Boron Salicylate Ester Compounds as Boron Therapeutics. Their Synthesis, Structural Characterizations and Anticancer...

The element boron forms a wide range of borate minerals with different properties. Borate minerals make it possible to design boron-containing molecules with new biological properties in terms of their chemical structure and properties. It is known that boron compounds have antioxidant, anti-inflammatory, anti-tumor and anti-cancer properties. This makes boron compounds important for the future development of boron chemotherapeutics, boron supplements and new drugs. Reliable scientific studies on boron compounds will facilitate the clear presentation of their functions in its biological applications and metabolism. In this study, boron monoester and boron diester structures were synthesized with salicylic acid ligand. To stabilize boron ester structures, Na⁺, K⁺, Mg²⁺, Ca²⁺ cations were used as counter-ions. Structural properties of the synthesized substances, molecules obtained by crystallization/precipitation from aqueous solutions in solid state, elemental analysis, melting point determination, infrared spectroscopy analysis (FT-IR), thermal analysis (TGA/DTA), mass analysis (GC-MS) and single crystal analysis. Structural properties were tried to be explained by structure analysis (SC-XRD) methods. Additionally, the anticancer potential of boron salicylate esters against the MDA-MB-231 human breast adenocarcinoma cell line was examined. The K-B salicylate diester molecule was found to have the most potential potency with the lowest IC₅₀ value against the MDA-MB-231 cell line. The anticancer potential of boron salicylate esters can be further investigated with other cancer models with the combination of anticancer drugs. It is also thought that the mechanism of action of these molecules may help reveal their further applications.