New palladium complexes based on myrtenal and benzylamine derivatives: Selectivity of cyclometalation, antitumor activity

• Published in: Inorganica Chimica Acta 2024-02, Vol.576, p.122457, Article 122457
• Main Authors: Zalevskaya, O.A., Gur’eva, Y.A., Kutchin, A.V., Aleksandrova, Yu.R., Pukhov, S.A., Nikolaeva, N.S., Neganova, M.E.
• Format: Article
• Language: English
• Subjects: Antitumor activity; Apoptosis induction; Benzylamine; Cyclometallation; Migration activity; Myrtenal; Palladium complexes; Proliferative potential
• ISSN: 0020-1693
• DOI: 10.1016/j.ica.2024.122457

[Display omitted] •The synthesis of new palladium complexes with terpene ligands is presented.•The study of the toxic effect was carried out on various cell lines of tumor.•The ability of palladacycles to suppress the proliferative potential of cells of tumor origin was revealed. (1R,5S)-(–)-Myrtenal and benzylamine derivatives were synthesized as ligands. The cyclopalladation of the resulting benzyl imines and amines was studied for the first time. High regioselectivity of the cyclometalation of myrtenal benzylimines was shown – under all conditions studied, the vinyl proton is replaced with the formation of Csp2-palladacycles. In the case of amines the result of the palladation reaction depends significantly on the conditions. When palladium acetate is used, the reaction is complicated by the dehydrogenation of amines to the corresponding imines and the cyclopalladation of the latter. Ortho-palladation on the aromatic ring is possible only in the case of amine containing an α-methylbenzylamine moiety. All new compounds were characterized by NMR, IR spectroscopy, and elemental analysis. When studying the biological activity of the synthesized complexes revealed the ability of palladacycles based on myrtenal and benzylamine derivatives to reduce the viability of cells of tumor origin, as well as to inhibit the the proliferative potential of cells, which may be related to the ability to cause apoptosis induction.