Fluorescamine derivative, chiroptical

On the basis of these results, it is apparent that the derivation of the absolute configuration of a COOH- or NH2-terminal amino acid in a dipeptide from its chiroptical properties is hazardous, and a comparison of spectral data with those of proper model peptides is needed. Thus, a more reliable technique is to react the NH2-terminal (or COOH-terminal) amino acid of a small peptide with a proper chromophoric reagent, as discussed above (via Edman degradation or other techniques). Cyclic peptides have to undergo at least partial acid hydrolysis before they can be reacted with methyl isothiocyanate, fluorescamine, etc. 

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