Palladium pincer complex of normal and abnormal carbenes , synthesis and their application as anti-cancer agent Number (to be inserted by us) Jing-Yi Lee, Jhen-Yi Lee, Wang NM* and Hon Man Lee* Department of Chemistry, National Changhua University of Education, Changhua 50058, Taiwan, Republic of China. E-mail: leehm@cc.ncue.edu.tw; Fax: +886 4 7211190; Tel: +886 4 7232105, ext. 3523 Institute of Biotechnology, National Changhua University of Education, Changhua50058, Taiwan, Republic of China. E-mail: nancy@cc.ncue.edu.tw; Fax: +886 4 7211156; Tel: +886 4 7232105, ext. 3459 Abstract: The synthesis of unique N-heterocyclic carbene (NHC) ligand precursors is presented. The structures of the ligand precursors include N-heterocyclic carbene, amine, and pyridine as functional groups. They can be used to form tridentate palladium NHC complexes. By rational control of the metal source and reaction conditions, an isomeric pair with normal and abnormal carbene of palladium complexes can be obtained. Abnormal carbene of palladium complex has not been applied as anticancer agents. We successfully discover that the abnormal carbene palladium complexes have good effect in anticancer activities. References 1 I. J. B. Lin and C. S. Wasam, Coord. Chem. Rev., 2007, 251, 642. J. H. Kim, J. W. Kim, M. Shokouhimehr and Y. S. Lee, J. Org. Chem., 2005, 70, 6714. 3 L. Mercs and M. Albrecht, Chem. Soc. Rev., 2010, 39, 1903. 4 W. Li and R. Gust, Chem. Soc. Rev., 2013, 42, 755 5 R. D. Graham and D. R. Williams, J. Inorg. Nucl. Chem., 1979, 41, 1245. 6 A. R. Kapdi, I. J. S. Fairlamb, Chem. Soc. Rev., 2014 2