對(duì)硝基苯基-b-D-吡喃木糖苷，4-Nitrophenyl b-D-xylopyranoside

4-nitrophenyl beta-D-xyloside is a xyloside that is beta-D-xylopyranose in which the anomeric hydroxy hydrogen is replaced by a 4-nitrophenyl group. It has a role as a chromogenic compound. It is a xyloside and a C-nitro compound. It derives from a 4-nitrophenol.

4-Nitrophenyl beta-D-xyloside (NPX) is a derivative of xylose, which is a five-carbon sugar. This compound has been studied extensively in the field of enzymology due to its ability to mimic the natural substrate for the enzyme β-xylosidase. In this review, we will discuss the definition and background of NPX, its physical and chemical properties, synthesis and characterization, analytical methods, biological properties, toxicity and safety in scientific experiments, applications in scientific experiments, current state of research, potential implications in various fields of research and industry, limitations, and future directions.

Definition and Background:

NPX is a chromogenic substrate used to assay β-xylosidase activity. It is a water-soluble compound that is colorless but turns yellow upon the action of β-xylosidase. β-xylosidase is a glycoside hydrolase enzyme that cleaves xylose residues from the non-reducing end of xylooligosaccharide chains. NPX is one of the most commonly used β-xylosidase substrates due to its excellent sensitivity and stability.

Physical and Chemical Properties:

NPX is a crystalline solid that is soluble in water, methanol, and ethanol. It has a melting point of 185-186°C and a molecular weight of 325.26 g/mol. NPX has the chemical formula C14H15NO7 and the CAS Number 76592-88-0.

Synthesis and Characterization:

NPX can be synthesized through a multi-step process, starting with xylose and nitrophenol. The first step is the protection of the xylose hydroxyl groups using tert-butyldimethylsilyl (TBS) chloride to produce TBS-xylose. This is followed by the selective deprotection of the C-2 hydroxyl group using acetic anhydride to yield 2,3,5-tri-O-acetyl-1-O-TBS-xylose. The final step is the reaction of 2,3,5-tri-O-acetyl-1-O-TBS-xylose with nitrophenol in the presence of trifluoroacetic acid to produce NPX.

NPX can be characterized by various spectroscopic techniques such as ^1H and ^13C NMR, IR, and UV-Vis spectroscopy. The melting point and elemental analysis can also be used to confirm its identity.

Analytical Methods:

The most common method used to analyze NPX hydrolysis is UV-Vis spectroscopy, which measures the absorbance at 400 nm of the yellow p-nitrophenol product formed by the action of β-xylosidase on NPX. High-performance liquid chromatography (HPLC) can also be used to monitor the hydrolysis of NPX.

Biological Properties:

NPX has been widely used in enzymology studies due to its ability to mimic the natural substrate for β-xylosidase. It has been used to study the catalytic mechanism of β-xylosidase and to screen for new β-xylosidase inhibitors. NPX has also been used to study the activity of other enzymes, such as α-L-fucosidase and α-L-arabinofuranosidase.

Toxicity and Safety in Scientific Experiments:

There is limited information available on the toxicity of NPX. However, it is recommended to handle NPX with care and to follow standard safety guidelines for chemical handling.

Applications in Scientific Experiments:

NPX is mainly used in the enzymology field as a chromogenic substrate for β-xylosidase. It has also been used in the study of other enzymes such as α-L-fucosidase and α-L-arabinofuranosidase.

Current State of Research:

The use of NPX has expanded beyond the enzymology field. It has been used as a substrate for the detection of pathogenic bacteria and viruses. NPX has also been used to study the properties of cellulose and the enzymes involved in cellulose degradation. Furthermore, it has potential applications in the bioconversion of lignocellulosic biomass to biofuels.

Potential Implications in Various Fields of Research and Industry:

The potential applications of NPX extend beyond the enzymology and biofuels fields. NPX can be used as a substrate for the detection of bacteria and viruses in water and food samples. It can also be used as a carbohydrate mimic to study the interactions between carbohydrates and proteins. Furthermore, the application of NPX in the study of cellulose degradation enzymes could lead to the development of new methods for lignocellulose bioconversion to renewable energy.

Limitations and Future Directions:

One limitation of NPX is its specificity towards β-xylosidase. It cannot be used to study the activity of other enzymes that cleave different glycosidic bonds. Moreover, the current synthesis of NPX is lengthy and involves the use of reactive and toxic reagents.

Future directions for NPX research should focus on the development of efficient and sustainable synthesis methods. Additionally, the use of NPX in the detection of bacteria and viruses could be expanded to develop low-cost diagnostic tools in resource-limited settings. Finally, further studies should be conducted to explore the potential of NPX in the development of novel biofuels and bioproducts.

Conclusion:

In conclusion, 4-Nitrophenyl beta-D-xyloside is a versatile compound with a wide range of applications in the enzymology, biofuels, and biorefinery fields. It is a highly sensitive and stable substrate for β-xylosidase that has potential applications in the development of diagnostic tools and the bioconversion of lignocellulosic biomass to renewable energy. However, there are limitations to its specificity and current synthesis methods. Further research is needed to improve the synthesis of NPX, explore its potential in various fields and to develop sustainable applications.

COA:

Product name: 4-Nitrophenyl beta-D-xylopyranoside; PNPX   

CAS: 2001-96-9       M.F.: C₁₁H₁₃NO₇           M.W._: 271.22

4-Nitrophenyl beta-D-xylopyranoside is one of substrates for detn. of beta-xylosidase activity.