Phenanthridines. III. Syntheses of 9-bromophenanthridine and 7-bromophenanthridine by Pschorr reactions with sulphonamides derived from N-p-bromobenzyl- and N-o-bromobenzyl-o-phenylenediamines, and a new route to N-sulphonylcarbazoles

1964 ◽  
Vol 17 (12) ◽  
pp. 1406 ◽  
Author(s):  
JL Huppatz ◽  
WHF Sasse
Keyword(s):  
Sodium Nitrite ◽  
Sulphonic Acid ◽  
High Yields ◽  
Hydrolysis Of ◽  
By Products ◽  
Phenanthridine Derivative

9-Bromophenanthridine (Ic) has been prepared by oxidative hydrolysis of 9-bromo-5-p-toluenesulphonyl-j,8-dihydrophenanthridine (IIc), which is one of the products of the copper-catalysed decomposition of diazotized N-p-bromobenzy1.N-p- toluenesulphonyl-o-phenylenediamine (IIIc). 7-Bromophenanthridine (Ie) was similarly synthesized from N-o-bromobenzyl-N-methanesulphonyl-o-phenylenediamine (IIIe) by way of 9-bromo-5-methanesulphonyl-5,6-dihydrophenanthridine (IIe). The decomposition of diazotized o-bromobenzyl-N-p-toluenesulphonyl-o- phenylenediamine (IIId) did not yield the corresponding phenanthridine derivative (IId). By-products formed in the cyclization of (IIIc) include 2-p-bromobenzylamino-4'-methylbiphenyl (Vc), 4-bromo-2'-p-toluenesulphonamidobiphenyl (VIc), and N-p-bromobenzyl-2-amino-5'-methylbiphenyl-2'-sulphonic acid sultam (IVc). The amine (IIId) gave 2-o-bromobenzylamino-4'-methylbiphenyl (Vd), 2-bromo-2'-p-toluenesulphonamidobiphenyl (VId), N-o-bromobenzyl-2-amino-5'-methylbiphenyl- 2'-sulphonic acid sultam (IVd), and AT-p-toluenesulphonylcarbazole (VIIa). The amine (IIIe) gave also 2-bromo-2'-methanesulphonamidobiphenyl (VIe) and N-methanesulphonylcarbazole (VIIb). The relative yields of these products depend inter alia on the amount of sodium nitrite used during the inverse diazotization prior to the addition of copper. Under the influence of cuprous compounds the 2-amino-2'-bromobiphenyls (VId) and (VIe) are converted in high yields to the carbazoles (VIIa) and (VIIb), respectively.

An Efficient Synthesis of 2-Substituted Quinazolin-4(3H)-ones by Using Recyclable Wang Resin Supported Sulfonic Acid Catalyst

2020 ◽  
Vol 17 ◽  
Author(s):  
Kalyani K. ◽  
Srinivasa Reddy Kallam
Keyword(s):  
Sulfonic Acid ◽  
Functional Group ◽  
Acid Catalyst ◽  
Sulphonic Acid ◽  
Isatoic Anhydride ◽  
Efficient Synthesis ◽  
Wang Resin ◽  
Polymer Supported ◽  
High Yields

Abstract:: An efficient synthesis of 2-substituted Quinazolin-4(3H)-ones has been developed from isatoic anhydride with various amidoximes by using recyclable polymer supported sulphonic acid catalyst. Excellent functional group compatibil-ity and high yields are the important features of this protocol.

scholarly journals Generation of 1,2-oxathiolium ions from (arysulfonyl)- and (arylsulfinyl)allenes in Brønsted acids. NMR and DFT study of these cations and their reactions

2018 ◽  
Vol 14 ◽  
pp. 2897-2906 ◽  
Author(s):  
Stanislav V Lozovskiy ◽  
Alexander Yu Ivanov ◽  
Olesya V Khoroshilova ◽  
Aleksander V Vasilyev
Keyword(s):  
Dft Calculations ◽  
Reaction Mechanisms ◽  
Dft Study ◽  
Bronsted Acids ◽  
Allyl Alcohols ◽  
High Yields ◽  
Hydrolysis Of

In strong Brønsted acids (CF3SO3H, FSO3H, D2SO4), (arysulfonyl)allenes (ArSO2–CR1=C=CR2R3) and (arylsulfinyl)allenes (ArSO–CR1=C=CR2R3) undergo cyclization into the corresponding stable 1,2-oxathiolium ions, which were studied by means of NMR and DFT calculations. Quenching of solutions of these cations with low nucleophilic media, aqueous HCl, leads to their deprotonation with a stereoselective formation of (arysulfonyl)butadienes (for instance, ArSO2–CR1=C–C(Me)=CH2, for R2 = R3 = Me, yields of 87–98%). Reactions of (arysulfonyl)allenes in the system TfOH (0.1 equiv)–HFIP (hexafluoropropan-2-ol) followed by hydrolysis give rise to allyl alcohols (ArSO2–CR1=CH–C(OH)R2R3, yields of 78–99%). Reflux of solutions of (arysulfonyl)allenes in the presence of TfOH (1 equiv) in 1,2-dichlorobenzene leads to the cyclization into thiochromene 1,1-dioxides in high yields. Under the action of TfOH or AlX3 (X = Cl, Br) followed by hydrolysis of reaction mixtures, (arylsulfinyl)allenes give allyl alcohols (ArSO2–CR1=CH–C(OH)R2R3). Plausible reaction mechanisms have been proposed for all studied reactions.

FTIR as a rapid tool for monitoring molecular weight distribution during enzymatic protein hydrolysis of food processing by-products

2017 ◽  
Vol 9 (29) ◽  
pp. 4247-4254 ◽  
Author(s):  
Sileshi Gizachew Wubshet ◽  
Ingrid Måge ◽  
Ulrike Böcker ◽  
Diana Lindberg ◽  
Svein Halvor Knutsen ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Molecular Weight Distribution ◽  
Weight Distribution ◽  
Food Processing ◽  
Protein Hydrolysis ◽  
Multivariate Approach ◽  
Hydrolysis Of ◽  
By Products ◽  
Rapid Tool

An FTIR-based multivariate approach is developed for monitoring molecular weight distribution during enzymatic protein hydrolysis of byproducts.

scholarly journals Conversion of Fructose to HMF in a Continuous Fixed Bed Reactor with Outstanding Selectivity

Molecules ◽  
2018 ◽  
Vol 23 (7) ◽  
pp. 1802 ◽  
Author(s):  
Eric Weingart ◽  
Sarah Tschirner ◽  
Linda Teevs ◽  
Ulf Prüße
Keyword(s):  
Large Scale ◽  
Continuous Process ◽  
Fixed Bed ◽  
Fixed Bed Reactor ◽  
Water Addition ◽  
Batch Systems ◽  
Formation Conditions ◽  
High Yields ◽  
Optimized Conditions ◽  
By Products

5-Hydroxymethylfurfural (HMF) is a very promising component for bio-based plastics. Efficient synthesis of HMF from biomass is still challenging because of fast degradation of HMF to by-products under formation conditions. Therefore, different studies, conducted mainly in monophasic and biphasic batch systems with and without water addition have been published and are still under investigation. However, to produce HMF at a large scale, a continuous process is preferable. Until now, only a few studies have been published in this context. In this work, it is shown that fluorous alcohol hexafluoroisopropanol (HFIP) can act as superior reaction solvent for HMF synthesis from fructose in a fixed bed reactor. Very high yields of 76% HMF can be achieved in this system under optimized conditions, whilst the catalyst is very stable over several days. Such high yields are only described elsewhere with high boiling reaction solvents like dimethylsulfoxide (DMSO), whereas HFIP with a boiling point of 58 °C is very easy to separate from HMF.

scholarly journals Tomato as Potential Source of Natural Additives for Meat Industry. A Review

Antioxidants ◽  
2020 ◽  
Vol 9 (1) ◽  
pp. 73 ◽  
Author(s):  
Rubén Domínguez ◽  
Patricia Gullón ◽  
Mirian Pateiro ◽  
Paulo E. S. Munekata ◽  
Wangang Zhang ◽  
...  
Keyword(s):  
Organic Solvents ◽  
Meat Products ◽  
Natural Antioxidants ◽  
Economic Problem ◽  
Meat Industry ◽  
Overall Acceptability ◽  
High Yields ◽  
Promising Source ◽  
By Products ◽  
Natural Additives

Tomato industry produces huge amounts of by-products that represent an environmental and economic problem. However, these by-products contain multiple bioactive compounds, which would make them a renewable source for obtaining natural antioxidants and colourants (carotenoids). This is in line with the preferences of the current consumer who demands more natural and healthy products. However, the lipophilic character of carotenoids means that their extraction must be carried out using toxic organic solvents. To overcome environmental and health problems of organic solvents, the application of supercritical fluid extraction (SFE) for the extraction of lipophilic compounds such as lycopene was used successfully, achieving yields similar to those obtained with conventional techniques. Nonetheless, the extraction conditions must be carefully selected, to obtain high yields and at the same time maintain a high antioxidant capacity. On the other hand, the use of tomato and tomato extracts as natural additives in meat products are reduced in comparison with other natural antioxidant/colourant extracts. However, different researches conclude that the use of tomato improved nutritional quality, reduced lipid oxidation and increased stability during the shelf-life period of meat products, while retaining or increasing sensory properties and overall acceptability, which converts tomato by-products into a promising source of natural additives.

scholarly journals Reduce, Reuse and Recycle in Protein Chromatography: Development of an Affinity Adsorbent from Waste Paper and Its Application for the Purification of Proteases from Fish By-Products

Biomolecules ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 822
Author(s):  
Georgios E. Premetis ◽  
Nikolaos E. Labrou
Keyword(s):  
Sparus Aurata ◽  
Single Step ◽  
Precipitation Method ◽  
Equilibrium Studies ◽  
Kinetics Of Adsorption ◽  
Affinity Ligand ◽  
Affinity Adsorbent ◽  
Cellulose Microfibers ◽  
High Yields ◽  
By Products

In the present study, we report the development of a cellulose-based affinity adsorbent and its application for the purification of proteases from fish by-products. The affinity adsorbent was synthesized using cellulose microfibers as the matrix, isolated from recycled newspapers using the acid precipitation method. As an affinity ligand, the triazine dye Cibacron Blue 3GA (CB3GA) was used and immobilized directly onto the cellulose microfibers. Absorption equilibrium studies and frontal affinity chromatography were employed to evaluate the chromatographic performance of the adsorbent using as model proteins bovine serum albumin (BSA) and lysozyme (LYS). Absorption equilibrium studies suggest that the adsorption of both proteins obeys the Langmuir isotherm model. The kinetics of adsorption obey the pseudo-second-order model. The affinity adsorbent was applied for the development of a purification procedure for proteases from Sparus aurata by-products (stomach and pancreas). A single-step purification protocol for trypsin and chymotrypsin was developed and optimized. The protocol afforded enzymes with high yields suitable for technical and industrial purposes.

Utilization of Silica from Indonesian Solid Wastes as Catalyst Materials

2020 ◽  
Vol 849 ◽  
pp. 72-77
Author(s):  
Firman Kurniawansyah ◽  
Amila D. Istiqomah ◽  
Aisyah J. Malahayati ◽  
Himawan Tri Bayu Murti Petrus ◽  
Achmad Roesyadi
Keyword(s):  
Acidic Solution ◽  
Agricultural Waste ◽  
Sulphuric Acid Solution ◽  
Solid Catalyst ◽  
Glucose Yield ◽  
Active Metal ◽  
Alternative Sources ◽  
Hydrolysis Of ◽  
Seaweed Industry ◽  
By Products

Synthesizing materials can be attempted by utilizing alternative sources such as wastes or disposed/by-products of certain activities. In this article, exploration of silica from agricultural waste and from geothermal sludgefor production of silica catalysts, are presented. The first silica catalyst was synthesized from rice husk. The husk was initially heated until silica ashes could be formed. After immersion in acidic solution, impregnation with nickel and molybdenum were conducted to introduce active metal of nickel (Ni) and molybdenum (Mo) in the support structure. The catalyst formed, Ni-Mo/SiO2 was applied to convert crude palm oil into biofuels. The other silica catalyst was obtained from geothermal sludge. After washing, the catalyst was soaked in sulphuric acid solution to form acidic silica solid catalyst. The catalyst was applied in hydrolysis of seaweed-industry solid waste to produce glucose. The catalyst was relatively successful to facilitate 19-20% glucose yield, or up to 21% glucose selectivity from waste material.

scholarly journals Copper(I)-Catalyzed Click Chemistry as a Tool for the Functionalization of Nanomaterials and the Preparation of Electrochemical (Bio)Sensors

Sensors ◽  
2019 ◽  
Vol 19 (10) ◽  
pp. 2379 ◽  
Author(s):  
P. Yáñez-Sedeño ◽  
A. González-Cortés ◽  
S. Campuzano ◽  
J. M. Pingarrón
Keyword(s):  
Electrochemical Sensors ◽  
Functional Integration ◽  
Future Directions ◽  
Physiological Conditions ◽  
Electrode Surfaces ◽  
Wide Range ◽  
High Yields ◽  
By Products ◽  
Powerful Strategy

Proper functionalization of electrode surfaces and/or nanomaterials plays a crucial role in the preparation of electrochemical (bio)sensors and their resulting performance. In this context, copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC) has been demonstrated to be a powerful strategy due to the high yields achieved, absence of by-products and moderate conditions required both in aqueous medium and under physiological conditions. This particular chemistry offers great potential to functionalize a wide variety of electrode surfaces, nanomaterials, metallophthalocyanines (MPcs) and polymers, thus providing electrochemical platforms with improved electrocatalytic ability and allowing the stable, reproducible and functional integration of a wide range of nanomaterials and/or different biomolecules (enzymes, antibodies, nucleic acids and peptides). Considering the rapid progress in the field, and the potential of this technology, this review paper outlines the unique features imparted by this particular reaction in the development of electrochemical sensors through the discussion of representative examples of the methods mainly reported over the last five years. Special attention has been paid to electrochemical (bio)sensors prepared using nanomaterials and applied to the determination of relevant analytes at different molecular levels. Current challenges and future directions in this field are also briefly pointed out.

scholarly journals Influence of Initial Alkalinity of Lignocellulosic Waste on Their Enzymatic Degradation

2014 ◽  
Vol 40 (2) ◽  
pp. 103-113
Author(s):  
Marcin Wołczyński ◽  
Marta Janosz-Rajczyk
Keyword(s):  
Enzymatic Hydrolysis ◽  
Enzymatic Degradation ◽  
Suspended Solids ◽  
Lignocellulosic Waste ◽  
Initial Exposure ◽  
Total Sugars ◽  
Physical Chemical ◽  
Effect Of Treatment ◽  
Hydrolysis Of ◽  
By Products

Abstract The presented results of research on the effectiveness of enzymatic hydrolysis of lignocellulosic waste, depending on their initial depolymerisation in alkaline medium were considered in the context of the possibility of their further use in the fermentation media focused on the recovery of energy in the form of molecular hydrogen. The aim of this study was to determine the appropriate dose and concentration of a chemical reagent, whose efficiency would be high enough to cause decomposition of the complex, but without an excessive production of by-products which could adversely affect the progress and effectiveness of the enzymatic hydrolysis and fermentation. The effect of treatment on physical-chemical changes of homogenates’ properties such as pH, COD, the concentration of monosaccharide and total sugars and the concentration of total suspended solids and volatile suspended solids was determined. The enzymatic decomposition of lignocellulosic complex was repeatedly more efficient if the sample homogenates were subjected to an initial exposure to NaOH. The degree of conversion of complex sugars into simple sugars during enzymatic hydrolysis of homogenates pre-alkalized to pH 11.5 and 12.0 was 83.3 and 84.2% respectively, which should be sufficient for efficient hydrogen fermentation process.

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