APPLICATION OF SPONTANEOUS SCHIFF-BASE COPPER-CHELATES FORMATION PROCESS TO THE DESIGN OF A TRYPSIN-INHIBITOR

Salicylaldehyde derivatives carrying an amidinium group react spontane ously with alpha-amino acids in copper-containing aqueous media to aff ord very stable Schiff base copper chelates. A variety of Schiff base chelates were prepared from various alpha-amino acids. Each alpha-amin o acid provides enantiomeric isomers due to the asymmetric alpha-carbo n, except for glycine. Inhibitory activity of these amidinium chelates toward trypsin was generally very strong. Thus these compounds repres ent a novel series of potent trypsin inhibitors. The structure-activit y relationship of the inhibitors is discussed based on their inhibitio n constants, though the variations are not large.