Comparison of four fluorescence Edman reagents with benzofurazan structure for the detection of thiazolinone amino acid derivatives

Fluorogenic and fluorescent labeling reagents with a benzofurazan skeleton

“…At the cyclization and cleavage reaction, the use of boron trifluoride-etherate (BF 3 ) instead of TFA suppresses the racemization of DBD-TZ derivatives (Matsunaga et al, 1996a) and the method for the amino acid sequence and D/L-configuration determination were established using DBD-NCS (Matsunaga et al, 1996b). The reports on the comparison of DBD-NCS with other benzofurazan isothiocyanates reported that DBD-NCS was the most suitable reagent for the detection of TZ derivatives (Matsunaga et al, 1997;Toriba et al, 1999). DBD-NCS was also useful for the Edman sequence with the detection of carbamoyl (CA) derivatives.…”

“…Recently, the effects of the substituent groups of benzofurazan compounds on the fluorescence characteristics have been studied , and the following new fluorogenic reagents have been developed based on the studies: AABD-SH (7-acetylamino-4-mercapto-2,1,3-benzoxadiazole) for carboxylic acids , 1, isocyanate] for alcohols (Uchiyama et al, 1999a) and 1, isothiocyanate] for peptide sequencing analysis (Toriba et al, 2000a).…”

“…The TH derivatives were separated using HPLC and the detection limits were 20 fmol (S/N = 3). Using this method, the sequencing of [D-Ala 2 ]-deltorphin II was succeeded by reverse and chiral stationary phase-HPLC (Toriba et al, 2000a). …”

An automated fluorescence protein sequencer using 7‐methylthio‐4‐(2,1,3‐benzoxadiazolyl) isothiocyanate (MTBD‐NCS) as an Edman reagent

“…For this study, we have synthesized 7-methylthio-4-(2,1,3-benzoxadiazolyl)isothiocyanate (MTBD-NCS; Toriba et al, 2000) (Fig. 1).…”

“…To overcome these disadvantages, we have reported a modified procedure using the following fluorescent benzofurazan Edman reagents: 7-(N,N-dimethylamino)-sulfonyl-4-(2,1,3-benzoxadiazolyl) isothiocyanate (DBD-NCS; Matsunaga et al, 1995) and 7-methylsulfonyl-4-(2,1,3-benzoxadiazolyl) isothiocyanate (MSBD-NCS; Toriba et al, 1999). From these agents, the TZ amino acids generated by cyclization/cleavage reaction can be detected fluorimetrically, since the TZ-amino acids of these reagents were much more stable than those generated from PITC.…”