Selenium represents an essential element for organisms as various diseases can result from selenium deficiency. As a consequence, selenium-containing heterocycles are of considerable biochemical and pharmacological relevance. Selenium-containing heterocycles are often less stable than the corresponding sulfur analogues. Therefore, the investigation of new methods for the synthesis of small selenium-containing building blocks is of considerable interest. This review describes the use of biologically significant selenium-containing heterocycles from the viewpoint of chemical structures. (C) 2011 Elsevier B.V. All rights reserved.