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Molecules (Basel, Switzerland) Jun 2020Three series of azo dyes derived from 2-amino-5-aryl-1,3,4-thiadiazoles and aniline, -dimethylaniline and phenol were synthesized in high yields by a conventional...
Three series of azo dyes derived from 2-amino-5-aryl-1,3,4-thiadiazoles and aniline, -dimethylaniline and phenol were synthesized in high yields by a conventional diazotization-coupling sequence. The chemical structures of the prepared compounds were confirmed by H-NMR, C-NMR, IR, UV-Vis spectroscopy, mass spectrometry and elemental analysis. In addition, the X-ray single crystal structure of a representative azo dye was presented. For explicit determination of the influence of a substituent on radiation absorption in UV-Vis range, time-dependent density functional theory calculations were performed.
Topics: Azo Compounds; Models, Molecular; Molecular Structure; Spectrophotometry, Ultraviolet; Thiadiazoles
PubMed: 32570910
DOI: 10.3390/molecules25122822 -
ACS Chemical Biology Nov 2011Here I show that a "pure" research project, seemingly totally lacking in practical application when it was first published, can years later spark a whole new scientific... (Review)
Review
Here I show that a "pure" research project, seemingly totally lacking in practical application when it was first published, can years later spark a whole new scientific field with the potential to revolutionize clinical practice. A 1961 publication describing adducts of nitric oxide (NO) with certain nucleophiles attracted little notice at the time, but later work showing that the adducts could be hydrolyzed to regenerate the NO in bioactive form has provided the foundation for a host of biomedical applications. Crucial to the discovery of widely used tools for studying NO's chemical biology as well as for the design of a variety of promising therapeutic advances has been the increasingly detailed understanding of the physicochemical properties of these "diazeniumdiolates" (also known as NONOates).
Topics: Animals; Azo Compounds; Biomedical Research; Humans; Nitric Oxide; Protons; Spectrum Analysis
PubMed: 21932836
DOI: 10.1021/cb200274r -
Chembiochem : a European Journal of... Jun 2006The photoinduced isomerization of azobenzene between the extended (trans) and compact (cis) conformations is reversibly triggered by light of two differing wavelengths.... (Review)
Review
The photoinduced isomerization of azobenzene between the extended (trans) and compact (cis) conformations is reversibly triggered by light of two differing wavelengths. The resulting changes in molecular geometry have been extensively utilized to photoswitch transformations in chemical species reversibly for applications in optoelectronic devises as well as to photocontrol conformational states in (bio)polymers. The high isomerization yield, remarkable photostability and ultrafast kinetics (few ps) of azobenzene are well suited for the design of small, defined model systems that allow detailed folding studies to be carried out both experimentally and theoretically on the same molecules. In our and other laboratories such systems were recently obtained with cyclic peptides of defined conformational preferences as well as with alpha-helical and beta-hairpin peptides. These should, by comparison of simulation and experiment, permit an assessment and improvement of the theoretical description on the one hand and a detailed interpretation of the ultrafast conformational dynamics on the other. The phototriggered changes in conformational states lead to concurrent changes in biophysical properties that can be exploited in the photocontrol of biochemical and biological events, as exemplarily discussed with redox-active cyclic bis-cysteinyl peptides and receptor ligands.
Topics: Azo Compounds; Chromogenic Compounds; Light; Models, Chemical; Oxidation-Reduction; Peptides; Protein Conformation; Stereoisomerism
PubMed: 16642526
DOI: 10.1002/cbic.200500531 -
Electrophoresis Jan 2005Newly prepared azo compounds and several commercially available indicators were investigated for their applicability as colored isoelectric point (pI) markers for...
Newly prepared azo compounds and several commercially available indicators were investigated for their applicability as colored isoelectric point (pI) markers for isoelectric focusing (IEF) in the acidic range below pH 5. The majority of compounds described here can serve as primary standards since their pI values were determined by UV-VIS spectrophotometry independently IEF and direct measurement with a pH electrode. Subjected to gel IEF they show narrow and well-observable zones of different colors. Finally, our work resulted in suggestion of a color ladder composed of pI markers covering the pH range from 1.5 to 4.7.
Topics: Azo Compounds; Coloring Agents; Hydrogen-Ion Concentration; Isoelectric Focusing; Isoelectric Point
PubMed: 15624139
DOI: 10.1002/elps.200406088 -
Journal of Medicinal Chemistry Nov 1970
Topics: Antifungal Agents; Azo Compounds; Fungi; Griseofulvin; Microbial Sensitivity Tests
PubMed: 5479880
DOI: 10.1021/jm00300a059 -
BioMed Research International 2013In the present paper, we report the synthesis and pharmacological evaluation of a new series of azo compounds with different groups (1-naphthol, 2-naphthol, and...
In the present paper, we report the synthesis and pharmacological evaluation of a new series of azo compounds with different groups (1-naphthol, 2-naphthol, and N,N-dimethylaniline) and trifluoromethoxy and fluoro substituents in the scaffold. All synthesized compounds (5a-5f) showed the most potent mushroom tyrosinase inhibition (IC₅₀ values in the range of 4.39 ± 0.76-1.71 ± 0.49 µM), comparable to the kojic acid, as reference standard inhibitor. All the novel compounds were characterized by FT-IR, ¹H NMR, ¹³C NMR, and elemental analysis.
Topics: Animals; Azo Compounds; Cell Death; Cell Line, Tumor; Enzyme Inhibitors; Melanins; Mice; Monophenol Monooxygenase; Spectrophotometry, Ultraviolet
PubMed: 24260737
DOI: 10.1155/2013/207181 -
Voprosy Onkologii 1961
Topics: Antineoplastic Agents; Azo Compounds; Humans
PubMed: 14459459
DOI: No ID Found -
Lloydia 1977
Review
Topics: Amines; Animals; Anti-Bacterial Agents; Azaserine; Azo Compounds; Carcinogens; Chemical Phenomena; Chemistry; Cycasin; Diazooxonorleucine; Hydrazines; Hydroxylamines; Nitrosamines; Pteridines; Pyrazoles; Streptozocin; Toxins, Biological
PubMed: 142890
DOI: No ID Found -
Chemistry, An Asian Journal Dec 2014Azo-containing materials have been proven to possess second-order nonlinear optical (NLO) properties, but their third-order NLO properties, which involves two-photon...
Azo-containing materials have been proven to possess second-order nonlinear optical (NLO) properties, but their third-order NLO properties, which involves two-photon absorption (2PA), has rarely been reported. In this study, we demonstrate a significant 2PA behavior of the novel azo chromophore incorporated with bilateral diphenylaminofluorenes (DPAFs) as a π framework. The electron-donating DPAF moieties cause a redshifted π-π* absorption band centered at 470 nm, thus allowing efficient blue-light-induced trans-to-cis photoisomerization with a rate constant of 2.04 × 10(-1) min(-1) at the photostationary state (PSS). The open-aperture Z-scan technique that adopted a femtosecond (fs) pulse laser as excitation source shows an appreciably higher 2PA cross-section for the fluorene-derived azo chromophore than that for common azobenzene dyes at near-infrared wavelength (λex =800 nm). Furthermore, the fs 2PA response is quite uniform regardless of the molecular geometry. On the basis of the computational modeling, the intramolecular charge-transfer (ICT) process from peripheral diphenylamines to the central azo group through a fluorene π bridge is crucial to this remarkable 2PA behavior.
Topics: Azo Compounds; Chromatography, High Pressure Liquid; Fluorine; Magnetic Resonance Spectroscopy; Molecular Structure; Photons; Quantum Theory; Spectrophotometry, Ultraviolet; Spectroscopy, Near-Infrared; Spectrum Analysis, Raman; Stereoisomerism
PubMed: 25294108
DOI: 10.1002/asia.201402896 -
Organic Letters Apr 2021α-Aryl-α-diazoamides were synthesized in two steps under mild conditions. This expeditious route employs Pd-catalyzed C-H arylation of -succinimidyl 2-diazoacetate to...
α-Aryl-α-diazoamides were synthesized in two steps under mild conditions. This expeditious route employs Pd-catalyzed C-H arylation of -succinimidyl 2-diazoacetate to obtain -succinimidyl 2-aryl-2-diazoacetates, followed by aminolysis. The ensuing diazo compounds can esterify carboxyl groups in aqueous solution, and the ester products are substrates for an esterase. The broad scope of the synthetic route enables the continued development of diazo compounds in chemical biology.
Topics: Azo Compounds; Catalysis; Esters; Molecular Structure; Palladium; Stereoisomerism
PubMed: 33818092
DOI: 10.1021/acs.orglett.1c00793