Sanger’s reagent

Fluoro 2 4 dimtrobenzene IS commonly referred to as Sanger s reagent... 

Carboxypeptidase catalyzed hydrolysis can be used to identify the C terminal ammo acid The N terminus is determined by chemical means One reagent used for this purpose is Sanger s reagent 1 fluoro 2 4 dimtrobenzene (see Figure 27 9)... 

Sanger s reagent (Section 27 11) The compound 1 fluoro 2 4 dimtrobenzene used in N terminal ammo acid identifica tion... 

Dinitrofluorobenzene (Sanger s reagent) [70-34-8] M 186.1, m 25-27 , b 133 /2mm, 140-141 /5mm, d 1.483. Crystd from ether or EtOH. Vacuum distd through a Todd Column (see p. 174). If it is to be purified by distn in vacuo, the distn unit must be allowed to cool before air is allowed into the apparatus otherwise the residue carbonises spontaneously and an EXPLOSION may occur. The material is a skin irritant and may cause serious dermatitis. 

Acid fluondes such as oxalyl fluoride, tnchloroacetyl fluonde, propionyl fluonde, as well as Sanger s reagent, 2,4-dinitrofluorobenzene, easily cleave N,N-acetals (aminals) to give high yields of fluoromethyldialkylamines [82] (equation 20) (Table 5)... 

Nucleophilic aromatic substitution is much less common than electrophilic substitution but nevertheless does have certain uses. One such use is the reaction of proteins with 2,4-dinitrofluorobenzene, known as Sanger s reagent, to attach a "label" to the terminal NH2 group of the amino acid at one end of the protein chain. 

The amino group of the N-terminal amino acid residue of a peptide will react with the FDNB reagent to form the characteristic yellow DNP derivative, which may be released from the peptide by either acid or enzymic hydrolysis of the peptide bond and subsequently identified. This is of historic interest because Dr F. Sanger first used this reaction in his work on the determination of the primary structure of the polypeptide hormone insulin and the reagent is often referred to as Sanger s reagent. 

A-aryl amino acids (such as DNP, DNPyr, DBD, and NBD labeled amino acids) Some of these derivatives are the preferred choice for many analytical purposes because they can be conveniently introduced by straightforward and smooth derivatization procedures. This holds in particular for the Sanger s reagent... 

A number of nonnatural amino acids were resolved into individual enantiomers on 0-9-(2,6-diisopropylphenylcarbamoyl)quinine-based CSPby Peter and coworkers [48,90,113,114] after derivatization with Sanger s reagent, chloroformates (DNZ-Cl, FMOC-Cl, Z-Cl), Boc-anhydride, or acyl chlorides (DNB-Cl, Ac-Cl, Bz-Cl). For example, the four stereoisomers of P-methylphenylalanine, P-methyltyrosine, P-methyltryptophan, and P-methyl-l,2,3,4-tetrahydroisoquinoline-3-carboxylic acid could be conveniently resolved as various A-derivatives [113]. The applicability spectrum of cinchonan carbamate CSPs comprises also P-amino carboxylic acid derivatives, which were, for example, investigated by Peter et al. [114]. A common trend in terms of elution order of DNP-derivatized P-amino acids was obeyed in the latter study On the utilized quinine carbamate-based CSP, the elution order was S before R for 2-aminobutyric acid, while it was R before S for the 3-amino acids having branched R substituents such as wo-butyl, iec-butyl, tert-butyl, cyclohexyl, or phenyl residues. 

In yet another study, the simultaneous separation of the four stereoisomers of a-amino-P-hydroxy propane phosphonic acids as well as the corresponding P-amino-a-hydroxy propane phosphonic acids could be successfully accomplished after labeling with Sanger s reagent [119]. 

Number of Polypeptide Chains in a Multisubunit Protein A sample (660 mg) of an oligomeric protein of Mr 132,000 was treated with an excess of l-fluoro-2,4-dinitrobenzene (Sanger s reagent) under slightly alkaline conditions until the chemical reaction was complete. The peptide bonds of the protein were then completely hydrolyzed by heating it with concentrated HC1. The hydrolysate was found to contain 5.5 mg of the following compound ... 

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