Improved chromatographic identification of coloured amino acid thiohydantoins

• Published in: Journal of Chromatography A 1977-02, Vol.132 (2), p.303-307
• Main Authors: Chang, J.Y., Creaser, E.H.
• Format: Article
• Language: English
• Subjects: DABITC = 4-N,N-dimethylaminoazobenzene-4′-isothiocyanate; DABTC = 4-N,N-dimethylaminoazobenzene-4′-thiocarbamoyl; DABTH = 4-N,N-dimethylaminoazobenzene-4′-thiohydantoin; DANABITC = 4-N,N-dimethylaminonaphthylazobenzene-4′-isothiocyanate; DANABTC = 4-N,N-dimethylaminonaphthylazobenzene-4′-thiocarbamoyl; DANABTH = 4-N,N-dimethylaminonaphthylazobenzene-4′-thiohydantoin
• ISSN: 0021-9673
• DOI: 10.1016/S0021-9673(00)89304-8

A new N-terminal reagent for peptides and proteins, 4-N,N-dimethylaminonaphthylazobenzene-4′-isothiocyanate, is described which gives purple thiohydantoin derivatives; chromatographic separation of 24 amino acid thiohydantoins is reported. Such standard purple derivatives can be used as markers in the separation of the red 4-N,N-dimethylaminoazobenzene-4′-thiohydantoins. Conversely, standard red thiohydantoins can be used as markers in the separation of unknown purple amino acid thiohydantoins. In two-dimensional thin-layer chromatography, the precision of identifying the unknowns can be greatly improved by running markers with a colour different from the unknowns on the same side of the sheet.