I wish to acknowledge that our Synlett publication was composed of experimental data that are a duplication of those contained in a paper by the same authors in Tetrahedron 2011, 67, 5339. In addition, I note the unfortunate omission of respective cross references to this publication. As a result, I retract this Synlett paper. I apologize for these serious errors in judgment. �
Sincerely,�
Fung Fuh Wong (Graduate Institute of Pharmaceutical Chemistry, China Medical University, No. Hsueh 91, Shih Rd., Taichung, Taiwan 40402, R. O. C.)�