chemistry of the Republic of Kazakhstan, Dr.Chem.Sci., Professor, Karaganda, Republic of Kazakhstan.
Scientific advisors:
Zhatkanbayeva Zhanna Kalanbekovna – Professor of the Department of Chemistry, L.N. Gumilyov Eurasian National University, Cand.Chem.Sci., Professor
Chugunova Elena Alexandrovna– Leading Researcher of the A.E. Arbuzov Institute of Organic and Physical Chemistry, Dr.Chem.Sci. (Kazan, Russia).
The defense will take place on November 28, 2025, at 03:00 PM in the Dissertation Council for the training direction «8D053 – Physical and chemical sciences» in the specialty «8D05306 – Chemistry» of L.N. Gumilyov Eurasian National University. The defense meeting is planned to be held online.
Link: https://rb.gy/4na6ba
Address: Астана қ., Қ. Сәтпаев к-сі, 2, Л.Н. Гумилев ат. ЕҰУ оқу-әкімшілік (бас) корпус, 302 аудитория
Abstract (English): ANNOTATION On the dissertation of Zhanakov Mukhtar Nurlanovich on the topic “Synthesis and Properties of New Heterocyclic Compounds Based on Functional Derivatives of Benzofuroxans”, submitted for the degree of Doctor of Philosophy (PhD) in the educational program 8D05306-Chemistry The relevance of the dissertation work and its level of development. In the field of modern organic and medicinal chemistry, particular attention is paid to the development of new heterocyclic compounds with biological activity. A key focus here is the search for and synthesis of structures possessing antitumor, antimicrobial, and antioxidant effects, driven by the global need for new effective pharmaceuticals and biologically active molecules. Of special interest is the class of N-oxides of nitrogen-containing heterocycles, which demonstrate a broad spectrum of chemical transformations, making them valuable as synthetic intermediates, catalysts, and oxidizers. Among these, 1,2,5-oxadiazole-2-oxides (furoxans) and their condensed analogs – benzofuroxans – hold a prominent place. These structures are capable of releasing nitric oxide (NO), which possesses diverse biological functions, including the regulation of vascular tone, immune response, and apoptosis of tumor cells. It is this property that has generated significant interest among researchers in benzofuroxan derivatives as promising NO donors in pharmaceutical chemistry. Over recent decades, a substantial body of evidence has accumulated in global literature confirming the biological potential of furoxans and benzofuroxans. Approaches have been developed to obtain "hybrid" molecules in which the benzofuroxan fragment is combined with other pharmacophoric groups. Such structures demonstrate a synergistic effect, enhancing cytotoxic activity against various tumor cell lines, as well as exhibiting pronounced antibacterial properties. Nevertheless, many benzofuroxan derivatives are limited by low water solubility, which significantly reduces their practical value in the development of drug formulations and biological preparations. Addressing this issue through the preparation of water-soluble salts and complex compounds is an urgent scientific task. In scientific practice, a significant portion of research is focused on fundamental aspects of the reactivity of benzofuroxans and their derivatives. At the same time, comprehensive studies integrating organic synthesis, structural identification, and systematic biological evaluation (in vitro and in vivo) remain limited. Particularly underdeveloped are directions related to the creation of hybrid structures based on benzofuroxans and sterically hindered phenols (SHPs), which possess their own antioxidant and antimicrobial properties. The combination of these pharmacophoric systems opens new perspectives in the design of compounds with targeted action. The current state of research on the topic reveals several gaps. Despite the existence of individual publications on synthetic approaches to benzofuroxans, there is a lack of systematic studies aimed at their comprehensive modification to obtain water-soluble forms of benzofuroxan derivatives and to investigate biological activity across a broad range of models. There is also insufficient data on the mechanisms of action of benzofuroxan hybrids at the molecular level, including the induction of apoptosis, generation of reactive oxygen species, etc. This work is devoted to the synthesis, study of reactivity, and modification possibilities of benzofuroxan derivatives to obtain new biologically active compounds with antitumor, antimicrobial, and plant growth-regulating properties. The research implements a comprehensive approach to creating hybrid sterically-hindered phenol/benzofuroxan structures and water-soluble salts of benzofuroxan derivatives with a terminal tertiary amino group. The study is interdisciplinary, combining methods of organic synthesis, physicochemical analysis, and bioassay. The aim of the dissertation research is the synthesis, modification, and study of the reactivity of functional benzofuroxan derivatives to obtain new biologically active compounds, including hybrid sterically hindered phenol/benzofuroxan structures and water-soluble salts with a terminal tertiary amino group, followed by a comprehensive investigation of their biological activity. Research Objectives: 1. Development of synthetic methods for novel antitumor compounds based on reactions of 7-chloro-4,6-dinitrobenzofuroxan with sterically hindered phenols containing phosphonamide fragments. 2. Synthesis of new water-soluble salts of benzofuroxan derivatives via reactions of 4,6-dichloro-5-nitrobenzofuroxan with N,N-diamines. 3. Investigation of spontaneous reduction processes of benzofuroxans to benzofurazans involving terminal tertiary amino groups. 4. Comprehensive study of the biomedical activity of the obtained compounds, including antimicrobial properties, cytotoxic and hemolytic effects in vitro, in vivo toxicity, as well as evaluation of their application potential in agriculture and water management. Research Methods. The dissertation used the following modern physicochemical methods: IR, NMR 1H, 13C, 31P spectroscopy, as well as two-dimensional NMR spectroscopy, mass spectrometry, elemental and X-ray structural analysis, thin-layer, preparative, and column chromatography, and quantum-chemical calculations. Research Objects. Benzofuroxan, N,N-diamines, and sterically hindered phenols containing phosphonamide fragments. Subject of Research. The synthesis of new water-soluble salts based on benzofuroxan derivatives, the creation of hybrid structures containing sterically hindered phenol and benzofuroxan fragments, confirmation of their composition using modern physicochemical methods, optimization of synthesis methods, and investigation of their biological activity. Main Thesis Statements to be Defended: 1. A novel series of sterically hindered phenols (SHPs) containing benzofuroxan fragments has been synthesized for the first time via aromatic nucleophilic substitution reaction of 7-chloro-4,6-dinitrobenzofuroxan; the influence of molar ratio of reagents on product composition has been determined, and biological activity of the obtained compounds has been revealed. 2. A new series of water-soluble benzofuroxan salts has been obtained for the first time through reactions of 4,6-dichloro-5-nitrobenzofuroxan with amines; it has been established that certain compounds demonstrate cytotoxic activity and possess biocidal properties. 3. The possibility of reducing benzofuroxans to benzofurazans through interaction with diamines has been demonstrated for the first time; the reaction mechanism has been determined through quantum chemical calculations and fully confirmed by experimental data. Main Research Results and Justification of Novelty: 1. A novel series of sterically hindered phenols (SHPs) containing benzofuroxan fragments has been synthesized via aromatic nucleophilic substitution reaction of 7-chloro-4,6-dinitrobenzofuroxan. It has been demonstrated that varying the molar ratio of reagents (2:1 or 1:1) enables targeted synthesis of products with different compositions. 2. Hybrid SHP/benzofuroxan compounds have been established to exhibit high cytotoxic activity against HuTu 80, MCF-7, and HeLa cell lines (IC₅₀ = 0.9-5.9 μM). Compound 7,7'-((3-((3,5-Di-tert-butyl-4-hydroxyphenyl) (diphenoxyphosphoryl) methyl)pyridine-2,6-diyl)bis(azanediyl))bis(4,6-dinitrobenzo[c][1,2,5]oxadiazol 1-oxide) (5d) demonstrated higher selectivity compared to doxorubicin and sorafenib. The cytotoxicity is associated with induction of mitochondrial apoptosis and generation of reactive oxygen species. 3. Antimicrobial activity of hybrid compounds has been revealed to occur only when the SHP molecule contains at least two benzofuroxan fragments. 4. Novel water-soluble benzofuroxan salts have been synthesized for the first time through reactions of 4,6-dichloro-5-nitrobenzofuroxan with aromatic, aliphatic, and heterocyclic amines. 5. Benzofuroxans have been shown to undergo reduction to benzofurazans upon interaction with diamines. The reaction mechanisms have been confirmed by quantum chemical calculations and are consistent with experimental data, explaining the impossibility of further reduction of aminobenzofuroxan derivatives due to high activation barriers. 6. Water-soluble salts containing morpholine and N-dimethylpropylamine fragments demonstrated high cytotoxic activity correlating with glycolytic inhibition capability. Compounds chloride 6-chloro-4-(3-(morpholin-4-yl)propylamino)-5-nitrobenzo[c][1,2,5]oxadiazole 1-oxide chloride (9e) and chloride 6-chloro-4-(3-(dimethylammonio)propylamino)-5-nitrobenzo[c][1,2,5]oxadiazole 1-oxide (9g) have been selected for further investigation. 7. In vivo studies showed compound 9e to be less toxic (LD₅₀ = 22.0 ± 1.33 mg/kg) compared to compound 9g (LD₅₀ = 13.75 ± 1.73 mg/kg), and at doses of 1.25-5 mg/kg it increased the lifespan of mice with P388 leukemia by 20-28%. 8. Synthesis conditions for benzofuroxan derivatives (temperature, time, reagent ratios, solvent and catalyst selection) have been optimized, enabling production of active compounds in increased quantities. Compound 9g has been shown to increase wheat and sugar sorghum yields by 10.7-26% (3.4-15 q/ha). 9. Morpholine benzofuroxan chloride 6-chloro-4-(2-(morpholin-4-ium)ethylamino)-5-nitrobenzo[c]oxadiazole 1-oxide (9d) demonstrated activity against both aerobic and anaerobic bacteria and is considered a promising candidate for use as a biocidal or biostatic agent in industrial wastewater treatment. Theoretical and practical significance of this work lies in expanding the understanding of benzofuroxan reactivity and their transformation into benzofurazans, establishing structure-activity relationships, and elucidating the mechanisms of biological activity of hybrid derivatives. The developed synthetic methodologies have enabled the production of compounds with confirmed antitumor and antimicrobial activity (both in vitro and in vivo), opening prospects for further pharmacological research. Additionally, water-soluble salts and hybrid structures have demonstrated application potential in agriculture as plant growth promoters and microbiota regulators, as well as in water treatment as biocidal agents for wastewater purification. Compliance of the dissertation with the directions of scientific development and state programs. The dissertation work was carried out within the framework of grant funding from the Science Committee of the Ministry of Science and Higher Education of the Republic of Kazakhstan No. AP19677249 and the program of the Ministry of Agriculture of the Republic of Kazakhstan No. BR10764960, as well as with the support of the Russian Science Foundation and the Cabinet of Ministers of the Republic of Tatarstan under scientific project No. 22-23-20015. Publications: The main content of the dissertation is presented in 4 publications with impact factors and indexed by the WES database (Russian Journal of General Chemistry, International Journal of Molecular sciences, Pharmaceuticals and Chemical Bulletin of Kazakh National University and 2 abstracts of conference reports. The main results of the dissertation work were published with impact factor, international peer-reviewed journals and conference proceedings: Description of the doctoral student's contribution to the preparation of each publication. Description of the doctoral student's contribution to each publication. The doctoral student directly participated in obtaining experimental data, processing, and interpreting experimental results for the preparation of the article "Diverse Biological Activity of Benzofuroxan/Sterically Hindered Phenols Hybrids" as a co-author, published in the journal "Pharmaceuticals" 2023, 16, 499 (https://doi.org/10.3390/ph16040499). At the time of its publication in 2023, the journal "Pharmaceuticals" had an Impact Factor for 2021 of 5.2, and a quartile in Chemistry, Medicinal - Q2. The doctoral student directly participated in obtaining, processing, and interpreting experimental data for the article "Water-Soluble Salts Based on Benzofuroxan Derivatives – Synthesis and Biological Activity" as a co-author, published in the journal IJMS 2022, 23, 14902 (https://doi.org/10.3390/ijms232314902). At the time of its publication in 2022, the journal had an Impact Factor for 2021 of 6.2, and a quartile in Biochemistry - Q1, in Chemistry, Multidisciplinary - Q2. It had a CiteScore for 2021 of 6.9, with a percentile in Organic Chemistry - 80. The doctoral student, as the first author, directly participated in collecting experimental data, their processing, and interpreting experimental results related to the preparation of the article "Unusual Reduction of Benzofuroxans to Benzofurazans with the Participation of the Terminal Amino Group" published in the journal Russian Journal of General Chemistry 2023, 93(S2), S491–S500 (https://doi.org/10.1134/S1070363223150112). At the time of its publication in 2023, the journal had an Impact Factor for 2022 of 0.9, and a quartile in Chemistry, Multidisciplinary - Q4. It had a CiteScore for 2022 of 1.4, and a percentile in General Chemistry - 28. The doctoral student, as the first author, directly participated in literature collection, data processing, and preparation of the review article "Mini-review: Advances in the Synthesis and Biological Activity of Benzofuroxan and Furoxan Derivatives" in the journal Chemical Bulletin of KazNU 2025, 114, S22-S-37 (https://doi.org/10.15328/cb1391). At the time of its publication in 2025, the journal had an Impact Factor for 2023 of 0.3, and a quartile in Chemistry, Multidisciplinary - Q4. The doctoral student directly participated in obtaining experimental data, processing, and interpreting experimental results for the preparation of materials and abstracts of 2 presentations at international scientific conferences: «Молекулярный дизайн биологически активных веществ: биохимические и медицинские аспекты» dedicated to the 120th anniversary of the birth of Academician B.A. Arbuzov (Russia, Kazan, 2023), as well as at the International Scientific and Practical Conference «Фитосанитарная безопасность: угрозы и пути решения» (Kazakhstan, Almaty, 2023). Volume and Structure of the Dissertation: The dissertation comprises 137 pages and includes 33 tables and 86 figures in addition to the main text. The work consists of an introduction, three main chapters, a conclusion, and a list of references containing 239 sources.
Conclusion of the Research Ethics Committee
Defense of the dissertation: https://www.youtube.com/watch?v=UtoiezOgMJA
