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Chemical Hybridization Approaches Applied to Natural and Synthetic Compounds for the Discovery of Drugs Active Against Neglected Tropical Diseases
Published in Venkatesan Jayaprakash, Daniele Castagnolo, Yusuf Özkay, Medicinal Chemistry of Neglected and Tropical Diseases, 2019
Elena Petricci, Paolo Governa, Fabrizio Manetti
As an example of naphthoquinones, lapachol 3 and the isomeric tricyclic α- and β-lapachone (4 and 5) were extracted from the inner wood of various plants belonging to the Bignoniaceae family, such as Tabebuia avellanedae Lorentz ex Griseb (Figure 2). These compounds caused oxidative damage in trypanosomatids consequent to the release of peroxide and superoxide anions and radicals. Their major limitation was the inactivation in the presence of serum proteins, whose free amino groups can react with the quinone system. Fortunately, this reaction was avoided in the 3-allyl derivative of β-lapachone that proved effective toward trypomastigotes also in the presence of blood (Gonçalves et al. 1980). Design and optimization of naphthoquinone-phenazine hybrids.
The Iodotyrosine Deiodinase Defect
Published in Geraldo Medeiros-Neto, John Bruton Stanbury, Inherited Disorders of the Thyroid System, 2019
Geraldo Medeiros-Neto, John Bruton Stanbury
Activity is stimulated by sodium dithionate in the absence of NADPH,118 and the rate of deiodination is dependent on the quantity of NADPH.114 The dithionate might reduce the flavins. Kusakabe and Miyaki observed that the fraction from a supernatant of homogenate of thyroid migrated toward the anode on electrophoresis, while that solubi-lized from the particulate fraction migrated toward the cathode.115 This suggested that the iodotyrosine deiodinase existed in two isoforms. The removal of the first iodine from diidotyrosine occurs less rapidly than does the deiodination of monoiodotyrosine. Substances such as menadione, methelene blue, and phenazine methosulfate inhibit deiodination even when supplemented with NADPH, probably by accelerating NADPH oxidation.116 Serotonin, acetylcholine, epinephrin, and ferricyanide also inhibit deiodination. Prior injection of nicotinamide into rats stimulates the capacity of liver homogenates to deiodinate DIT, probably by stimulating the concentration of NADPH in the tissue.124 MIT and DIT block tyrosine hydroxylase, but it is not clear what function this might serve, if any.119 It also inhibits dopamine synthesis and induces hyperprolactinemia and hyperaldosteronemia.125-127
Ferrihemoglobin in Normal Blood
Published in Manfred Kiese, Methemoglobinemia: A Comprehensive Treatise, 2019
Standefer et al.392 designed a semiautomated method for determination of ferrihemoglobin reductase NAD which is patterned after the method of Hegesh et al.211 Kajita et al.393 showed that phenazine methosulfate catalyzes the reduction by NADH of human ferrihemoglobin which had passed through a Sephadex G 25 column.
Subtle relationships between Pseudomonas aeruginosa and fungi in patients with cystic fibrosis
Published in Acta Clinica Belgica, 2022
Kaicheng Yan, Hong Yin, Jin Wang, Yun Cai
Phenazines are the metabolite of many microorganisms, many of which have antibiotic activity [28]. It has been reported that PA can produce phenazine, which is a heterocyclic compound with redox activity and naturally occurs in the form of soluble reduction. The aromatic ring is replaced by different functional groups to obtain derivatives of various colors. These natural pigments make pyocyanin green, yellow for phenazine-1-carboxylic acid (PCA) and phenazine-1-carboxylamide, and orange for orange 1-hydroxyphenazine (1-HP) [29,30]. The pigments pyocyanin and 1-HP produced by PA inhibit the germination of AF spores, and 1-HP is the most toxic one of these pigments [31]. Pyocyanin is a well-known virulence factor notably during CF lung infections. Pyocyanin also has antibiotic activity against a wide range of bacteria, and it causes an alteration in functions of neutrophils and lymphocytes, reduction in mucociliary clearance, and inhibition of endothelial–NO interactions. It is toxic to both eukaryotic and bacterial cells, and many mechanisms have been speculated, including induction of oxidative stress and redox activity [32,33]. Other than PCA and pyocyanin, Xu et al. have reported that PA produces small-molecule antimicrobials, including PA06ER10, PA06ER16, PA06ER23, and PA06ER31. They have speculated that these small molecular components may be phenazine analogs because of their similar functions and heavier molecular weights [34].
Synthesis of benzo[a]furo[2, 3-c]phenazine derivatives through an efficient, rapid and via microwave irradiation under solvent-free conditions catalyzed by H3PW12O40@Fe3O4-ZnO for high-performance removal of methylene blue
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2021
Milad Taheri, Razieh Mohebat, Mohammad Hossein Moslemin
In conclusion, the reaction of 2-hydroxynaphthalene-1,4-dione, arylglyoxal, indoles in the presence H3PW12O40@Fe3O4-ZnO MCNPs afforded benzo[a]furo[2, 3-c]phenazine derivatives in excellent yields. The present procedure has the advantage that the reaction is performed under solvent-free conditions using microwave irradiation and the starting material can be used without any activation or modification. In conclusion, a simple and efficient method for the synthesis of phenazines derivatives has been explored. Mild reaction conditions, shorter reaction time, easy and quick isolation of the products, low power consumption, and excellent yields are the main advantages of this method, which makes it an attractive and useful contribution to the present methodologies. The morphology and particle size were investigated using XRD, FESEM, TEM, AFM and VSM analysis reveals the functional compounds present in the nanoparticles. Photocatalytic degradation results show 97% methylene blue degradation under conditions has the best.
Enhancement of iodinin solubility by encapsulation into cyclodextrin nanoparticles
Published in Journal of Enzyme Inhibition and Medicinal Chemistry, 2018
Anthony Prandina, Lars Herfindal, Sylvie Radix, Pål Rongved, Stein O. Døskeland, Marc Le Borgne, Florent Perret
Phenazine is a dibenzo annulated pyrazine present in many natural products1–3 and has become the parent substance of many synthetic bioactive molecules4–6. The broad spectrum of biological activities of phenazine explains the success of research programs exploiting this scaffold. The most striking examples are the targeting of antibiotic-tolerant bacterial biofilms and Mycobacterium tuberculosis by halogenated phenazines7. Other derivatives such as endophenazine G showed activity against community-associated methicillin-resistant Staphylococcus aureus8. Phenazine-1-carboxylic acid derivatives exhibit fungicidal activities9 and finally numerous phenazines were developed as anti-cancer agents10, for example, the novel pyrano[3,2-a]phenazine derivatives demonstrated antiproliferative activity against the HepG2 cancer cell line11.