63-74-1Relevant articles and documents
Electrochemical Behavior of Azobenzene-4,4'-disulfonamide at Pyrolitic Graphite Electrode
Goyal, R. N.,Srivastava, Amit Kumar
, p. 205 - 211 (1993)
The electrochemical reduction of azobenzene-4,4'-disulfonamide (1), an oxidation product of sulfanilamide, has been studied at Pyrolytic graphite electrode, over a wide pH range of 3.0 to 10.6 in the Britton Robinson buffers, by electrochemical and spectroscopic techniques.Under cyclic voltammetric conditions the 2e-, 2H+ reduction of this compound was found to give hydrazobenzene-4,4'-disulfonamide which has been characterised using IR, mp, mass and NMR spectra.Under controlled potential electrolysis, the presence of two electron withdrawing -SO2NH2 groups was found to cause the slow disproportionation -3 s-1> of the hydrazo compound and sulfanilamide has been found as the major product of reduction.A plausible mechanism for the ECE reduction of 1 is suggested.
Green process synthesis method of sulfanilamide
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Paragraph 0019, (2021/09/04)
The invention discloses a green process synthesis method of sulfanilamide, and belongs to the technical field of organic synthesis. The method comprises the following steps: carrying out amination reaction on an acetamidobenzene sulfonyl chloride dry product and ammonia gas in the presence of an anhydrous solvent; the method has the advantages that the solvent can be recycled by adjusting the reaction temperature and changing the process method, the yield is improved, the environment-friendly treatment cost is reduced, the reaction condition is mild, the operation is convenient, and the method is suitable for industrial production; p-acetamidobenzene sulfonyl chloride is prevented from being decomposed when encountering water, side reactions are reduced, and the yield is increased; during subsequent treatment and pH adjustment, a proper acid is used, so that generation of mixed high-salinity wastewater is avoided; ammonia gas is used for replacing ammonia water, so that raw materials are saved, the alkali consumption is reduced by 63%, and no various high-salinity wastewater is generated; operation is simple, automation degree is high, and waste water is little; the yield of the sulfanilamide can be increased, and the yield of the sulfanilamide is increased to 96.2%-98.3%.
Beyond Basicity: Discovery of Nonbasic DENV-2 Protease Inhibitors with Potent Activity in Cell Culture
Kühl, Nikos,Leuthold, Mila M.,Behnam, Mira A. M.,Klein, Christian D.
supporting information, p. 4567 - 4587 (2021/05/06)
The viral serine protease NS2B-NS3 is one of the promising targets for drug discovery against dengue virus and other flaviviruses. The molecular recognition preferences of the protease favor basic, positively charged moieties as substrates and inhibitors, which leads to pharmacokinetic liabilities and off-target interactions with host proteases such as thrombin. We here present the results of efforts that were aimed specifically at the discovery and development of noncharged, small-molecular inhibitors of the flaviviral proteases. A key factor in the discovery of these compounds was a cellular reporter gene assay for the dengue protease, the DENV2proHeLa system. Extensive structure-activity relationship explorations resulted in novel benzamide derivatives with submicromolar activities in viral replication assays (EC50 0.24 μM), selectivity against off-target proteases, and negligible cytotoxicity. This structural class has increased drug-likeness compared to most of the previously published active-site-directed flaviviral protease inhibitors and includes promising candidates for further preclinical development.
Yeast supported gold nanoparticles: an efficient catalyst for the synthesis of commercially important aryl amines
Krishnan, Saravanan,Patel, Paresh N.,Balasubramanian, Kalpattu K.,Chadha, Anju
supporting information, p. 1915 - 1923 (2021/02/06)
Candida parapsilosisATCC 7330 supported gold nanoparticles (CpGNP), prepared by a simple and green method can selectively reduce nitroarenes and substituted nitroarenes with different functional groups like halides (-F, -Cl, -Br), olefins, esters and nitriles using sodium borohydride. The product aryl amines which are useful for the preparation of pharmaceuticals, polymers and agrochemicals were obtained in good yields (up to >95%) using CpGNP catalyst under mild conditions. The catalyst showed high recyclability (≥10 cycles) and is a robust free flowing powder, stored and used after eight months without any loss in catalytic activity.
Hydroboration reduction reaction of aromatic nitro compounds without transition metal catalysis
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Paragraph 0006; 0077-0080, (2021/07/31)
The invention relates to a hydroboration reduction reaction of aromatic nitro compounds without transition metal catalysis. According to the method, triethyl boron and potassium tert-butoxide are used as catalysts for the first time, and an aromatic nitro compound and pinacol borane which is low in price and easy to obtain can be conveniently catalyzed to be subjected to a hydroboration reduction reaction under mild conditions to prepare aromatic amine products. Compared with a traditional method, the method generally has the advantages that the catalyst is cheap and easy to obtain, operation is convenient, and reaction is safe. The selective hydroboration reduction reaction of the non-transition metal reagent catalyzed aromatic nitro compound and pinacol borane is realized for the first time, and a practical new reaction strategy is provided for laboratory preparation or industrial production of aromatic amine products.
Synthesis of new Copper Catalyst with Pyrazole Based Tridentate Ligand and Study of Its Activity for Azide Alkyne Coupling
Rajeswari, Panneer Selvam,Nagarajan, Rajendran,P, Sujith K,Emmanuvel, Lourdusamy
supporting information, (2020/12/03)
Synthesis of new copper catalyst with pyrazole based tridentate ligand and study of its activity for azide alkyne coupling were investigated by researchers. To a solution of acetyl acetone (2.002 g, 20 mmol), 2- nitrophenylhydrazine in ethanol was added five drops of con. HCl and heated at 50° for 1 hour. After confirming the formation of 3, 5-dimethyl-1-(2-nitrophenyl)- 1H-pyrazole by TLC, ice cooled water was added in to the reaction mixture. The precipitate was filtered, washed with water and then hexane. The product formed as yellow precipitate, that precipitate had been filtered by normal filter paper. The product was recrystallized in ethanol. For synthesis, was suspended in 6 mL of deionized and stirred for 4 h until a clear solution was obtained in 50 ml round bottom flask Cu(OAc) 2. The reaction mixture was diluted with water, filtered, washed sequentially with water, methanol and n-hexane. Then dark greenish blue color crystal were formed and used for the reactions. The solid was crystallized in CH2Cl2 to get crystal whose structure was confirmed by single crystal XRD.
Bio-waste chitosan-derived N-doped CNT-supported Ni nanoparticles for selective hydrogenation of nitroarenes
Advani, Jacky H.,Bajaj, Hari C.,Biradar, Ankush V.,Gawande, Manoj B.,Naikwadi, Dhanaji R.,Ravi, Krishnan
, p. 10431 - 10440 (2020/09/18)
In this study, a facile method for the synthesis of leach proof and earth-abundant non-noble Ni nanoparticles on N-doped carbon nanotubes is reported. The catalyst was synthesized by an impregnation-carbonization method, wherein a Ni-chitosan complex upon carbonization in a 5% H2/N2 atmosphere at 800 °C yielded Ni-containing N-doped CNTs. Chitosan served as a single source of carbon and nitrogen, and the nanotube growth was facilitated by the in situ formed Ni nanoparticles. The nanocatalyst was thoroughly characterized by several techniques; elemental mapping by SEM and TEM analysis confirmed the uniform distribution of Ni nanoparticles on the surface of N-doped CNTs with an average size in the range of 10-15 nm. The catalyst efficiently reduced a variety of nitroarenes (>99%) into their corresponding amines at a moderate pressure (5 bar) and a comparatively lower temperature (80 °C). Furthermore, the easy recovery of the catalyst using an external magnetic field along with high activity and easy recyclability makes the protocol eco-friendly.
Amination method of aromatic compound with electron withdrawing group
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Paragraph 0014; 0019-0020; 0023-0024, (2020/12/30)
The invention belongs to the technical field of organic synthesis, and particularly relates to an amination method of an aromatic compound with an electron withdrawing group. The method specifically comprises the following steps: under the catalysis of a titanium silicalite molecular sieve or a titanium silicalite mesoporous material or a mixture of the titanium silicalite molecular sieve and thetitanium silicalite mesoporous material, carrying out chemical reaction on ammonia gas or ammonia water, a hydrogen peroxide solution and an aromatic compound with an electron withdrawing group to obtain the aromatic amine compound. The method for preparing the aromatic amine compound has the advantages of simple process, no toxic solvent, no metal ion residue, high production efficiency, less three wastes and low cost.
Preparation method for coproducing 3-hydroxyacetophenone and crystallized sulfanilamide
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Paragraph 0045; 0047; 0052-0053; 0059; 0064-0065; 0066; 0071, (2020/08/02)
The invention discloses a preparation method for co-producing 3-hydroxyacetophenone and crystallized sulfanilamide. The preparation method comprises the following steps: S1, taking 3-hydroxybenzoic acid, p-acetamidobenzenesulfonyl chloride and an acid-binding agent for condensation reaction to obtain a substance A; S2, performing acylating chlorination reaction on the substance A and an acylatingchlorination reagent to obtain a substance B; S3, taking the substance B to react with dimethyl malonate, magnesium chloride and triethylamine to obtain a substance C; S4, carrying out decarboxylationreaction on the substance C and an acidic substance, carrying out primary filtration, carrying out ammonolysis reaction on a primary filter cake and an aminating agent, adding an alkaline substance,carrying out amino deprotection reaction, crystallizing, carrying out secondary filtration, and taking a secondary filter cake to obtain crystallized sulfanilamide; and adjusting the pH value of the secondary filtrate to be less than 7, and crystallizing to obtain 3-hydroxyacetophenone. According to the preparation method, 3-hydroxybenzoic acid and p-acetamidobenzenesulfonyl chloride are taken asraw materials, two substances, namely 3-hydroxyacetophenone and crystallized sulfanilamide, are synchronously prepared, and the yield is relatively good.
Harnessing Endogenous Formate for Antibacterial Prodrug Activation by in cellulo Ruthenium-Mediated Transfer Hydrogenation Reaction
Ang, Wee Han,Shen, Linghui,Weng, Cheng
supporting information, p. 9314 - 9318 (2020/04/29)
The abundance and evolving pathogenic behavior of bacterial microorganisms give rise to antibiotic tolerance and resistance which pose a danger to global public health. New therapeutic strategies are needed to keep pace with this growing threat. We propose a novel approach for targeting bacteria by harnessing formate, a cell metabolite found only in particular bacterial species, to activate an antibacterial prodrug and selectively inhibit their growth. This strategy is premised on transfer hydrogenation reaction on a biorthogonal substrate utilizing native formate as the hydride source as a means of uncaging an antibacterial prodrug. Using coordination-directed 3-component assembly to prepare a library of 768 unique Ru–Arene Schiff-base complexes, we identified several candidates that efficiently reduced sulfonyl azide functional group in the presence of formate. This strategy paves the way for a new approach of targeted antibacterial therapy by exploiting unique bacterial metabolites.
