Author/Authors :
Naidu، نويسنده , , B.Narasimhulu and Li، نويسنده , , Wenying and Sorenson، نويسنده , , Margaret E. and Connolly، نويسنده , , Timothy P. and Wichtowski، نويسنده , , John A. and Zhang، نويسنده , , Yunhui and Kim، نويسنده , , Oak K. and Matiskella، نويسنده , , John D. and Lam، نويسنده , , Kin S. and Bronson، نويسنده , , Joanne J. and Ueda، نويسنده , , Yasutsugu، نويسنده ,
Abstract :
Nocathiacins are densely functionalized cyclic thiazolyl peptide natural products with potent in vitro and in vivo antibacterial activity against a variety of gram-positive bacteria, including a number of multiple drug-resistant strains. Attempts to prepare Michael adducts using known conditions resulted in the formation of complex mixture of products. In order to overcome this problem, we developed unique conditions in which Michael addition of amine and thiol nucleophiles to the dehydroalanine moiety of nocathiacins was successfully achieved in frozen water. Under these conditions, the Michael addition was highly chemoselective, very efficient and provided good isolated yields of the desired products.
Keywords :
Michael addition , Frozen water , Dehydroalanine , Nocathiacins
