Download PDF
Synfacts 2005(0): 0021-0021  
DOI: 10.1055/s-2005-865375
Synthesis of Heterocycles
© Georg Thieme Verlag Stuttgart · New York

Radical-Mediated Synthesis of Sesquiterpene Lactones

Contributor(s): Victor Snieckus, Zhongdong Zhao
E. Jezek, A. Schall, P. Kreitmeier, O. Resier*
University of Regensburg, Germany
Radical Cyclizations as Key Step for the Stereoselective Synthesis of Bi- and Tricyclic Stereoselective Sesquiterpene Lactones
Synlett  2005,  915-918  
Thieme Connect
Further Information

Publication History

Publication Date:
20 July 2005 (online)

 PDF Download Permissions and Reprints

Key words

radical cyclization - natural products - lactones

Significance

Starting from inexpensive methyl 2-furoate, via the intermediate cyclopentenylbutenolide (4 steps, 26% overall yield), bi- and tricyclic g-butyrolactone cores can be formed stereoselectively and in good yields via Y-substituent - directed radical cyclization. Using R = Br, CN, CO2Et, COMe substitution, reactions proceed in acceptable yields.

Comment

trans-Fused seven- or six-membered rings are widespread frameworks in a variety of natural products such as guaianolides. This ste­reoselective strategy may provide new useful synthetic approaches to such derivatives and other natural products containing similar ring systems which to date have been rather limited.

   Permissions and Reprints