Labelling of amino-acid side-chains with 13C-labelled electrophiles; potential application to the probing of active sites of enzymes

Side-chain groups in functional amino-acids appropriately protected at both terminii have been treated with electrophilic inhibitors (e.g acrylonitrile), 13C n.m.r. spectroscopy allowing unambiguous elecidation of the reacting side-chain functionality; an extension of this technique using 13C-enriched inhibitors to the study of enzyme active-site environment is discussed.