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Langmuir : the ACS Journal of Surfaces... Jun 2013The emerging fields of nanomotors and optomechanics are based on the harnessing of light to generate force. However, our ability to detect small surface stresses is...
The emerging fields of nanomotors and optomechanics are based on the harnessing of light to generate force. However, our ability to detect small surface stresses is limited by temperature drift, environmental noise, and low-frequency flicker electronic noise. To address these limitations, we functionalized microfabricated silicon cantilevers with an azo dye, silane-based self-assembled monolayer and modulated the surface stress by exciting the optical switch with a 405-nm laser. Atomic force microscopy, contact angle analysis, ellipsometry, and X-ray photoelectron spectroscopy verified successful assembly of molecules on the cantilever. Ultraviolet and visible spectra demonstrate optical switching of the synthesized molecule in solution. By turning the laser on and off at a specific rate (e.g., 1 Hz), the cantilever deflection can be measured via Fourier techniques, thus separating the signal of interest from the noise. This technique empowers the design of highly sensitive surface stress measurements.
Topics: Azo Compounds; Coloring Agents; Molecular Structure; Nanotechnology; Silicon; Surface Properties
PubMed: 23663108
DOI: 10.1021/la3034676 -
Chemical Communications (Cambridge,... May 2021A novel universal N-transfer reagent for direct and effective transformation of α-amino ketones, acetamides, and esters to the corresponding α-diazo products under...
A novel universal N-transfer reagent for direct and effective transformation of α-amino ketones, acetamides, and esters to the corresponding α-diazo products under mild basic conditions has been developed. This one-step synthetic approach not only allows for generation of α-substituted-α-diazo carbonyl compounds from α-amino acid derivatives but also permits preparation of α-diazo dipeptides from N-terminal dipeptides (32 examples, up to 91%).
Topics: Amino Acids; Azo Compounds; Diazonium Compounds; Dipeptides; Indicators and Reagents; Molecular Structure; Salts
PubMed: 33870368
DOI: 10.1039/d1cc01285a -
Current Topics in Medicinal Chemistry 2014This review highlights the biological importance of many polysubstituted nitro-prolines and -pyrrolidines. Their preparation using asymmetric 1,3-dipolar cycloadditions... (Review)
Review
This review highlights the biological importance of many polysubstituted nitro-prolines and -pyrrolidines. Their preparation using asymmetric 1,3-dipolar cycloadditions of azomethine ylides with nitroalkenes using diastereoselective and enantioselective strategies is described remarking the scope and main features of each one.
Topics: Alkenes; Azo Compounds; Cyclization; Models, Molecular; Molecular Conformation; Nitro Compounds; Thiosemicarbazones
PubMed: 24758430
DOI: 10.2174/1568026614666140423112145 -
Spectrochimica Acta. Part A, Molecular... Dec 2010A series of azo disperse dyes were synthesized by coupling reaction of N,N-diethylaniline, 2-anilinoethanol and N-phenyl-2,2'-iminodiethanol with diazotized...
A series of azo disperse dyes were synthesized by coupling reaction of N,N-diethylaniline, 2-anilinoethanol and N-phenyl-2,2'-iminodiethanol with diazotized aminothiazolyl derivatives as diazo components. These dyes have been prepared in good yields, and were characterized by UV-Vis, FT-IR and 1H NMR spectroscopic techniques. The effects of solvent polarity and various pH on dyes in the visible absorption spectra were evaluated. All dyes exhibit an excellent correlation coefficient (r>0.92) for the linear solvation energy relationship with π* values calculated by Kamlet et al. The influence of the pH on the dyes with electron-donating group implied that these dyes exist in acid-base equilibrium in acidic environment. The effect of substituents of both coupler and diazo component on the color of dyes was investigated as well.
Topics: Azo Compounds; Coloring Agents; Heterocyclic Compounds; Models, Biological; Solvents; Structure-Activity Relationship; Thiazoles
PubMed: 20869296
DOI: 10.1016/j.saa.2010.08.079 -
Ecotoxicology and Environmental Safety Sep 2018Synthetic azo dyes have increasingly become a matter of great concern as a result of the genotoxic and mutagenic potential of the products derived from azo dye...
Influence of auxochrome group in disperse dyes bearing azo groups as chromophore center in the biotransformation and molecular docking prediction by reductase enzyme: Implications and assessment for environmental toxicity of xenobiotics.
Synthetic azo dyes have increasingly become a matter of great concern as a result of the genotoxic and mutagenic potential of the products derived from azo dye biotransformation. This work evaluates the manner in which reducing enzymes produced by Escherichia coli (E. coli) act on three disperse dyes bearing azo groups, namely Disperse Red 73 (DR 73), Disperse Red 78 (DR 78), and Disperse Red 167 (DR 167). UV-Vis spectrophotometry, high-performance liquid chromatography with diode array detector (HPLC-DAD), and liquid chromatography mass spectrometry (LC-MS/MS) were applied towards the identification of the main products. Seven days of incubation of the azo dyes with the tested enzymes yielded a completely bleached solution. 3-4-Aminophenyl-ethyl-amino-propanitrile was detected following the biotransformation of both DR 73 and DR 78. 4-Nitroaniline and 2-chloro-4-nitroaniline were detected upon the biotransformation of DR 73 and DR 78, respectively. The main products derived from the biotransformation of DR 167 were dimethyl 3,3'-3-acetamido-4-aminophenyl-azanedyl-dipropanoate and 2-chloro-4-nitroaniline. The results imply that DR 73 lost the CN substituent during the biotransformation. Furthermore, theoretical calculations were also carried out aiming at evaluating the interaction and reactivity of these compounds with DNA. Taken together, the results indicate that DR 73, DR 78, and DR 167 pose health risks and serious threats to both human beings and the environment at large as their biotransformation produces harmful compounds such as amines, which have been widely condemned by the International Agency for Research on Cancer.
Topics: Azo Compounds; Biotransformation; Chromatography, High Pressure Liquid; Coloring Agents; Escherichia coli; Humans; Molecular Docking Simulation; Tandem Mass Spectrometry; Xenobiotics
PubMed: 29793200
DOI: 10.1016/j.ecoenv.2018.04.066 -
Medicinal Chemistry (Shariqah (United... 2023Textile materials are susceptible to microbial attack as they provide suitable conditions for their growth. The microbes grow with normal body secretions on garments....
BACKGROUND
Textile materials are susceptible to microbial attack as they provide suitable conditions for their growth. The microbes grow with normal body secretions on garments. These microbes are responsible for the weakening, brittleness, and discoloration of the substrate. Furthermore, they cause many health issues to the wearer, including dermal infection, bad odour etc. They threaten the human health as well as create tenderness in fabric.
OBJECTIVES
Usually, antimicrobial textiles are prepared by applying antimicrobial finishes after dyeing, which is an expensive approach. Concerning these adversities, in the present study, a series of antimicrobial acid-azo dyes have been synthesized by incorporating antimicrobial sulphonamide moiety into the dye molecules during its synthesis.
METHODS
A commercially available sulphonamide-based compound, sulfadimidine Na-salt was used as a diazonium component and coupled with different aromatic amines to get desired dye molecules. Since dyeing and finishing are two separate energy-intensive processes, in the current research work, an approach to combine both processes in one step has been adopted that would be economical, timesaving, and environment friendly. Structures of the resultant dye molecules have been confirmed using different spectral techniques such as Mass spectrometry, H-NMR spectroscopy, FT-IR, and UV-Visible spectroscopy.
RESULTS
Thermal stability of the synthesized dyes was also determined. These dyes have been applied to wool and nylon-6 fabrics. Their various fastness properties were examined using ISO standard methods.
CONCLUSION
All the compounds exhibited good to excellent fastness properties. The synthesized dyes and the dyed fabrics were screened biologically against ATCC 6538 and ATCC 10536, resulting in significant antibacterial activities.
Topics: Animals; Humans; Azo Compounds; Spectroscopy, Fourier Transform Infrared; Textiles; Anti-Bacterial Agents; Coloring Agents
PubMed: 37005534
DOI: 10.2174/1573406419666230331083942 -
Chemical Communications (Cambridge,... Sep 2021We report the synthesis and characterisation of a photoswitchable DFG-out kinase inhibitor. Photocontrol of the target kinase in both enzymatic and living cell assays is...
We report the synthesis and characterisation of a photoswitchable DFG-out kinase inhibitor. Photocontrol of the target kinase in both enzymatic and living cell assays is demonstrated.
Topics: Azo Compounds; Drug Development; HEK293 Cells; Humans; Molecular Structure; Protein Kinase Inhibitors; Protein Kinases
PubMed: 34505602
DOI: 10.1039/d1cc04125h -
Mutation Research Jan 1983
Review
Topics: Animals; Azo Compounds; Carcinogens; Cell Line; Cycasin; DNA Repair; Humans; Methylazoxymethanol Acetate; Mitosis; Mutagenicity Tests; Mutagens; Mutation; Saccharomyces cerevisiae; Salmonella typhimurium
PubMed: 6338356
DOI: 10.1016/0165-1110(83)90018-0 -
Bioresource Technology Oct 2016A continuous stirred tank reactor with built-in bioelectrochemical system (CSTR-BES) was developed for azo dye Alizarin Yellow R (AYR) containing wastewater treatment....
A continuous stirred tank reactor with built-in bioelectrochemical system (CSTR-BES) was developed for azo dye Alizarin Yellow R (AYR) containing wastewater treatment. The decolorization efficiency (DE) of the CSTR-BES was 97.04±0.06% for 7h with sludge concentration of 3000mg/L and initial AYR concentration of 100mg/L, which was superior to that of the sole CSTR mode (open circuit: 54.87±4.34%) and the sole BES mode (without sludge addition: 91.37±0.44%). The effects of sludge concentration and sodium acetate (NaAc) concentration on azo dye decolorization were investigated. The highest DE of CSTR-BES for 4h was 87.66±2.93% with sludge concentration of 12,000mg/L, NaAc concentration of 2000mg/L and initial AYR concentration of 100mg/L. The results in this study indicated that CSTR-BES could be a practical strategy for upgrading conventional anaerobic facilities against refractory wastewater treatment.
Topics: Azo Compounds; Bioreactors; Coloring Agents; Sewage; Water Purification
PubMed: 27497830
DOI: 10.1016/j.biortech.2016.07.135 -
Ultrasonics Sonochemistry Feb 2007A combination of ultrasound and exfoliated graphite has been used to treat wastewater containing direct scarlet 4BS for colour removal and for the reduction of...
A combination of ultrasound and exfoliated graphite has been used to treat wastewater containing direct scarlet 4BS for colour removal and for the reduction of absorption at a wavelength of 242 nm. The results show that the ultrasound/exfoliated graphite process is effective in removing direct scarlet 4BS from aqueous solution. Furthermore, it can achieve better results than either exfoliated graphite or ultrasound alone.
Topics: Azo Compounds; Dose-Response Relationship, Radiation; Graphite; Radiation Dosage; Solutions; Sonication; Water; Water Pollutants, Chemical; Water Purification
PubMed: 16750651
DOI: 10.1016/j.ultsonch.2006.04.005