ИСТИНА

Целью проекта является разработка общей методологии синтеза новых функциональных производных титаноцен дихлорида, обладающих большей устойчивостью в физиологических условиях и большей биодоступностью при сохранении высокой цитотоксичности по отношению к клеточным линиям злокачественных новообразований.

According to the World Health Organization (WHO), cancer is holding one of the first places in terms of total mortality (up to 10 million deaths in 2020), and the dynamics of morbidity in 2022 is still positive [https://www.who.int/news-room/fact-sheets/detail/cancer]. The search for new antitumor drugs is an important trend in modern medicinal chemistry. According to 2017th year data [Sun J. et al. A systematic analysis of FDA-approved anticancer drugs. // BMC Syst. Biol. – 2017. –V. 11. –I. S5. –P. 87 27–43.], the US Food and Drug Administration (FDA) has registered 150 anticancer drugs, and about 2/3 of them have been approved within the last two decades. However, the basis of chemotherapy of cancer today is still platinum cytotoxic drugs. Despite the high cytotoxicity on tumor cells, the therapeutic use of platinum anticancer drugs is associated with the inevitable development of a number of severe side effects associated with the abiogenicity of platinum and its accumulation in the patient's body, which, together with the rapid development of resistance of cancer cells to platinum drugs, in many cases reduces positive effect of chemotherapy to zero. The solution to this problem can be found in the field of the rational design and synthesis of new cytotoxic coordination compounds of biogenic transition metals, which have a lower overall toxicity and leave the body more easily, but comparable to platinum drugs in terms of IC50 values. Titanocene dichloride is a promising coordination compound for modification in order to obtain agents for the treatment of cancer, since it has a number of advantages: 1) Titanium is a biogenic element normally present in the human body in an amount of up to 9 mg (or 0.07 mg per liter of blood) [https://microelements.ru/elements/Ti.pdf] and has a low general toxicity. And although the biological functions of titanium in the body of mammals have not yet been established, there are studies showing the possibility of their existence in various species of living beings [Zierden M. R. et al. Contemplating a role for titanium in organisms // Metallomics. – 2016. – V. 8. –I. 1. – P. 9–16.]. 2) The end product of the hydrolysis of titanocene dichloride and its derivatives is titanium dioxide - a completely biocompatible, non-toxic and non-immune response material widely used in medicine [Jafari S. et al. Biomedical Applications of TiO2 Nanostructures: Recent Advances. // Int. J. Nanomedicine. – 2020. – V.15. – P. 3447-3470.]. 3) Titanocene dichloride has a pronounced cytotoxicity against various cell lines of malignant neoplasms [Köpf H. et al. Titanocene dichloride – the first metallocene with cancerostatic activity // Angew. Chem. Int. Ed. – 1979 – V. 18.– P. 477–478.] and successfully completed preclinical trials as a drug for the treatment of breast adenocarcinoma. Past in 1993 - 2000, the first and second stages of clinical trials [Kröger N. et al. Phase II Clinical Trial of Titanocene Dichloride in Patients with Metastatic Breast Cancer. // Onkologie. – 2000. – V. 23. – P. 60–62.] showed high tolerated doses in patients (up to 240 mg/m2). 4) The key disadvantage of titanocene dichloride as a therapeutic agent for use in vivo is low stability in aqueous media and rapid hydrolysis, leading to the loss of ligands, can be eliminated by replacing labile chloride anions with more inert ligands, in particular carboxylate anions [Saturnino C. et al. New titanocene derivatives with high antiproliferative activity against breast cancer cells. // Bioorg. Med. Chem. Lett. – 2014.– V. 24.– I. 1.– P. 136-140.]. 5) The mechanism of the cytotoxic action of titanocene dichloride is largely similar to the mechanism of the cytotoxic action of cisplatin [Olszewski U. et al. Mechanisms of Cytotoxicity of Anticancer Titanocenes. // Anticancer Agents Med. Chem. – 2010. – V. 10. – I.4. – P. 302-311.], which means that the existing findings in the design of functional ligands, optimal lipophilicity values, etc. obtained during the study of second and third generation platinum drugs can be used to create more potent therapeutic agents based on titanocene. Within the framework of this project, it is planned to develop a universal methodology for obtaining new functional derivatives of titanocene dichloride by replacing chloride anions with carboxylate-containing organic ligands of various nature to obtain symmetrical and unsymmetrical coordination compounds. On the basis of literature data, the most promising ligands were chosen: 1) derivatives of 2-(5-oxo-2-thioxoimidazol-1-yl)acetic acid – they have their own cytotoxicity in free form and in complexes with various transition metals [Krasnovskaya O. et al. Novel copper-containing cytotoxic agents based on 2-thioxoimidazolones. // J. Med. Chem.– 2020. –V. 63. –I. 21. –P. 13031–13063.]; 2) natural and non-natural amino acids - increase the water solubility and bioavailability of coordination compounds, including titanocene derivatives [Klapoetke T. M. et al. Synthesis, Characterization, and Structural Investigation of the First Bioinorganic Titanocene (IV) alpha-Amino Acid Complexes Prepared from the Antitumor Agent Titanocene Dichloride. // Organometallics. – 1994.–V. 13.–I. 9.–P. 3628–3633.]; 3) non-steroidal anti-inflammatory drugs (NSAIDs) - lead to the localization of platinum coordination compounds in the nucleus and mitochondria, demonstrate a synergistic increase in the cytotoxicity of Pt + NSAIDs [Krasnovskaya O. et al. Alternative mechanism of action of the DNP Pt IV prodrug: intracellular cisplatin release and the mitochondria-mediated apoptotic pathway. // Dalton Trans. – 2021. – V. 50. – P. 7922-7927.]; 4) fluorescent dyes based on fluorescein, BODIPY, naphthalimide are suitable for visualizing the distribution of coordination compounds and obtaining theranostic agents. The scientific novelty of this study lies in: 1) in the development of previously unknown synthetic approaches to asymmetric titanocene derivatives containing two different ligands of different chemical nature; 2) in the creation of a universal (general) methodology for the synthesis and obtaining a library of new, undescribed, stable in aqueous media titanocene dichloride derivatives with cytotoxic activity, with NSAIDs, derivatives of 2-(5-oxo-2-thioxoimidazol-1-yl)acetic acid and fluorescent dyes as ligands; 3) in a comprehensive study of the physicochemical and biological properties of the functional derivatives of titanocene obtained for the first time; 4) in the establishing of structure-cytotoxic activity patterns for the described library of compounds useful for further research of new cytotoxic coordination compounds based on titanocene.

В рамках данного проекта планируется получение библиотеки новых функциональных производных титаноцен дихлорида на основе карбоксилат-содержащих органических лигандов, обладающих большей гидролитической устойчивостью, большей, по сравнению с титаноцен дихлоридом, биодоступностью и более низкими величинами IC50 по отношению к клеткам злокачественных новообразований, способных в перспективе конкурировать с препаратами платины, составляющими основу современной цитотоксической терапии, но лишенные их фундаментальных недостатков. Для полученных функциональных производных будут установлены закономерности структура – цитотоксическая активность и выбраны соединения лидеры, наиболее перспективные для дальнейших In Vitro и In Vivo исследований противоопухолевых свойств по сумме факторов (стабильность в физиологических условиях, внутриклеточное проникновение и накопление, цитотоксичностьи т.д.). Для соединений лидеров будут проведены дополнительные биологические испытания in vitro для установления механизма цитотоксического действия. Финальным результатом проекта станут новые производные титаноцена с перспективой применения в качестве терапевтических, диагностических и тераностических агентов, для которых будут разработаны надежные, препаративные и масштабируемые методики синтеза.

За последние три года была проведена работа по синтезу координационных соединений биогенных переходных металлов с высокой цитотоксической активностью, в частности замещенных ферроценов. Полученные результаты были опубликованы в ряде статей в высокорейтинговых рецензируемых научных изданиях: 1. D. A. Guk, O. O. Krasnovskaya, A. A. Moiseeva, V. Tafeenko, N. Ul’yanovskii, D. Kosyakov, V. I. Pergushov, M. Y. Melnikov, N. Zyk, D. A. Skvortsov, E. Lopatukhina, A. N. Vaneev, P. Gorelkin, A. Erofeev, A. Majouga, and E. K. Beloglazkina. New fe-cu bimetallic coordination compounds based on ω-ferrocene carboxylic acids and 2-thioimidazol-4-ones: structural, mechanistic and biological studies. INORGANIC CHEMISTRY FRONTIERS, 8:4730–4750, 2021. DOI: 10.1039/D1QI00714A 2. O. Krasnovskaya, D. A. Guk, A. Naumov, V. N. Nikitina, A. Semkina, K. Y. Vlasova, V. Pokrovsky, O. O. Ryabaya, S. Karshieva, D. A. Skvortsov, I. Zhirkina, R. R. Shafikov, P. Gorelkin, A. Vaneev, A. Erofeev, D. Mazur, V. A. Tafeenko, V. I. Pergushov, M. Melnikov, M. A. Soldatov, V. V. Shapovalov, A. V. Soldatov, R. Akasov, V. Gerasimov, D. A. Sakharov, A. A. Moiseeva, N. V. Zyk, E. K. Beloglazkina, and A. G. Majouga. Novel copper-containing cytotoxic agents based on 2-thioxoimidazolones. Journal of Medicinal Chemistry, 63(21):acs.jmedchem.0c01196, 2020. DOI: 10.1021/acs.jmedchem.0c01196