Organochalcogen Compounds: Synthesis and Prospective as Therapeutic Agents

Organochalcogens compounds are organic derivatives that contain at least one of the chemical elements in group 16 of the periodic table, also known as the oxygen family. In this class of compounds, the oxygen, sulfur and selenium containing derivatives are the most popular. In this mini-thematic issue, the attention was especially focused on selenium and sulphur containing organic compounds with peculiar biological properties. Even though organoselenium derivatives have a more recent history than organosulfurs, they immediately proved to be of great importance both from the point of view of chemistry and biochemistry. In the class of organosulfur compounds, it is possible to find molecules with important biological activities. Just to name a few: the two natural occurring amino acids cysteine and methionine, antibiotics such as penicillins, cephalosporins and sulphamides (sulpha drugs) etc. Despite the preparation of the first organoselenium compounds is dated back to 1836, the design and synthesis of a large variety of molecules was explored in depth starting from ‘70s, attracting even more general interest during the years. Although organoselenium species has been proven to be valuable reagents in chemistry, (regio- stereoselective or stereospecific reactions in synthetic transformations such as selenenylation, selenocyclization, selenoxide elimination and 2,3-sigmatropic rearrangement processes as well as asymmetric catalysis), in these last 20 years, the attention toward organoselenium derivatives is increased, due to their interesting biological activities. Researches have also demonstrated the essential role of Selenium in the human health as an important element involved in many biological processes. Thus, the study of organochalcogen compounds is of a crucial importance for the development of new potential therapeutic agents for the treatment of cancer, pain, inflammation, neurodegenerative, and infection diseases. Several examples of organoselenium compounds, such as 1,2,3-selenadiazoles, diselenides, selenocyanates, ebselen and its analogues, selenoquinolines, selenopyridazine and selenopyridine and selenonucleoside analogues, were reported to show interesting biological activity.