für 53.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Transition metals (Pd, Ni, Cu, Fe, Au) have played significant role in organic chemistry for creating organic molecules. One metal palladium with different ligands is being used as efficient catalyst for C-C bond formation. Palladium catalyzed reactions are used in the synthesis of many natural products, pharmaceutical drugs and advance materials. In this research work, Heck, Suzuki and Sonogashira reactions of di and tri halogenated and dihydroxy heterocycles (benzothiophene, pyrazine, quinoxaline, pyrimidine, furan and flavone) with photophysical properties of some alkynylated products of Pyrimidines and furans, have been studied in detail. ····· 10361146376
für 26.90€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Carl Wilhelm Scheele (1742 - 1786) war ein deutsch-schwedischer Apotheker und Chemiker, der zeitlebens nach chemischen Verbindungen suchte. Mit seinen Studien und Experimenten gelang es ihm unter anderem, einen wichtigen Beitrag zur Entdeckung des Sauerstoffs und Stickstoffs zu leisten. Dokumentiert hat Scheel diese Ergebnisse in dem hier vorliegenden Buch, das von dem Chemiker und Nobelpreisträger Wilhelm Ostwald veröffentlicht wurde. Sorgfältig bearbeiteter Nachdruck der Originalausgabe von 1894. ····· 10361139492
für 41.90€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Mit Die Diastasen und ihre Rolle in der Praxis trägt der Enzymologe Jean Effront dem immer größer werdendem wissenschaftlichen Interesse seiner Zeit an der chemischen Fermentation Rechnung. Effront, der als erster den Standardprozess, der zum Beschleunigen der Fermentation von Bier genutzt wird, aufgezeigt hat, legt eine ganzheitliche Darstellung der Enzyme der Kohlenhydrate sowie der Oxydasen vor. Seine Zielgruppe sind sowohl alle wissenschaftlichen Interessierten als auch praktisch Interessierte, beispielsweise aus der Gährungsindustrie.Sorgfältig bearbeiteter Nachdruck der Originalausgabe von 1900. ····· 10361139347
für 28.90€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray In Anleitung zur Darstellung organischer Präparate hat der Chemiker Emil Fischer eine Fülle verschiedener Versuchsaufbauten zusammengetragen. Detailliert beschreibt er Auswahl und Anordnung der Präparate, wobei Leichtigkeit, Schnelligkeit sowie nicht zuletzt Gefahrlosigkeit der Experimente angemessen berücksichtigt wird. Fischers Werk ist ein nützlicher Leitfaden für Lehrende und Studierende.Sorgfältig bearbeiteter Nachdruck der Originalausgabe von 1893. ····· 10361139261
für 33.90€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray In dem hier vorliegenden Werk veröffentlicht der deutsche Mineraloge Heinrich Adolf Baumhauer (1848 1926) eine Auswertung von ihm durchgeführten Ätzfiguren an Kristallen. In seinen Ergebnissen gibt er eine Übersicht über die wichtigsten Resultate der Anwendung der Ätzmethode. Ergänzt werden diese durch die Darlegung einer Reihe von speziellen Ätzerscheinungen an 12 verschiedenen kristallischen Stoffen.Sorgfältig bearbeiteter Nachdruck der Originalausgabe von 1894. ····· 10361139121
für 35.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Una investigación centrada en la síntesis y evaluación farmacológica de derivados N-alquilados de (±)-4-metiltioanfetamina, ((±)-MTA), un liberador selectivo de serotonina no neurotóxico e inhibidor selectivo reversible de MAO-A. Además se resolvieron los enantiómeros de (±)-MTA. Se sintetizaron moléculas con distintos largos de cadena N-alquílica. Todos los compuestos obtenidos fueron evaluados en cuanto a su capacidad como inhibidores de MAO-A, resultando ser todos los derivados racémicos menos potentes que MTA. (+)-MTA es la molécula más activa de las evaluadas y dos veces mas potente que el compuesto racémico, (-)-MTA es 20 veces menos activa que la mezcla racémica. La inhibición de MAO-A es reversible en todos los casos. En cuanto a la inhibición de MAO-B, ninguna de las drogas evaluadas fue activa, excepto NAMTA y esto no cambió por preincubación, lo que indica que la falta de inhibición de MAO-B es independiente del tiempo. Los derivados monoalquilados fueron evaluados en sus propiedades neurotóxicas sobre células de cultivo. Presentaron baja toxicidad comparables con aquellos que presenta l-deprenil, usada actualmente en el tratamiento de la enfemedad de Parkinson. ····· 10361137025
für 44.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray The stereochemistry control of radical reactions has been a field of intense investigations in the last 20 years. Rules have been proposed to rationalize the results, interestingly these rules parallels the ones formerly developed for ionic and concerted reactions. The use of captodative radicals combined with phenylseleno group transfer reaction is a powerful tool which allows a wide range of chain reaction in intra and inter molecular manner. In this book we will present several aspects of these type of radical generated form selenylated alpha hydroxy acids derivatives. These reaction have been studied using different substrates. A new method of obtaining optically pure dioxalones is also presented. These reactions might be very useful during delicate steps of total synthesis of natural products. Organic chemists could find very useful some of the application that are represented in this book especially the good stereoselectivity control that these reaction have. ····· 10361135704
für 61.20€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Homoallylic alcohols and amines are fundamental building blocks for many biologically active compounds. The allylation of carbonyl compounds with allyl organometallic reagents constitutes a simple and straight forward approach for their synthesis. Allyl indium reagents have emerged as a reagent of choice for allylation of carbonyl compounds under both aqueous and non-aqueous conditions. However, in application of this approach for the synthesis of homoallylic alcohols/ amines from ketones/ imines, the lower electrophilicity of ketone/imine carbon makes the transfer of allyl group to ketone/imine carbon much more challenging. The ease of hydrolysis of imine to carbonyl compound and amine further add to the difficulties. The present work is aimed to unravel the regio- and diastereochemical aspects in indium mediated allylation of ketones bearing proton donor groups (OH, COOH) alpha to carbonyl moiety and imines derived from heterocycles like pyridine-2-imines, quinoline-2-imines and indole-3-imines. In selected cases the homoallylic alcohols have been subjected to iodine mediated cyclization to provide 2,3-diaryltetrahydrofuran and 3-hydroxy-3,4-dihydrofuran-2(5H)-one derivatives. ····· 10361135682
für 44.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Over the last few years, a wide range of biologically active carbazole alkaloids have been isolated from plant sources. Many of these natural products manifest a variety of biological activities. In addition to their use in medicinal chemistry, carbazoles have attracted increasing attention from the community of material scientists owing to their potential in photophysical and optoelectronic applications. Polyvinylcarbazole (PVK) has been extensively investigated for its use in photorefractive materials and xerography, while N-ethylcarbazole (ECz) was recognized as an effective charge-transporting functional plasticizer for PVK and other doped polymers. In view of these important applications, we set out to develop an anionic cycloaddition for the carbazole synthesis and to apply the method to the synthesis of naturally occurring carbazoles. The dissertation results should be useful to researchers and especially to students and professionals in organic chemistry, material chemistry or medicinal chemistry fields. ····· 10361135653
für 53.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Organic Chemistry: Structure, Mechanism, and Reactivity logically presents in simple and clear terms the required facts and principles needed to succeed in Organic Chemistry Examinations. The organic book contains Thirteen Chapters that were clearly written, better illustrated and presented in Three Sections: Part I Structure (Nomenclature and Atomic Structure & Bonding) Part II Mechanism (Organic Reactions & Reaction Mechanisms) and Part III- Reactivity (Organic Terms, Hydrocarbons, Alcohols, Carboxylic acids, Carbohydrates, Lipids & Esters, Aromatic Compounds, Aliphatic Nitrogen compounds and Aldehydes & Ketones). Each chapter of the book reflects basic sophistications of a well-tutored and experienced writer and these qualities of presentation will certainly stimulates interests in learners. Sufficient for candidates preparing for General Certificate of Education, Polytechnic, University and other relevant examinations. This book, therefore is an additional material that would be highly useful for both students and teachers of Organic Chemistry Keywords: Organic Chemistry, Structure, Mechanism, Reactivity, Curved Arrow, Reaction ····· 10361135553
für 61.20€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray This book is divided into two sections sections A and B. Section A describes the isolation and structure elucidation of seven known compounds [1-7] i.e. stigmasterol (1), -sitosterol (2), -sitosterol glucoside (3), oleanolic acid (4), harmine (5), 7,3`,4`-trimethoxyflavone (6), and 5-methylflavanone (7). Compounds [5-7] were for the first time reported from this plant. Section B describes the synthesis of 2, 4, 6-trichlorophenylhydrazones and 6-nitrobenzimidazole derivatives. These synthesized compounds were also biological screened for their glycation of protein, -chymotrypsin, carbonic anhydrase, urease, antioxidant (DPPH and superoxide anion scavenging assays) and phosphodiesterase activities. Interestingly, most of these synthesized compounds showed excellent medicinal activities. ····· 10361134593
für 53.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray As a source of medicines, plants have formed the basis for sophisticated traditional systems and continue providing mankind with new remedies. About twenty five percentage of all medical prescriptions are based on substances derived from plants or plant-derived synthetic analogues. To avoid hazards associated with the wrong use of medicinal herbs, isolation and structure-elucidation, as well as the physiological activity assessment represent the scientific basis to safe medicaments. This book contains some methods of extraction, fractionation, separation and purification of natural products from a plant species, as well as structure elucidation by spectral tools. This book, therefore, provides young researchers in the field of Natural Products` Chemistry, who are willing to build up their competencies, with some practical techniques in extraction, separation, purification, spectral analysis, and structure-elucidation of natural products. This book describes working in low or moderately sophisticated lab equipment and facilities, which is a good start for beginners and for researchers in poor countries. ····· 10361134417
für 53.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Several reactions taught in Pharmaceutical and medicinal chemistry laboratory today are hazardous to environment and hence needs to be modified. With an impetus from Pollution control act, Green Chemistry a relatively newer branch has originated. This book discusses the concepts and the implementation of various green chemical reactions. Basic concepts of ionic liquids, organic synthesis and their applications for name organic reactions are discussed. In organic synthesis, ionic liquids have been extensively used for the variety of synthetic transformations. Ionic liquids have been emerging as a versatile class of green solvents with many projected advantages compared with conventional media. In the present book, we would account the synthesis of various kinds of nitrogen heterocycles using variety of ionic liquids too. ····· 10361134264
für 53.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray There are over 750,000 plants on earth relatively only a few of these have been studied scientifically. Modern pharmacology looks for one active ingredient and seeks to isolate it to the exclusion of all the others. Most research on plants continues to focus on identifying and isolating active ingredients rather than studying the medicinal properties of the whole plant. The isolation, purification and identification of active ingredients of one of such medicinal plants that was studied is Ficus platyphylla (Moraceae). Phytochemical analysis of Ficus platyphylla was uniquely designed to give professionals on natural products studies and students an overview of the phytochemical compounds, accepted analytical methods for the isolation of pure compounds and the spectroscopic techniques required for their identification. The research protocols adopted in an impecunious system leading to the isolation of a compound for the first time from the bark of Ficus platyphylla is discussed. ····· 10361134181
für 44.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray The utility of nitrones in synthetic organic chemistry has been widely illustrated. The nitrone moiety can be regarded as a 3 centered dipolar 4 system, which enables 1,3-dipolar cycloaddition reactions with different dipolarophilic reagent to occur. 1,3-dipolar cycloaddition reaction between a nitrone and an olefinic dipolarophiles is an efficient method for the synthesis of isoxazolidine and isoxazoline ring systems. Nitrones are also versatile intermediates for the synthesis of natural products and many biologically interesting molecules. Owing to the labile nature of the N O bond under mild reducing conditions, isoxazolidines provide easy access to a variety of fascinating 1,3-difunctional amino alcohols. To run a chemical reaction under an environment friendly condition is a challenge now-adays. The development of environmentally benign chemical processes (aqueous phase synthesis, microwave induced reactions and ionic liquids as solvent) have received much attention in recent years. ····· 10361133602
für 53.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray It has been nearly fifty years since the advent of solid phase method for the assembly of peptides. One of the main difficulties facing researchers in this field is that of obtaining quantities of peptides and proteins in a pure state. Isolation of proteins form natural resources can be laborious and often provides only tiny quantities. Investigations dealing with the quantitative aspects of polymer-supported reactions have shown that the insoluble support does have a significant dynamic influence on the bound substrates. An efficient polymeric support for peptdide synthesis should have optimum hydrophobic-hydrophilic balance compatible with the peptide being synthesized. This book illustrates the synthesis and characterization of a novel polymer support, polystyrene crosslinked with 1,6-hexanediol diacrylate for the successful synthesis of peptides. The compatibility of the new support is proved by synthesizing sequences of Thioredoxin, which is otherwise difficult to synthesize. Thioredoxin is a naturally occurring sulphur reducing protein containing 108 amino acids. The book is useful to researchers, scientists and academia in studying the intricacies of solid phase synthesis. ····· 10361133572
für 49.41€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Steroids play important roles in the human body, including, but not limited to: controlling meiosis, fat storage, protein and carbohydrate metabolism, muscle growth, immune function and nerve cell membrane chemistry. Almost one-third of all currently prescribed medications contain steroid skeleton e.g. Proellex, Chronocort, Corticosteroids etc. Many medicinally important steroid derivatives do not occur in nature and must be synthesized in the laboratory. The modification of steroid skeleton or fusion of any heterocyclic ring system such as triazolidinones, oxathiolanes, and carbohydrate group, to steroid was found to augment the biological and industrial revolution as it results in change of electronic and molecular properties and have shown marked biological activities like anti-cancer, antimicrobial, antimalarial and anti-HIV. Thus, innumerable methods are necessary to develop across to find the better analogues of steroid natural products to show the potent biological activities. The purpose of the present book is to incorporate advances in the area of organic synthesis. ····· 10361132885
für 53.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Plants and their secondary metabolites are the rich source of drugs against several diseases. Therefore, our aim of study was to isolate and characterized several secondary metabolites from Lawsonia alba (Henna) using state of the art spectroscopic techniques e.g., UV, IR, Mass spectroscopy, 1H- and 13C-NMR spectroscopy and explore the bioactivities of crude plant extract, semipure frcations and pure constituents. ····· 10361131938
für 71.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray This book describes the development of `smart` biomaterials based on the naturally derived poly-[(R)-3-hydroxybutyrate](PHB). The first part of this book focuses on biodegradable multiblock thermoresponsive poly(ether ester urethane)s consisting of poly(ethylene glycol) (PEG), poly(propylene glycol) (PPG) and PHB. The physical properties as well as applicative studies of these gels such as drug release and tissue engineering are presented. In the second part, the preparation of novel thermoresponsive micelles is presented. Using this copolymer, a thermoresponsive substrate was fabricated by drop-coating with an aqueous polymer solution, and used for the attachment and nonenzymatic temperature-induced detachment of human mesenchymal stem cells and mouse embryonic stem (ES) cells. The promising results from the studies show that these copolymers could be utilized as surface modifiers for tissue engineering applications. In summary, the synthesis of novel smart biomaterials and their application in the fields of drug delivery and tissue engineering are described in this book. ····· 10361119523
für 44.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Thin-film organic semiconductor devices such as organic light emitting diodes (OLEDs) and organic photovoltaics can be fabricated in a variety of ways, including physical vapor deposition (PVD). PVD is a process for depositing thin films of precisely controlled thicknesses and material compositions onto a substrate in a vacuum system. Resistively heated crucibles, referred to as boats, are commonly used to heat source materials to a sufficient temperature to cause vaporization or sublimation. These boat designs typically contain a single opening which results in a conical vapor stream for coating both a substrate and a nearby thickness and rate sensor. In this study, a new boat design incorporating a dual vapor stream, where one vapor stream is pointed toward the sensor and the other is directed toward the substrate in an orthogonal orientation, were investigated. This design is intended to provide particularly useful features for the fabrication of organic thin-films of complex compositions involving multiple components. It is also designed to reduce material waste by shortening the source to substrate distance. ····· 10361119444
für 44.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray This study involved a survey on the use of dithiocarbamates in agriculture practices in Bukavu Region and the determination of their residues in vegetables (tomatoes and cabbages) from five main sites supplying Bukavu town with vegetables. Analytical method based on HPLC-UV, developed by Codex Committee on pesticide residues was employed for the analysis of mancozeb residues from vegetables samples (tomatoes and cabbages) collected from Bukavu region in DRC. The laboratory analysis showed a Limit of Detection of 0.01 mg/kg, the recoveries ranged from 73.5 to 82.1 % for cabbages and 64.0 to 66.9 % for tomatoes. The concentration of the residues expressed as mancozeb (the factor conversion for mancozeb derivative = 1.13) in tomatoes varied (in mg/ kg) from no detectable values (ND) to 1.33 for Kamanyola, ND to 1.87 for Nyangezi, 1.44 to 3.99 for Katana, 1.54 to 4.06 for Miti and ND to 4.65 for Mudaka samples. The average values ± SD (Standard Deviation) in mg/ kg for the five study sites were 0.89 ± 0.35, 1.31 ± 0.44, 2.48 ± 1.02, 2.71 ± 0.82 and 3.25 ± 1.25 respectively. ····· 10361119320
für 44.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray The rapid progress in the field of organic conducting materials has found possible applications for sensors and molecular electronics. Among them both conducting polymers and carbon nanotubes, specifically Single Walled Carbon Nanotubes and Multi Walled Carbon Nanotubes, are good candidates for these applications. Their associations can lead to the synthesis of materials called nanocomposites which resemble the whole physical and chemical properties of the starting ones. This book is therefore focused on the fabrication of nanocomposites materials, based on polyaniline derivatives and multi-walled carbon nanotubes, by means of standardized oxidative polymerization, and the subsequent characterizations by different techniques to asses the physical and chemical properties of the synthesised materials. ····· 10361119233· 1 ·· 2 ·· 3 ·· 4 ·· 5 ·· 6 ·· 7 ·· 8 ·· 9 ·
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