Iron-Promoted Construction of Indoles via Intramolecular Oxidative C–N Coupling of 2-Alkenylanilines Using Persulfate

Synthesis ◽  
2019 ◽  
Vol 51 (16) ◽  
pp. 3085-3090
Author(s):  
Menglan Wang ◽  
Yudong Li ◽  
Qing-An Wu ◽  
Shuping Luo ◽  
Yuehui Li
Keyword(s):  
Intramolecular Cyclization ◽  
Synthetic Route ◽  
Cyclization Reactions ◽  
Wide Range ◽  
First Time ◽  
Drug Intermediates

Indole scaffold synthesis relies primarily on oxidative C–H amination of N-protected alkenylanilines for C–N intramolecular cyclization reactions. Herein, for the first time, without N-protection, various readily prepared 2-alkenylanilines were transformed into the desired indole products in good yields by using K2S2O8 as oxidant in the presence of catalytic amounts of FeF2. The K2S2O8/FeF2 system offers a direct and benign synthetic route to 3-arylindoles and it is applicable to a wide range of substituted indoles including drug intermediates.

PIFA-Mediated Oxidative Cyclization Reactions of α-Acyl Acrylamides: A Synthetic Route to Substituted Isoxazol-3(2H)-ones

Synthesis ◽  
2018 ◽  
Vol 50 (09) ◽  
pp. 1875-1882 ◽  
Author(s):  
Rui Zhang ◽  
Dewen Dong ◽  
Jingwen Yuan ◽  
Chitturi Rao ◽  
Qian Zhang ◽  
...  
Keyword(s):  
Intramolecular Cyclization ◽  
Oxidative Cyclization ◽  
Metal Catalyst ◽  
Synthetic Route ◽  
Cyclization Reactions ◽  
Reaction Conditions ◽  
Catalyst Free ◽  
Free Oxidation

An intramolecular cyclization of various α-acyl β-amino acrylamides in the presence of PIFA and TFA is described. This transformation features mild reaction conditions, simple execution, high chemo­selectivity, and metal catalyst-free oxidation, and thereby, provides not only an alternative protocol for the construction of N–O bond, but also an efficient and straightforward synthesis of substituted isoxazol-3(2H)-ones from readily available α-acyl acrylamides.

scholarly journals Addition of Zn during the phosphine-based synthesis of indium phospide quantum dots: doping and surface passivation

2015 ◽  
Vol 6 ◽  
pp. 1237-1246 ◽  
Author(s):  
Natalia E Mordvinova ◽  
Alexander A Vinokurov ◽  
Oleg I Lebedev ◽  
Tatiana A Kuznetsova ◽  
Sergey G Dorofeev
Keyword(s):  
Quantum Dots ◽  
Surface Passivation ◽  
Particle Growth ◽  
Colloidal Quantum Dots ◽  
Synthetic Route ◽  
Zn Doping ◽  
Photochemical Etching ◽  
Wide Range ◽  
Dopant Atoms ◽  
First Time

Zinc-doped InP(Zn) colloidal quantum dots (QDs) with narrow size distribution and low defect concentration were grown for the first time via a novel phosphine synthetic route and over a wide range of Zn doping. We report the influence of Zn on the optical properties of the obtained quantum dots. We propose a mechanism for the introduction of Zn in the QDs and show that the incorporation of Zn atoms into the InP lattice leads to the formation of Zn acceptor levels and a luminescence tail in the red region of the spectra. Using photochemical etching with HF, we confirmed that the Zn dopant atoms are situated inside the InP nanoparticles. Moreover, doping with Zn is accompanied with the coverage of the QDs by a zinc shell. During the synthesis Zn myristate covers the QD nucleus and inhibits the particle growth. At the same time the zinc shell leads to an increase of the luminescence quantum yield through the reduction of phosphorous dangling bonds. A scenario for the growth of the colloidal InP(Zn) QDs was proposed and discussed.

Influence of Experimental Parameters on the Synthesis of Gold Nanoparticles by Electroless Deposition

2011 ◽  
Vol 324 ◽  
pp. 125-128
Author(s):  
Mikhael Bechelany ◽  
Jamil Elias ◽  
Jihane Hankache ◽  
Pierre Brodard ◽  
Laetitia Philippe ◽  
...  
Keyword(s):  
Gold Nanoparticles ◽  
Electroless Deposition ◽  
Au Nanoparticles ◽  
Synthetic Route ◽  
Galvanic Displacement ◽  
Synthetic Process ◽  
Wide Range ◽  
Experimental Parameters ◽  
First Time

We report a simple synthetic route based on electroless deposition (galvanic displacement) and natural lithography to synthesize organized Au nanoparticles (NPs). We will study the influence of different experimental parameters (time, temperature, pH and additives) on the synthetic process. We show for the first time the formation of organized extended domains of Au nanorings using gelatin as an additive. A wide range of applications can be envisaged for these nanostructures, as for instance chemical- and bio-sensors using the SERS effect.

Safety assessment of biological raw materials in the system of medicines quality assurance

2020 ◽  
pp. 63-72
Author(s):  
Yu. Olefir ◽  
E. Sakanyan ◽  
I. Osipova ◽  
V. Dobrynin ◽  
M. Smirnova ◽  
...  
Keyword(s):  
Raw Materials ◽  
State Level ◽  
The State ◽  
Spongiform Encephalopathy ◽  
Safety Standards ◽  
Wide Range ◽  
The Russian Federation ◽  
Key Aspects ◽  
First Time ◽  
Medicines Quality

The entry of a wide range of biotechnological products into the pharmaceutical market calls for rein-forcement of the quality, efficacy and safety standards at the state level. The following general monographs have been elaborated for the first time to be included into the State Pharmacopoeia of the Russian Federation, XIV edition: "Viral safety" and "Reduction of the risk of transmitting animal spongiform encephalopathy via medicinal products". These general monographs were elaborated taking into account the requirements of foreign pharmacopoeias and the WHO recommendations. The present paper summarises the key aspects of the monographs.

Innovation in Byzantine Medicine

2020 ◽  
Author(s):  
Petros Bouras-Vallianatos
Keyword(s):  
Human Physiology ◽  
Medical Literature ◽  
Cultural Exchange ◽  
Significant Degree ◽  
Medieval Medicine ◽  
Medieval Latin ◽  
Main Thesis ◽  
Wide Range ◽  
Comprehensive Examination ◽  
First Time

Byzantine medicine is still a little-known and misrepresented field not only in the wider arena of debates on medieval medicine but also among Byzantinists. Byzantine medical literature is often viewed as ‘stagnant’ and mainly preserving ancient ideas; and our knowledge of it continues to be based to a great extent on the comments of earlier authorities, which are often repeated uncritically. This book presents the first comprehensive examination of the medical corpus of, arguably, the most important late Byzantine physician John Zacharias Aktouarios (c.1275–c.1330). The main thesis is that John’s medical works show an astonishing degree of openness to knowledge from outside Byzantium combined with a significant degree of originality, in particular, in the fields of uroscopy, pharmacology, and human physiology. The analysis of John’s edited (On Urines and On Psychic Pneuma) and unedited (Medical Epitome) works is supported for the first time by the consultation of a large number of manuscripts. The study is also informed by evidence from a wide range of medical sources, including previously unpublished ones, and texts from other genres, such as epistolography and merchants’ accounts. The contextualization of John’s works sheds new light on the development of Byzantine medical thought and practice, and enhances our understanding of the late Byzantine social and intellectual landscape. Finally, John’s medical observations are also examined in the light of examples from the medieval Latin and Islamic worlds, placing his medical theories in the wider Mediterranean milieu and highlighting the cultural exchange between Byzantium and its neighbours.

Rebels, Believers, Survivors

2020 ◽  
Author(s):  
Noel Malcolm
Keyword(s):  
Catholic Church ◽  
Religious Conversion ◽  
Late Nineteenth Century ◽  
Napoleonic Wars ◽  
Conversion To Islam ◽  
Wide Range ◽  
History Of ◽  
External Powers ◽  
First Time ◽  
Modern Myth

This book of essays covers a wide range of topics in the history of Albania and Kosovo. Many of the essays illuminate connections between the Albanian lands and external powers and interests, whether political, military, diplomatic or religious. Such topics include the Habsburg invasion of Kosovo in 1689, the manoeuvrings of Britain and France towards the Albanian lands during the Napoleonic Wars, the British interest in those lands in the late nineteenth century, and the Balkan War of 1912. On the religious side, essays examine ‘crypto-Christianity’ in Kosovo during the Ottoman period, the stories of conversion to Islam revealed by Inquisition records, the first theological treatise written in Albanian (1685), and the work of the ‘Apostolic Delegate’ who reformed the Catholic Church in early twentieth-century Albania. Some essays bring to life ordinary individuals hitherto unknown to history: women hauled before the Inquisition, for example, or the author of the first Albanian autobiography. The longest essay, on Ali Pasha, tells for the first time the full story of the role he played in the international politics of the Napoleonic Wars. Some of these studies have been printed before (several in hard-to-find publications, and one only in Albanian), but the greater part of this book appears here for the first time. This is not only a contribution to Albanian and Balkan history it also engages with many broader issues, including religious conversion, methods of enslavement within the Ottoman Empire, and the nature of modern myth-making about national identity.

Recycling and Reuse in the Roman Economy

2020 ◽  
Keyword(s):  
Building Materials ◽  
Computational Modelling ◽  
Late Antique ◽  
Roman Economy ◽  
Wide Range ◽  
The Status ◽  
Recent Developments ◽  
Methodological Approaches ◽  
First Time ◽  
Site Types

The recycling and reuse of materials and objects were extensive in the past, but have rarely been embedded into models of the economy; even more rarely has any attempt been made to assess the scale of these practices. Recent developments, including the use of large datasets, computational modelling, and high-resolution analytical chemistry, are increasingly offering the means to reconstruct recycling and reuse, and even to approach the thorny matter of quantification. Growing scholarly interest in the topic has also led to an increasing recognition of these practices from those employing more traditional methodological approaches, which are sometimes coupled with innovative archaeological theory. Thanks to these efforts, it has been possible for the first time in this volume to draw together archaeological case studies on the recycling and reuse of a wide range of materials, from papyri and textiles, to amphorae, metals and glass, building materials and statuary. Recycling and reuse occur at a range of site types, and often in contexts which cross-cut material categories, or move from one object category to another. The volume focuses principally on the Roman Imperial and late antique world, over a broad geographical span ranging from Britain to North Africa and the East Mediterranean. Last, but not least, the volume is unique in focusing upon these activities as a part of the status quo, and not just as a response to crisis.

scholarly journals A Virtual Telescope for the Open University Science Foundation Course

1998 ◽  
Vol 162 ◽  
pp. 100-105
Author(s):  
Andrew J. Norton ◽  
Mark H. Jones
Keyword(s):  
Social Science ◽  
Open University ◽  
Distance Teaching ◽  
The Arts ◽  
Wide Range ◽  
University Science ◽  
First Time ◽  
Degree Level ◽  
Selection Of

The Open University is the UK's foremost distance teaching university. For over twenty five years we have been presenting courses to students spanning a wide range of degree level and vocational subjects. Since we have no pre-requisites for entry, a major component of our course profile is a selection of foundation courses comprising one each in the Arts, Social Science, Mathematics, Technology and Science faculties. The Science Faculty's foundation course is currently undergoing a substantial revision. The new course, entitled “S103: Discovering Science”, will be presented to students for the first time in 1998.

scholarly journals Autophagy Deficiency by Atg4B Loss Leads to Metabolomic Alterations in Mice

Metabolites ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 481
Author(s):  
Gemma G. Martínez-García ◽  
Raúl F. Pérez ◽  
Álvaro F. Fernández ◽  
Sylvere Durand ◽  
Guido Kroemer ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Amino Acids ◽  
Mammalian Cells ◽  
Tissue Homeostasis ◽  
In Vivo Studies ◽  
Protective Mechanism ◽  
Cardiac Damage ◽  
Wide Range ◽  
First Time

Autophagy is an essential protective mechanism that allows mammalian cells to cope with a variety of stressors and contributes to maintaining cellular and tissue homeostasis. Due to these crucial roles and also to the fact that autophagy malfunction has been described in a wide range of pathologies, an increasing number of in vivo studies involving animal models targeting autophagy genes have been developed. In mammals, total autophagy inactivation is lethal, and constitutive knockout models lacking effectors of this route are not viable, which has hindered so far the analysis of the consequences of a systemic autophagy decline. Here, we take advantage of atg4b−/− mice, an autophagy-deficient model with only partial disruption of the process, to assess the effects of systemic reduction of autophagy on the metabolome. We describe for the first time the metabolic footprint of systemic autophagy decline, showing that impaired autophagy results in highly tissue-dependent alterations that are more accentuated in the skeletal muscle and plasma. These changes, which include changes in the levels of amino-acids, lipids, or nucleosides, sometimes resemble those that are frequently described in conditions like aging, obesity, or cardiac damage. We also discuss different hypotheses on how impaired autophagy may affect the metabolism of several tissues in mammals.

scholarly journals Non-Nucleoside Agonists of the Adenosine Receptors: An Overview

2019 ◽  
Vol 12 (4) ◽  
pp. 150 ◽  
Author(s):  
Dal Ben ◽  
Lambertucci ◽  
Buccioni ◽  
Martí Navia ◽  
Marucci ◽  
...  
Keyword(s):  
Adenosine Receptors ◽  
Biological Activities ◽  
Great Majority ◽  
Synthetic Route ◽  
Wide Range ◽  
Pharmacological Interest ◽  
Molecular Modeling Studies ◽  
Synthetic Routes ◽  
Alternative Set ◽  
Structural Classes

Potent and selective adenosine receptor (AR) agonists are of pharmacological interest for the treatment of a wide range of diseases and conditions. Among these derivatives, nucleoside-based agonists represent the great majority of molecules developed and reported to date. However, the limited availability of compounds selective for a specific AR subtype (i.e., A2BAR) and a generally long and complex synthetic route for largely substituted nucleosides are the main drawbacks of this category of molecules. Non-nucleoside agonists represent an alternative set of compounds able to stimulate the AR function and based on simplified structures. This review provides an updated overview on the structural classes of non-nucleoside AR agonists and their biological activities, with emphasis on the main derivatives reported in the literature. A focus is also given to the synthetic routes employed to develop these derivatives and on molecular modeling studies simulating their interaction with ARs.

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