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Keywords = methyl thioglycolate

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17 pages, 3627 KiB  
Article
Comparative Assessments of New Hair-Straightening Cosmetic Formulations on Wavy Type 2 Hair
by Celso Martins Junior, Matheus Henrique Vieira, Érica Savassa Pinto Cacoci, Ursulandrea Sanches Abelan, Fernanda Daud Sarruf, Cibele Castro Lima and Chung Man Chin
Cosmetics 2024, 11(6), 222; https://doi.org/10.3390/cosmetics11060222 - 16 Dec 2024
Viewed by 2900
Abstract
Hair straighteners are among the most technically complex products to be safely and effectively developed, and this challenge has increased even more with the higher incidence of resistant hair among consumers. This underscores the importance of studying new active ingredients, combinations and carrier [...] Read more.
Hair straighteners are among the most technically complex products to be safely and effectively developed, and this challenge has increased even more with the higher incidence of resistant hair among consumers. This underscores the importance of studying new active ingredients, combinations and carrier formulations to improve performance without compromising safety. In this research, we compared eight hair-straightening formulations with different active ingredients and/or concentrations to develop new, safer and more effective texture modifiers. Eight formulations were developed and compared with each other and to controls (virgin and bleached hair) regarding mechanical and thermal resistance, cuticle morphology, hair shine and fiber diameter. Results showed that all formulations were safe and effective at straightening hair. Specifically, 13.3% and 9.4% ammonium thioglycolate (G03 and G04) were more suitable for wavy and curly hair, 12.5% and 7.9% amino methyl propanol thioglycolate (G05 and G06) for finer or chemically processed hair, 5% and 4% sodium cysteamine (G07 and G08) for curly and tight curly hair to control volume, and 2% and 1% of a combination of ammonium thioglycolate with sodium thioglycolate (G09 and G10) for more resistant wavy and curly hair. Full article
(This article belongs to the Section Cosmetic Formulations)
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13 pages, 1702 KiB  
Article
Synthesis of Thieno[3,2-b]thiophenes from 2,5-Dicarbonyl 3-Nitrothiophenes via Nucleophilic Aromatic Substitution of the Nitro Group with Thiolates
by Roman A. Irgashev and Nikita A. Kazin
Organics 2024, 5(4), 507-519; https://doi.org/10.3390/org5040027 - 7 Nov 2024
Viewed by 1975
Abstract
In this study, we developed an efficient strategy for constructing thieno[3,2-b]thiophene molecules from 3-nitrothiophenes, containing carbonyl fragments at the C-2 and C-5 atoms, by nucleophilic aromatic substitution of the nitro group in these substrates. It was shown that the reaction of [...] Read more.
In this study, we developed an efficient strategy for constructing thieno[3,2-b]thiophene molecules from 3-nitrothiophenes, containing carbonyl fragments at the C-2 and C-5 atoms, by nucleophilic aromatic substitution of the nitro group in these substrates. It was shown that the reaction of 3-nitrothiophene-2,5-dicarboxylates with thiophenols, thioglycolates and 2-mercaptoacetone in the presence of K2CO3 proceeds rapidly via nucleophilic displacement of the nitro group with the formation of 3-sulfenylthiophene-2,5-dicarboxylates. Further treatment of the resulting thiophene-2,5-dicarboxylates, which have -SCH2CO2Alk or -SCH2COMe moiety at C-3 atom, with sodium alcoholates afford obtaining 2,3,5-trisubstituted thieno[3,2-b]thiophene derivatives according to the Dieckman condensation. In turn, the reaction of methyl 5-formyl-4-nitrothiophene-2-carboxylate with methyl thioglycolate or 2-mercaptoacetone in the presence of K2CO3 proceeds to directly form 2,5-disubstituted thieno[3,2-b]thiophenes. Full article
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20 pages, 11990 KiB  
Article
Interactions between Damaged Hair Keratin and Juglone as a Possible Restoring Agent: A Vibrational and Scanning Electron Microscopy Study
by Michele Di Foggia, Paola Taddei, Carla Boga, Benedetta Nocentini and Gabriele Micheletti
Molecules 2024, 29(2), 320; https://doi.org/10.3390/molecules29020320 - 9 Jan 2024
Cited by 4 | Viewed by 2933
Abstract
Juglone, a quinonic compound present in walnut extracts, was proposed as a restoring agent for hair keratin treated with permanent or discoloration processes. The proposed mechanism of restoration by juglone involves the formation of a Michael adduct between the quinone and the thiol [...] Read more.
Juglone, a quinonic compound present in walnut extracts, was proposed as a restoring agent for hair keratin treated with permanent or discoloration processes. The proposed mechanism of restoration by juglone involves the formation of a Michael adduct between the quinone and the thiol moieties of cysteine residues. To this purpose, the first part of the present paper involved the spectroscopic study of the product of the reaction between juglone and N-acetyl-L-cysteine as a model compound. IR spectroscopy and Scanning Electron Microscopy (SEM) monitored the chemical and morphological variations induced by applying juglone to hair keratin. In order to simulate the most common hair treatments (i.e., permanent and discoloration), juglone was applied to hair that had been previously treated with a reducing agent, i.e., methyl thioglycolate (MT) or with bleaching agents (based on hydrogen peroxide and persulfates) followed by sodium hydrogen sulfite. IR spectroscopy allowed us to monitor the formation of Michael adducts between juglone and cysteine residues: the Michael adducts’ content was related to the cysteine content of the samples. In fact, MT and sodium hydrogen sulfite favored the reduction of the disulfide bonds and increased the content of free cysteine residues, which can react with juglone. SEM analyses confirmed the trend observed by IR spectroscopy since hair samples treated with juglone adopted a more regular hair surface and more imbricated scales, thus supporting the possible use of juglone as a restoring agent for damaged hair keratins. Full article
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18 pages, 4866 KiB  
Article
Multicomponent Molecular Systems Based on Porphyrins, 1,3,5-Triazine and Carboranes: Synthesis and Characterization
by Victoria M. Alpatova, Evgeny G. Rys, Elena G. Kononova, Ekaterina A. Khakina, Alina A. Markova, Anna V. Shibaeva, Vladimir A. Kuzmin and Valentina A. Ol’shevskaya
Molecules 2022, 27(19), 6200; https://doi.org/10.3390/molecules27196200 - 21 Sep 2022
Cited by 5 | Viewed by 2409
Abstract
2,4,6-Trichloro-1,3,5-triazine (cyanuric chloride) is an excellent coupling reagent for the preparation of highly structured multifunctional molecules. Three component systems based on porphyrin, cyanuric chloride and carborane clusters were prepared by a one-pot stepwise amination of cyanuric chloride with 5-(4-aminophenyl)-10,15,20-triphenylporphyrin, followed by replacement of [...] Read more.
2,4,6-Trichloro-1,3,5-triazine (cyanuric chloride) is an excellent coupling reagent for the preparation of highly structured multifunctional molecules. Three component systems based on porphyrin, cyanuric chloride and carborane clusters were prepared by a one-pot stepwise amination of cyanuric chloride with 5-(4-aminophenyl)-10,15,20-triphenylporphyrin, followed by replacement of the remaining chlorine atoms with carborane S- or N-nucleophiles. Some variants of 1,3,5-triazine derivatives containing porphyrin, carborane and residues of biologically active compounds such as maleimide, glycine methyl ester as well as thioglycolic acid, mercaptoethanol and hexafluoroisopropanol were also prepared. A careful control of the reaction temperature during the substitution reactions will allow the synthesis of desired compounds in a good to high yields. The structures of synthesized compounds were determined with UV-vis, IR, 1H NMR, 11B NMR, MALDI-TOF or LC-MS spectroscopic data. The dark and photocytotoxicity as well as intracellular localization and photoinduced cell death for compounds 8, 9, 17, 18 and 24 were evaluated. Full article
(This article belongs to the Special Issue Design and Synthesis of Macrocyclic Compounds)
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12 pages, 3088 KiB  
Article
Artificial, Photoinduced Activation of Nitrogenase Using Directed and Mediated Electron Transfer Processes
by Matan M. Meirovich, Oren Bachar and Omer Yehezkeli
Catalysts 2020, 10(9), 979; https://doi.org/10.3390/catal10090979 - 31 Aug 2020
Cited by 5 | Viewed by 4016
Abstract
Nitrogenase, a bacteria-based enzyme, is the sole enzyme that is able to generate ammonia by atmospheric nitrogen fixation. Thus, improved understanding of its utilization and developing methods to artificially activate it may contribute to basic research, as well as to the design of [...] Read more.
Nitrogenase, a bacteria-based enzyme, is the sole enzyme that is able to generate ammonia by atmospheric nitrogen fixation. Thus, improved understanding of its utilization and developing methods to artificially activate it may contribute to basic research, as well as to the design of future artificial systems. Here, we present methods to artificially activate nitrogenase using photoinduced reactions. Two nitrogenase variants originating from Azotobacter vinelandii were examined using photoactivated CdS nanoparticles (NPs) capped with thioglycolic acid (TGA) or 2-mercaptoethanol (ME) ligands. The effect of methyl viologen (MV) as a redox mediator of hydrogen and ammonia generation was tested and analyzed. We further determined the NPs conductive band edges and their effect on the nitrogenase photoactivation. The nano-biohybrid systems comprising CdS NPs and nitrogenase were further imaged by transmission electron microscopy, visualizing their formation for the first time. Our results show that the ME-capped CdS NPs–nitrogenase enzyme biohybrid system with added MV as a redox mediator leads to a five-fold increase in the production of ammonia compared with the non-mediated biohybrid system; nevertheless, it stills lag behind the natural process rate. On the contrary, a maximal hydrogen generation amount was achieved by the αL158C MoFe-P and the ME-capped CdS NPs. Full article
(This article belongs to the Special Issue NanoBio Hybrids and Photocatalysis)
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15 pages, 605 KiB  
Article
Purification of a Lectin from Arisaema erubescens (Wall.) Schott and Its Pro-Inflammatory Effects
by Xian Qiong Liu, Hao Wu, Hong Li Yu, Teng Fei Zhao, Yao Zong Pan and Run Jun Shi
Molecules 2011, 16(11), 9480-9494; https://doi.org/10.3390/molecules16119480 - 14 Nov 2011
Cited by 28 | Viewed by 6254
Abstract
The monocot lectin from the tubers of Arisaema erubescens (Wall.) Schott has been purified by consecutive hydrophobic chromatography and ion exchange chromatography methods. The molecular weight of this A. erubescens lectin (AEL) was determined to be about 12 kDa by high performance liquid [...] Read more.
The monocot lectin from the tubers of Arisaema erubescens (Wall.) Schott has been purified by consecutive hydrophobic chromatography and ion exchange chromatography methods. The molecular weight of this A. erubescens lectin (AEL) was determined to be about 12 kDa by high performance liquid chromatography (HPLC) and sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) methods. AEL could agglutinate rabbit erythrocytes. The haemagglutination activity of AEL was only inhibited by asialofetuin, while monosaccharide did not react. Rat paw edema and neutrophil migration models were used to investigate the pro-inflammatory activity of AEL. AEL (100 and 200 μg/paw) could induce significant rat paw edema. In addition, AEL (100, 200 and 300 μg/mL/cavity) could induce significant and dose-dependent neutrophil migration in the rat peritoneal cavities. Besides, AEL at doses ranging from 100 to 300 μg/mL/cavity could significantly increase the concentration of nitric oxide (NO), prostaglandin E2 (PGE2) and tumor necrosis factor alpha (TNF-α) in peritoneal fluid. As compared with control animals, 75% depletion in the number of resident cells following peritoneal lavage did not reduce the AEL-induced neutrophil migration. However, pre-treatment with 3% thioglycollate which increased the peritoneal macrophage population by 201%, enhanced the neutrophil migration induced by AEL (200 μg/mL/cavity) (p < 0.05). Reduction of peritoneal mast cell population by chronic treatment of rat peritoneal cavities with compound 48/80 (N-methyl-p-methoxyphenethylamine with formaldehyde) did not modify AEL-induced neutrophil migration. The results provided the basis for identifying the toxic components of A. erubescens and AEL could be a new useful tool for pro-inflammatory research. Full article
(This article belongs to the Section Natural Products Chemistry)
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8 pages, 2211 KiB  
Article
Synthese von einigen potentiellen NO-Synthase-Inhibitoren mit Thieno[2,3-b] [1,4l thiazin-Grundgerüst
by M. E. Galanski, N. Böhler and T. Erker
Sci. Pharm. 2001, 69(4), 321-328; https://doi.org/10.3797/scipharm.aut-01-203 - 28 Dec 2001
Cited by 1 | Viewed by 1085
Abstract
The synthesis of thiolactime 4 and first studies on the syntheses of other thiolactimes with different substituted thieno[2,3-b][1,4]thiazine moieties are described as well as the syntheses of structurally modified amidines 10 - 14 with the same basic structure. The thieno[2,3-b][1,4]thiazine derivatives were prepared [...] Read more.
The synthesis of thiolactime 4 and first studies on the syntheses of other thiolactimes with different substituted thieno[2,3-b][1,4]thiazine moieties are described as well as the syntheses of structurally modified amidines 10 - 14 with the same basic structure. The thieno[2,3-b][1,4]thiazine derivatives were prepared by reacting methyl 5-chloro-4-nitro-2-thiophencarboxylate with ethyl thioglycolate followed by reductive cyclisation to 6, which was either first saponified and then treated with Lawesson reagent to obtain thiolactame 8 or directly reacted to thiolactame 9. Reaction of 9 with various amines led to the desired products 10 - 14. which will undergo pharmacological testing on NO synthase inhibiting activities. Full article
10 pages, 3410 KiB  
Article
Synthesis and In Vitro Evaluation of Chitosan-Thioglycolic Acid Conjugates
by Andreas Bernkop-Schnürch and Thorid E. Hopf
Sci. Pharm. 2001, 69(2), 109-118; https://doi.org/10.3797/scipharm.aut-01-12 - 30 Jun 2001
Cited by 59 | Viewed by 2386
Abstract
The cationic thiomer chitosan-thioglycolic acid (TGA) shows excellent mucoadhesive features. In order to deepen the knowledge concerning this new excipient the optimization of its synthesis and a detailed characterization of its properties was the objective of this study Mediated by increasing quantities of
[...] Read more.
The cationic thiomer chitosan-thioglycolic acid (TGA) shows excellent mucoadhesive features. In order to deepen the knowledge concerning this new excipient the optimization of its synthesis and a detailed characterization of its properties was the objective of this study Mediated by increasing quantities of a carbodiimide, thioglycolic acid was covalently attached to chitosan forming amide bonds with the primary amino groups of the polymer Determined with Ellman's reagent, 38 ± 3, 104 ± 2, 685 ± 43, and 885 ± 7 pmol thiol groups (n=3; ± SD) were bound per gram polymer at carbodiimide concentrations of 50, 75, 100, and 125 mM, respectively. The immobilized thiol groups displayed a comparatively higher reactivity to form disulfide bonds than the thiol groups in a corresponding mixture of chitosan and free unconjugated TGA. In an aqueous 0.5% (rnlv) chitosan-TGA gel 59 ± 5% of the thiol groups formed disulfide bonds within 6 hours at pH 6.0, whereas merely 5 ± 3% were oxidized in the corresponding physical mixture of chitosan and TGA. Diffusion studies showed that the modified polymer was capable of binding cysteine and cysteine methyl ester. The result supports the theory that the improved mucoadhesive properties of thiolated chitosan are based on the formation of disulfide bonds with cysteine moieties of mucus glycoproteins. Because of its availability via an efficient synthetic pathway and its mucoadhesive properties based on the capability to bind cysteine subunits, chitosan-TGA seems to be a promising new excipient for various drug delivery systems.
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