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Macromolecular Rapid Communications Jan 2018Azobenzene-containing macromolecules (azo-macromolecules) such as azobenzene-containing polymers (azopolymers) and azobenzene-functionalized biomacromolecules are... (Review)
Review
Azobenzene-containing macromolecules (azo-macromolecules) such as azobenzene-containing polymers (azopolymers) and azobenzene-functionalized biomacromolecules are photoswitchable macromolecules. Trans-to-cis photoisomerization in conventional azo-macromolecules is induced by ultraviolet (UV) light. However, UV light cannot penetrate deeply into issue and has a very small fraction in sunlight. Therefore, conventional azo-macromolecules are problematic for biomedical and solar-energy-related applications. In this Feature Article, the strategies for constructing visible and near-infrared (NIR) light-responsive azo-macromolecules are reviewed, and the potential applications of visible- and NIR-light-responsive azo-macromolecules in biomedicine and solar energy conversion are highlighted. The remaining challenges in the field of photoswitchable azo-macromolecules are discussed.
Topics: Azo Compounds; Infrared Rays; Macromolecular Substances; Molecular Structure; Ultraviolet Rays
PubMed: 28643895
DOI: 10.1002/marc.201700220 -
Mini Reviews in Medicinal Chemistry 2021Azo molecules possess the characteristic azo bond (-N=N-) and are considered fascinating motifs in organic chemistry. Since the last century, these brightly colored... (Review)
Review
Azo molecules possess the characteristic azo bond (-N=N-) and are considered fascinating motifs in organic chemistry. Since the last century, these brightly colored compounds have been widely employed as dyes across several industries in applications for printing, food, paper, cosmetics, lasers, electronics, optics, material sciences, etc. The discovery of Prontosil, an antibacterial drug, propelled azo compounds into the limelight in the field of medicinal chemistry. Subsequent discoveries including Phenazopyridine, Basalazide, and Sulfasalazine enabled azo compounds to occupy a significant role in the drug market. Furthermore, azo compounds have been employed as antibacterial, antimalarial, antifungal, antioxidant, as well as antiviral agents. The metabolic degradation of many azo dyes can induce liver problems if ingested, posing a safety concern and limiting their application as azo dyes in medicinal chemistry. However, azo dyes remain particularly significant for applications in cancer chemotherapy. Recently, a paradigm shift has been observed in the use of azo dyes: from medicinal chemistry to biomedical sciences. The latter benefits from azo dye application are related to imaging, drug delivery, photo-pharmacology and photo switching. Herein, we have compiled and discussed recent works on azo dye compounds obtained so far, focusing on their medicinal importance and future prospects.
Topics: Azo Compounds; Biomedical Research; Chemistry, Pharmaceutical; Drug Delivery Systems; Humans; Molecular Structure
PubMed: 33231147
DOI: 10.2174/1389557520999201123210025 -
International Journal of Environmental... Apr 2022Azo dyes have become a staple in various industries, as colors play an important role in consumer choices. However, these dyes pose various health and environmental... (Review)
Review
Azo dyes have become a staple in various industries, as colors play an important role in consumer choices. However, these dyes pose various health and environmental risks. Although different wastewater treatments are available, the search for more eco-friendly options persists. Bioremediation utilizing microorganisms has been of great interest to researchers and industries, as the transition toward greener solutions has become more in demand through the years. This review tackles the health and environmental repercussions of azo dyes and its metabolites, available biological approaches to eliminate such dyes from the environment with a focus on the use of different microorganisms, enzymes that are involved in the degradation of azo dyes, and recent trends that could be applied for the treatment of azo dyes.
Topics: Azo Compounds; Biodegradation, Environmental; Coloring Agents
PubMed: 35457607
DOI: 10.3390/ijerph19084740 -
Chemistry (Weinheim An Der Bergstrasse,... Jul 2023Multiple triggered-release strategies are widely utilized to control the release of caged target molecules. Among them, photocages with conditional triggers provide...
Multiple triggered-release strategies are widely utilized to control the release of caged target molecules. Among them, photocages with conditional triggers provide extra layers of control in photorelease. In this work, a series of pH-responsive photocages was designed that could be triggered under irradiation and specific intracellular pH values. pH-sensitive phenolic groups were conjugated with o-nitrobenzyl (oNB) to form azo-phenolic NPX photocages with tunable pKa. These azo-phenol-based oNB photocages showed differentiable photoreleasing profiles at pH 5.0, 7.2 and 9.0. By attaching fluorogenic cargos, it was shown that one of the photocages, NPdiCl, could be used to differentiate between acidic pH 5.0 and neutral pH 7.2 in cells under artificial pH conditions. Finally, NPdiCl was identified as a promising pH-responsive photocage for photoreleasing cargo inside acidic tumor cells.
Topics: Hydrogen-Ion Concentration; Phenol; Phenols; Azo Compounds
PubMed: 37154791
DOI: 10.1002/chem.202300884 -
Food and Chemical Toxicology : An... Aug 2023Azo dyes, including Tartrazine, Sunset Yellow, and Carmoisine, are added to foods to provide color, but they have no value with regard to nutrition, food preservation,... (Review)
Review
Azo dyes, including Tartrazine, Sunset Yellow, and Carmoisine, are added to foods to provide color, but they have no value with regard to nutrition, food preservation, or health benefits. Because of their availability, affordability, stability, and low cost, and because they provide intense coloration to the product without contributing unwanted flavors, the food industry often prefers to use synthetic azo dyes rather than natural colorants. Food dyes have been tested by regulatory agencies responsible for guaranteeing consumer safety. Nevertheless, the safety of these colorants remains controversial; they have been associated with adverse effects, particularly due to the reduction and cleavage of the azo bond. Here, we review the features, classification, regulation, toxicity, and alternatives to the use of azo dyes in food.
Topics: Azo Compounds; Tartrazine; Coloring Agents; Food; Food Industry; Food Coloring Agents
PubMed: 37429408
DOI: 10.1016/j.fct.2023.113935 -
Organic & Biomolecular Chemistry Nov 2022Pyrazole is an essential structural component of many pharmaceuticals and agrochemicals. The synthesis of pyrazoles has been a subject of intense research for several... (Review)
Review
Pyrazole is an essential structural component of many pharmaceuticals and agrochemicals. The synthesis of pyrazoles has been a subject of intense research for several decades. Many transformations are now available to conveniently access pyrazoles from readily available starting materials. Conventionally, the synthesis of pyrazoles involves the condensation reaction of hydrazines with 1,3-dicarbonyl compounds or their synthetic equivalents and 1,3-dipolar cycloaddition reactions of diazo compounds with dipolarophiles. The present review provides comprehensive information on the development of synthetic approaches to access pyrazoles [3 + 2] cycloaddition reactions of diazo compounds and their synthetic equivalents.
Topics: Cycloaddition Reaction; Azo Compounds; Pyrazoles; Hydrazines
PubMed: 36331498
DOI: 10.1039/d2ob01918c -
Organic & Biomolecular Chemistry Feb 2022Light-switchable inhibitors of the enzyme β-glucocerebrosidase (GCase) have been developed by anchoring a specific azasugar to a dihydroazulene or an azobenzene...
Light-switchable inhibitors of the enzyme β-glucocerebrosidase (GCase) have been developed by anchoring a specific azasugar to a dihydroazulene or an azobenzene responsive moiety. Their inhibitory effect towards human GCase, before and after irradiation are reported, and the effect on thermal denaturation of recombinant GCase and cytotoxicity were studied on selected candidates.
Topics: Azo Compounds; Azulenes; Cell Line; Cell Survival; Enzyme Inhibitors; Glucosylceramidase; Humans; Light; Molecular Structure; Photochemical Processes
PubMed: 35107482
DOI: 10.1039/d1ob02159a -
Organic Letters Jun 2021Azoheteroarenes make up an emerging class of photoswitchable compounds with unique photophysical properties and advantages over traditional azobenzenes. Therefore,...
Azoheteroarenes make up an emerging class of photoswitchable compounds with unique photophysical properties and advantages over traditional azobenzenes. Therefore, methods for synthesizing azoheteroarenes are highly desirable. Here, we utilize azide-alkyne click chemistry to access arylazo-1,2,3-triazoles, a previously unexplored class of azoheteroarenes that exhibit high thermal stabilities and near-quantitative bidirectional photoconversion. Controlling the catalyst or 1,3-dipole grants access to both regioisomeric arylazotriazoles and arylazoisoxazoles, highlighting the versatility of our approach.
Topics: Alkynes; Azides; Azo Compounds; Catalysis; Click Chemistry; Molecular Structure; Triazoles
PubMed: 34019429
DOI: 10.1021/acs.orglett.1c01230 -
ChemMedChem Aug 2020Three photoswitchable tetrapeptides, based on a known synthetic antibacterial, were designed and synthesized to determine activity against Staphylococcus aureus. Each...
Three photoswitchable tetrapeptides, based on a known synthetic antibacterial, were designed and synthesized to determine activity against Staphylococcus aureus. Each peptide contains an azobenzene photoswitch incorporated into either the N-terminal side chain (1), C-terminal side chain (2), or the C-terminus (3) to allow reversible switching between cis- and trans-enriched photostationary states. Biological assays revealed that the C-terminus azobenzene (3) possessed the most potent antibacterial activity, with an MIC of 1 μg/mL. In this study, net positive charge, hydrophobicity, position of the azobenzene, secondary structure, and amphiphilicity were all found to contribute to antibacterial activity, with each of these factors likely facilitating the peptide to disrupt the negatively charged bacterial lipid membrane. Hence, these short photoswitchable antibacterial tetrapeptides provide insights for the future design and synthesis of antibiotics targeting S. aureus.
Topics: Anti-Bacterial Agents; Azo Compounds; Dose-Response Relationship, Drug; Microbial Sensitivity Tests; Molecular Structure; Peptides; Staphylococcus aureus; Structure-Activity Relationship
PubMed: 32558320
DOI: 10.1002/cmdc.202000280 -
Macromolecular Rapid Communications Jan 2018The development of stimuli-responsive polymers is among the key goals of modern materials science. The structure and properties of such switchable materials can be... (Review)
Review
The development of stimuli-responsive polymers is among the key goals of modern materials science. The structure and properties of such switchable materials can be designed to be controlled via various stimuli, among which light is frequently the most powerful trigger. Light is a gentle energy source that can target materials remotely, and with extremely high spatial and temporal resolution easily and cheaply. Reversible light-control over molecular mechanical properties in particular has in recent years attracted great interest due to potential applications as optical-to-mechanical conversion actuators and 'devices', enabling 'molecular robotic machines'. In this review, some recent examples and emerging trends in this exciting field of research are highlighted, covering a wide variety of polymer hosts that contain azobenzene photo-reversible switches. It is hoped that this review will help stimulate more interest towards the development of light-reversible materials for energy harvesting and conversion, and their successful incorporation into a wide variety of current and future high-tech applications in devices.
Topics: Azo Compounds; Molecular Structure; Polymers; Sunlight
PubMed: 28692758
DOI: 10.1002/marc.201700253