Propargylic ureas as powerful and versatile building blocks in the synthesis of various key medicinal heterocyclic compounds

Document Type : Review Article


1 Department of Chemistry, Center for Photochemical Sciences, Bowling Green State University, Bowling Green, Ohio 43403, USA

2 Department of Chemistry and Earth Sciences, College of Arts and Science, Qatar University, P.O. Box 2713, Doha, Q

3 Department of Chemistry, Tabriz Branch, Islamic Azad University, Tabriz, Ira

4 Department of Chemistry, Payame Noor University, P. O. Box: 19395-4697, Tehran, Iran


This review article is an attempt to highlight the most important contributions toward the synthesis of various nitrogen-containing heterocyclic compounds from corresponding propargylic ureas through regio- and chemoselective 5-exo-dig and 6-endo-dig modes of N- and O-cyclization reactions. The review is divided into three major sections. In the first section we only focus on 5-exo-dig N-cyclization fashion. In the second section 5-exo-dig O-cyclization is described. The third section is devoted to 6-endo-dig N- and O-cyclizations

Graphical Abstract

Propargylic ureas as powerful and versatile building blocks in the synthesis of various key medicinal heterocyclic compounds


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