Developments in the chemistry of selenaheterocyclic compounds of practical importance in synthesis and medicinal biology

The heterocyclic compounds with selenium atom in the ring such as selenirenes, selenophenes, selenadiazoles, selenatriazoles, benzisoselanazolones and some others are presented as the reagents and intermediates employed in synthesis of alkenes, alkynes and nonselenium heterocycles or as the catalysts for hydroperoxide oxidation of various groups of organic compounds. Selenaheterocyclic compounds, particularly the benzisoselenazol-3(2H)-ones and other cyclic selenenamides, seleninate esters, spirodioxyselenuranes, selenium-containing nucleoside analogues, selenazines and selenazoles are shown as antioxidants, anti-inflammatory agents, virucides, bacteriocides, fungicides, cytokine inducers and immunomodulators. The chemical and biological activity of the presented compounds and the mechanisms of their action are discussed.