5-Bromo-6-chloro-3-indolylphosphoric acid p-toluidine salt
[CAS# 6769-80-8]

Identification

• Classification: Chemical reagent >> Organic reagent >> Amine salt (ammonium salt)
• Name: 5-Bromo-6-chloro-3-indolylphosphoric acid p-toluidine salt
• Synonyms: Magenta(TM) phosphate
• Molecular Formula: C₈H₆BrClNO₄P^.C₇H₉N
• Molecular Weight: 433.63
• CAS Registry Number: 6769-80-8
• SMILES: CC1=CC=C(C=C1)N.C1=C2C(=CC(=C1Br)Cl)NC=C2OP(=O)(O)O

Properties

• Melting point: 198-200 ºC

Safety Data

• Hazard Symbols: GHS07 Warning
• Hazard Statements: H315-H319-H335
• Precautionary Statements: P261-P305+P351+P338

Discovory and Applicatios

5-Bromo-6-chloro-3-indolylphosphoric acid p-toluidine salt is a chemical compound that belongs to the class of substituted indolyl phosphoric acid derivatives. This compound features a 3-indolylphosphoric acid moiety substituted with bromine at the 5-position and chlorine at the 6-position on the indole ring. The compound is present as a salt formed with p-toluidine, an aromatic amine, which acts as a counterion stabilizing the phosphoric acid group.

The compound is structurally related to chromogenic substrates commonly used in enzymatic assays, particularly those involving phosphatase enzymes. The presence of the indolylphosphoric acid group makes it a potential substrate for alkaline phosphatase and other phosphatases, where enzymatic cleavage releases a chromophore that can be detected spectrophotometrically.

This type of compound was developed to improve the sensitivity and specificity of enzyme activity detection. Substitution with halogens such as bromine and chlorine on the indole ring modulates the chemical and spectral properties, including solubility, stability, and colorimetric response upon enzymatic cleavage. These modifications can enhance the utility of the compound in biochemical assays.

Applications of 5-bromo-6-chloro-3-indolylphosphoric acid p-toluidine salt primarily include its use as a substrate in biochemical and diagnostic assays to detect phosphatase activity. It serves as a chromogenic reagent in color development assays where enzymatic hydrolysis releases an indolyl derivative that undergoes subsequent chemical reactions to form colored products. This color change is measurable and correlates with enzyme concentration or activity.

Such substrates are widely employed in research, clinical diagnostics, and biotechnology for monitoring phosphatase enzymes, which play key roles in cellular signaling, metabolism, and regulation. The ability to detect phosphatase activity sensitively aids in enzyme characterization, screening of inhibitors, and diagnostic tests for diseases involving abnormal enzyme function.

The formation of a salt with p-toluidine enhances the compound’s handling properties, including solubility and stability, facilitating its use in aqueous assay systems. The choice of p-toluidine as the counterion is based on its basicity and compatibility with the indolylphosphoric acid, allowing the compound to maintain its functional activity under assay conditions.

In summary, 5-bromo-6-chloro-3-indolylphosphoric acid p-toluidine salt is a halogenated indolylphosphoric acid derivative used as a chromogenic substrate for phosphatase enzymes. Its structural modifications and salt form improve assay performance, making it a valuable reagent in enzymology and diagnostic applications.

References

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DOI: 10.1177/42.4.8126379

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2023. Effect of Expression of the NDB2 Heterologous Gene of Arabidopsis thaliana on Growth and Respiratory Activity of Nicotiana tabacum. Russian Journal of Plant Physiology, 70(3).
DOI: 10.1134/s1021443723600885