Synthesis of 1,3-selenazine and 1,3-selenazole and their biological activities

Though sulfur-containing heterocyclic compound syntheses have been extensivly studied, syntheses of selenium analogues have not been appreciably investigated. Recently, however, reports of selenium-containing heterocyclic compound synthesis have gradually increased not only because of their interesting reactivities but also because of their pharmaceutical applications. For example, 1,3-selenazines showed significant anti-bacterial activity against both Gram-negative and Gram-positive bacteria and potential anti-tumor effects against several kinds of human cancer cell lines. Selenazofurin (2-beta-D-ribofuranosylselenazole-4-carboxamide) demonstrated significant anti-tumor properties in animals and broad spectrum antiviral activity in cell culture experiments. Selenoureas and selenoamides have been used as the precursors for the most of the syntheses of 1,3-selenazines and 1,3-selenazoles. This review article summarizes the recent progress in the development of the synthesis methods of 1,3-selenazine and 1,3-selenazole and their biological significances.