Fluorescent oxidation products derived from DBD-thiocarbamoyl amino acid in the modified Edman sequencing analysis

The fluorescent product obtained by the oxidation of 7-N,N-dimethylaminosul fonyl-4-(2, 1,3-benzoxadiazolyl) (DBD)-thiocarbamoyl (TC)-proline with NaNO 2/H+ in the modified Edman sequencing procedure was identified as the corre sponding thiazolyl compound, N-[(8-dimethylaminosulfonyl)thiazolo [5,4,e]be nzo[2,1,3]oxadiazol-5-yl]-L-proline, formed by the attack of the sulfur ato m of the thiocarbamoyl group on the benzofurazan skeleton. The reaction mec hanism for the formation of the fluorescent compound from DBD-TC primary an d secondary amines is also discussed. Copyright (C) 2000 John Wiley & Sons, Ltd.