Hydrazine-sensitive thiol protecting group for peptide and protein chemistry.

In the search for a new Cys side-chain protecting group that is compatible to the solid-phase peptide synthesis yet can be removed under mild conditions, the Hqm and Hgm groups that are readily deprotected by using aqueous hydrazine have been developed. The utility of these groups for peptide and protein chemistry is tested by the total synthesis of a peptide antibiotic trifolitoxin and the human neutrophil defensin hNP2.