CNP-α-L-Fuc (2-Chloro-4-nitrophenyl-α-L-fucopyranoside, CAS 157843-41-9) is a chromogenic substrate specifically designed for quantitative spectrophotometric assay of α-L-fucosidase (AFU, EC 3.2.1.51) activity, where enzymatic hydrolysis releases 2-chloro-4-nitrophenolate (2-Cl-4-NP) chromophore exhibiting intense yellow absorbance at 405 nm (ε=12,400 M⁻¹cm⁻¹) for precise kinetic measurement in clinical diagnostics and research applications. With molecular formula C12H14ClNO7 (MW 319.70 g/mol), this white crystalline solid features α-L-fucopyranose (6-deoxy-L-galactose) linked via α1-O-glycosidic bond to the electron-deficient 2-chloro-4-nitrophenyl aglycone, where ortho-chloro and para-nitro groups enhance leaving group acidity (pKa ~7.0) and hydrolysis rates (kcat/Km ~10³-10⁴ M⁻¹s⁻¹ for human lysosomal AFU and bacterial Fusobacterium α-fucosidases), ensuring >500-fold selectivity over β-fucosidases. Widely utilized in fucosidosis diagnostics (FUCA1 deficiency), cancer biomarker screening (elevated plasma AFU in malignancies), and glycobiology for profiling GH29 family fucosidases in microbiome HMO degradation, it supports one-step 96-well assays (0.5-2 mM substrate, pH 4.5-5.0, 37°C) with linear detection from 0.01-10 U/L, outperforming p-nitrophenyl-α-L-Fuc by faster turnover and reduced endogenous interference. The released chromophore’s stability across pH 6-10 enables ratiometric endpoint reads, positioning CNP-α-L-Fuc as gold standard for therapeutic monitoring, enzyme replacement therapy efficacy, and HTS of fucosidase inhibitors targeting inflammation, infection, and Lewis antigen metabolism disorders.
Appearance
- White crystalline powder.
- Hydrolysis produces yellow solution (A₄₀₅).
Source
- Koenigs-Knorr synthesis: α-L-fucopyranosyl halide + 2-chloro-4-nitrophenol.
- Commercial analytical grade (Biosynth, Chemsynlab >98%).
Molecular Weight and Structure
- Formula: C₁₂H₁₄ClNO₇; MW: 319.70 g/mol.
- (2S,3S,4R,5S,6S)-2-(2-chloro-4-nitrophenoxy)-6-methyloxane-3,4,5-triol.
Sugar Specificity
- Selective α-L-fucopyranoside for α-L-fucosidases (GH29).
- Negligible β-fucosidase activity.
Biological Activity
- Chromogenic AFU substrate; 1 U = 1 μmol CNP/min at 37°C.
- Kinetic assay at 405 nm.
Purity and Microbial Contamination
- ≥98% (HPLC, IR, NMR); heavy metals <20 ppm.
- Synthetic; non-sterile.
Identity and Quality Control
- [α]D -172.5°; mp 155-158°C; TLC single spot.
- MS/NMR verified; residue on ignition <0.5%.
Shelf Life and Storage
- Stable >2 years -20°C desiccated; DMF soluble.
- Avoid moisture/light.
Applications
- Fucosidosis diagnostics; cancer AFU biomarker.
- Glycobiology enzyme assays, HMO research.
Key Characteristics
- High specificity; sensitive 405 nm detection.
- Superior to pNP-α-L-Fuc kinetics.
Citation Links
Reviews
There are no reviews yet.