Protein thioacylation. 1. Reagents design and synthesis

Thioacylation is a new way for protein chemical modification. Carboxylic di thioesters and -acids react selectively and rapidly at room temperature wit h aliphatic amines such as lysine epsilon -amino groups leading to thioamid e formation, without any other reagent or catalyst. Various thioacylating r eagents were synthesized: monofunctional dithioesters bearing on the acylat ing end various chemical groups such as: aliphatic chains, phenyl group, mo no- and dicarboxylic acids, dialkylphosphonic ester, phosphonic acid, thiol , phenol, or quaternary ammonium group. Bifunctional dithioesters containin g either a polymethylene chain or an ethylene oxide oligomer as spacer grou p as well as some mono- and bis(dithio acids) are described. Applications o f thioacylation may be involved either in enzyme chemical modifications or in the obtention of new materials from proteins. Bifunctional reagents migh t be used as cross-linking or coupling reagents.