Efficient guanylation of aromatic and heterocyclic amines catalyzed by cyclopentadienyl-free rare earth metal amides

Synthetic and natural guanidine derivatives as antitumor and antimicrobial agents: A review

Guanidines are fascinating small nitrogen-rich organic compounds, which have been frequently associated with a wide range of biological activities. This is mainly due to their interesting chemical features. For these reasons, for the past decades, researchers have been synthesizing and evaluating guanidine derivatives. In fact, there are currently on the market several guanidine-bearing drugs. Given the broad panoply of pharmacological activities displayed by guanidine compounds, in this review, we chose to focus on antitumor, antibacterial, antiviral, antifungal, and antiprotozoal activities presented by several natural and synthetic guanidine derivatives, which are undergoing preclinical and clinical studies from January 2010 to January 2023. Moreover, we also present guanidine-containing drugs currently in the market for the treatment of cancer and several infectious diseases. In the preclinical and clinical setting, most of the synthesized and natural guanidine derivatives are being evaluated as antitumor and antibacterial agents. Even though DNA is the most known target of this type of compounds, their cytotoxicity also involves several other different mechanisms, such as interference with bacterial cell membranes, reactive oxygen species (ROS) formation, mitochondrial-mediated apoptosis, mediated-Rac1 inhibition, among others. As for the compounds already used as pharmacological drugs, their main application is in the treatment of different types of cancer, such as breast, lung, prostate, and leukemia. Guanidine-containing drugs are also being used for the treatment of bacterial, antiprotozoal, antiviral infections and, recently, have been proposed for the treatment of COVID-19. To conclude, the guanidine group is a privileged scaffold in drug design. Its remarkable cytotoxic activities, especially in the field of oncology, still make it suitable for a deeper investigation to afford more efficient and target-specific drugs.

An amidato divalent ytterbium cluster: synthesis and molecular structure, its reactivity to carbodiimides and application in the guanylation reaction

An amidato Yb(ii) cluster 1 was synthesized and well characterized. Cluster 1 reacted with DIC to provide three new Yb(iii) complexes, and it was found to be an excellent pre-catalyst for the guanylation reaction.

Synthesis, characterization and catalytic activity of rare-earth metal amides incorporating cyclohexyl bridged bis(β-diketiminato) ligands

The bridged bis(β-diketiminato) ligands supported rare-earth amides exhibited high catalytic activity towards the hydrophosphination of β-nitroalkene and α,β-unsaturated carbonyl derivatives with an excellent regioselectivity.

Synthesis and characterization of bridged bis(amidato) rare earth metal amides and their applications in C–N bond formation reactions

Eight bis(amidato) rare-earth metal amides were successfully synthesized and well characterized, which exhibited high catalytic activities in both the direct amidation of aldehydes and the addition of amines with carbodiimine.

Recent development of synthetic preparation methods for guanidines via transition metal catalysis

This article provides an overview of guanidine synthesis via transition-metal-catalyzed reactions including cycloaddition, guanylation and tandem guanylation/cyclization.

Synthesis and characterization of bis(amidate) rare-earth metal amides and their application in catalytic addition of amines to carbodiimides

Five bis(amidate) rare-earth metal amides were successfully employed in guanidination, and the Nd-based catalyst showed the highest reactivity.

Catalytic addition of amines to carbodiimides by bis(β-diketiminate)lanthanide(ii) complexes and mechanistic studies

Bis(β-diketiminate)lanthanide(ii) complexes L₂Ln(THF)_n were found to be excellent pre-catalysts for catalytic addition of amines to carbodiimides and a possible catalytic mechanism was proposed on the basis of the isolation of monoguanidinate Eu(ii) and bis(guanidinate) Yb(iii) species.

Guanidines: from classical approaches to efficient catalytic syntheses

This review focuses on the metal-mediated catalytic addition of amines to carbodiimides as an atom-economical alternative to the classical synthesis of guanidines.

Isolation and X-ray characterization of palladium-N complexes in the guanylation of aromatic amines. Mechanistic implications

In the context of palladium-catalyzed guanylation of anilines herein, we have been able to characterize and isolate bis(anilino) and bis(guanidino)Pd(II) complexes using reaction conditions under which stoichiometric amounts of palladium salts are used. Characterization of these palladium complexes strongly supports a mechanistic proposal for the catalytic guanylation of anilines using PdCl₂(NCCH₃)₂ as catalyst that involves the intermediacy of these Pd(II) complexes.