Second and third-row transition metal compounds containing benzimidazole ligands: An overview of their anticancer and antitumour activity

Abstract

The application of metal compounds in the medical field dates back to the XVI century with some isolated reports about the therapeutic importance of metals and their compounds in the treatment of various diseases, including cancer. Nowadays, the number of commonly prescribed metal-containing compounds is very broad and includes antimony (antiprotozoal), bismuth (antiulcer), iron (antimalarial), gold (antiarthritic), silver (antimicrobial), platinum (anticancer), and vanadium (antidiabetic), among others. Most biological molecules, such as DNA or proteins, are rich in electron density, while metal ions lack electrons. For that reason, we can observe a marked trend in which metal ions interact with various molecules of biological interest. Furthermore, metal ions also have a great affinity for various tiny molecules, such as molecular oxygen, which are essential to life. During the last sixty years, several classes of new metal derivatives, mainly organometallic and coordination compounds have been intensively investigated as possible anticancer and/or antitumour agents based on a great variety of metals, mainly from the d-block.