scholarly journals Synthesis of five- and six-membered cyclic organic peroxides: Key transformations into peroxide ring-retaining products

2014 ◽  
Vol 10 ◽  
pp. 34-114 ◽  
Author(s):  
Alexander O Terent'ev ◽  
Dmitry A Borisov ◽  
Vera A Vil’ ◽  
Valery M Dembitsky
Keyword(s):  
Antitumor Agents ◽  
Scale Up ◽  
Molecular Structures ◽  
Organic Reactions ◽  
Present Review ◽  
Current Status ◽  
Organic Peroxides ◽  
Wide Range ◽  
Cyclic Compounds

The present review describes the current status of synthetic five and six-membered cyclic peroxides such as 1,2-dioxolanes, 1,2,4-trioxolanes (ozonides), 1,2-dioxanes, 1,2-dioxenes, 1,2,4-trioxanes, and 1,2,4,5-tetraoxanes. The literature from 2000 onwards is surveyed to provide an update on synthesis of cyclic peroxides. The indicated period of time is, on the whole, characterized by the development of new efficient and scale-up methods for the preparation of these cyclic compounds. It was shown that cyclic peroxides remain unchanged throughout the course of a wide range of fundamental organic reactions. Due to these properties, the molecular structures can be greatly modified to give peroxide ring-retaining products. The chemistry of cyclic peroxides has attracted considerable attention, because these compounds are used in medicine for the design of antimalarial, antihelminthic, and antitumor agents.

scholarly journals E-commerce and Digital Connectivity: Unleashing the Potential for Greater India–ASEAN Integration

2020 ◽  
Vol 2 (1) ◽  
pp. 62-81 ◽  
Author(s):  
Shouvik Kishore Majumdar ◽  
Angana Parashar Sarma ◽  
Srishti Majumdar
Keyword(s):  
Small And Medium Enterprises ◽  
Scale Up ◽  
Current Status ◽  
Policy Regimes ◽  
Partnership For Peace ◽  
Use Of Technology ◽  
Marginalised Groups ◽  
Wide Range ◽  
Cross Country ◽  
Medium Enterprises

Digital connectivity and e-commerce are emerging as important drivers to connect small and medium enterprises (SMEs) in developing countries to their domestic and global markets. India and the Association of Southeast Asian Nations (ASEAN) have emerged as fastest growing e-commerce and digital markets. Studies show that digital connectivity and e-commerce will help SMEs and marginalised groups in the two economies to diversify their client base at lower costs, while consumers will have access to a wide range of products. To support digitalisation and e-commerce, several initiatives have been taken by the governments in India and ASEAN. Many of them are related to enhancing cross-country trade and collaboration. The ASEAN–India Partnership for Peace, Progress and Shared Prosperity 2016–2020 is one such initiative. However, SMEs so far have not gained much from such initiatives. This article provides an overview of the current status of digtalisation and e-commerce in India and ASEAN. It examines their comparative positions in terms of technology adaptation and policy regimes and then presents the participation of these countries in bilateral, plurilateral and multilateral agreements and forums. Apart from infrastructure issues, restrictive regulations like data localisation requirements and lack of standards along with the defensive position of countries in international forums is adversely impacting the ability of their SMEs to scale up. The article provides recommendations on use of technology to help SMEs to scale up through a joint innovative knowledge sharing and e-commerce platform.

Factors Affecting Molecular Self-Assembly and Its Mechanism

2012 ◽  
Vol 9 (1) ◽  
pp. 43 ◽  
Author(s):  
Hueyling Tan
Keyword(s):  
Self Assembly ◽  
Building Blocks ◽  
Molecular Engineering ◽  
Molecular Structures ◽  
Polymer Science ◽  
New Approach ◽  
Factors Affecting ◽  
Dna Structures ◽  
Self Assembling ◽  
Wide Range

Molecular self-assembly is ubiquitous in nature and has emerged as a new approach to produce new materials in chemistry, engineering, nanotechnology, polymer science and materials. Molecular self-assembly has been attracting increasing interest from the scientific community in recent years due to its importance in understanding biology and a variety of diseases at the molecular level. In the last few years, considerable advances have been made in the use ofpeptides as building blocks to produce biological materials for wide range of applications, including fabricating novel supra-molecular structures and scaffolding for tissue repair. The study ofbiological self-assembly systems represents a significant advancement in molecular engineering and is a rapidly growing scientific and engineering field that crosses the boundaries ofexisting disciplines. Many self-assembling systems are rangefrom bi- andtri-block copolymers to DNA structures as well as simple and complex proteins andpeptides. The ultimate goal is to harness molecular self-assembly such that design andcontrol ofbottom-up processes is achieved thereby enabling exploitation of structures developed at the meso- and macro-scopic scale for the purposes oflife and non-life science applications. Such aspirations can be achievedthrough understanding thefundamental principles behind the selforganisation and self-synthesis processes exhibited by biological systems.

A Brief Review on the Development of Novel Potentially Active Azetidin-2-ones Against Cancer

2020 ◽  
Vol 24 (5) ◽  
pp. 473-486 ◽  
Author(s):  
Ligia S. da Silveira Pinto ◽  
Thatyana R. Alves Vasconcelos ◽  
Claudia Regina B. Gomes ◽  
Marcus Vinícius N. de Souza
Keyword(s):  
Side Effects ◽  
Anticancer Agents ◽  
Heterocyclic Compounds ◽  
Biological Activities ◽  
Present Review ◽  
Pharmacological Properties ◽  
Important Group ◽  
Wide Range ◽  
Anti Inflammatory

Azetidin-2-ones (β-lactams) and its derivatives are an important group of heterocyclic compounds that exhibit a wide range of pharmacological properties such as antibacterial, anticancer, anti-diabetic, anti-inflammatory and anticonvulsant. Efforts have been made over the years to develop novel congeners with superior biological activities and minimal potential for undesirable side effects. The present review aimed to highlight some recent discoveries (2013-2019) on the development of novel azetidin-2-one-based compounds as potential anticancer agents.

Current Status and Future Perspective for Research on Medicinal Plants with Anticancerous Activity and Minimum Cytotoxic Value

2019 ◽  
Vol 20 (12) ◽  
pp. 1227-1243
Author(s):  
Hina Qamar ◽  
Sumbul Rehman ◽  
D.K. Chauhan
Keyword(s):  
Side Effects ◽  
Medicinal Plants ◽  
Anticancer Agents ◽  
Drug Targets ◽  
Psidium Guajava ◽  
Current Status ◽  
Future Perspective ◽  
Wide Range

Cancer is the second leading cause of morbidity and mortality worldwide. Although chemotherapy and radiotherapy enhance the survival rate of cancerous patients but they have several acute toxic effects. Therefore, there is a need to search for new anticancer agents having better efficacy and lesser side effects. In this regard, herbal treatment is found to be a safe method for treating and preventing cancer. Here, an attempt has been made to screen some less explored medicinal plants like Ammania baccifera, Asclepias curassavica, Azadarichta indica, Butea monosperma, Croton tiglium, Hedera nepalensis, Jatropha curcas, Momordica charantia, Moringa oleifera, Psidium guajava, etc. having potent anticancer activity with minimum cytotoxic value (IC50 >3μM) and lesser or negligible toxicity. They are rich in active phytochemicals with a wide range of drug targets. In this study, these medicinal plants were evaluated for dose-dependent cytotoxicological studies via in vitro MTT assay and in vivo tumor models along with some more plants which are reported to have IC50 value in the range of 0.019-0.528 mg/ml. The findings indicate that these plants inhibit tumor growth by their antiproliferative, pro-apoptotic, anti-metastatic and anti-angiogenic molecular targets. They are widely used because of their easy availability, affordable price and having no or sometimes minimal side effects. This review provides a baseline for the discovery of anticancer drugs from medicinal plants having minimum cytotoxic value with minimal side effects and establishment of their analogues for the welfare of mankind.

Enzymes as a Reservoir of Host Defence Peptides

2020 ◽  
Vol 20 (14) ◽  
pp. 1310-1323
Author(s):  
Andrea Bosso ◽  
Antimo Di Maro ◽  
Valeria Cafaro ◽  
Alberto Di Donato ◽  
Eugenio Notomista ◽  
...  
Keyword(s):  
Innate Immunity ◽  
Biological Activity ◽  
Internal Structure ◽  
Catalytic Properties ◽  
Cellular Responses ◽  
Host Defence ◽  
Present Review ◽  
Active Peptides ◽  
Wide Range

Host defence peptides (HDPs) are powerful modulators of cellular responses to various types of insults caused by pathogen agents. To date, a wide range of HDPs, from species of different kingdoms including bacteria, plant and animal with extreme diversity in structure and biological activity, have been described. Apart from a limited number of peptides ribosomally synthesized, a large number of promising and multifunctional HDPs have been identified within protein precursors, with properties not necessarily related to innate immunity, consolidating the fascinating hypothesis that proteins have a second or even multiple biological mission in the form of one or more bio-active peptides. Among these precursors, enzymes constitute certainly an interesting group, because most of them are mainly globular and characterized by a fine specific internal structure closely related to their catalytic properties and also because they are yet little considered as potential HDP releasing proteins. In this regard, the main aim of the present review is to describe a panel of HDPs, identified in all canonical classes of enzymes, and to provide a detailed description on hydrolases and their corresponding HDPs, as there seems to exist a striking link between these structurally sophisticated catalysts and their high content in cationic and amphipathic cryptic peptides.

scholarly journals Current status of vascular access in Japan—from Dialysis Access Symposium 2017

2019 ◽  
Vol 20 (1_suppl) ◽  
pp. 38-44
Author(s):  
Mizuya Fukasawa
Keyword(s):  
Vascular Access ◽  
Current Status ◽  
Good Survival ◽  
Chronic Glomerulonephritis ◽  
Dialysis Access ◽  
Dialysis Patients ◽  
Survival Prognosis ◽  
Access Methods ◽  
Number Of Patients ◽  
Wide Range

At the second Dialysis Access Symposium held in Nagoya, Japan, a proposal was made to investigate the differences in vascular access methods used in different countries. In this article, we describe the management of vascular access in Japan. The Japanese population is rapidly aging, and the proportion of elderly patients on dialysis is also increasing. There were 325,000 dialysis patients in Japan at the end of 2015, of whom 65.1% were aged 65 years or above. The number of patients with diabetic nephropathy or nephrosclerosis as the underlying condition is also increasing, whereas the number with chronic glomerulonephritis is steadily decreasing. The Japanese health insurance system enables patients to undergo medical treatment at almost no out-of-pocket cost. Percutaneous transluminal angioplasty suffers from a severe device lag compared with other countries, but although there are limitations on permitted devices, the use of those that have been authorized is covered by medical insurance. One important point that is unique to Japan is that vascular access is performed and managed by doctors involved in dialysis across a wide range of disciplines, including nephrologists, surgeons, and urologists. This may be one factor contributing to the good survival prognosis of Japanese dialysis patients.

Accurate prediction of 195Pt NMR chemical shifts for a series of Pt(ii) and Pt(iv) antitumor agents by a non-relativistic DFT computational protocol

2014 ◽  
Vol 43 (14) ◽  
pp. 5409-5426 ◽  
Author(s):  
Athanassios C. Tsipis ◽  
Ioannis N. Karapetsas
Keyword(s):  
Dft Calculations ◽  
Anticancer Agents ◽  
Antitumor Agents ◽  
Chemical Shifts ◽  
Accurate Prediction ◽  
Nmr Chemical Shifts ◽  
Relativistic Dft ◽  
Square Planar ◽  
Wide Range ◽  
Computational Protocol

Exhaustive benchmark DFT calculations reveal that the non-relativistic GIAO-PBE0/SARC-ZORA(Pt)∪6-31+G(d)(E) computational protocol predicts accurate 195Pt NMR chemical shifts for a wide range of square planar Pt(ii) and octahedral Pt(iv) anticancer agents.

scholarly journals MOCVD Grown HgCdTe Heterostructures for Medium Wave Infrared Detectors

Coatings ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 611
Author(s):  
Waldemar Gawron ◽  
Jan Sobieski ◽  
Tetiana Manyk ◽  
Małgorzata Kopytko ◽  
Paweł Madejczyk ◽  
...  
Keyword(s):  
Buffer Layer ◽  
Infrared Detectors ◽  
Lattice Mismatch ◽  
Layer Growth ◽  
Ex Situ ◽  
Current Status ◽  
Organic Chemical ◽  
Infrared Band ◽  
Donor And Acceptor ◽  
Wide Range

This paper presents the current status of medium-wave infrared (MWIR) detectors at the Military University of Technology’s Institute of Applied Physics and VIGO System S.A. The metal–organic chemical vapor deposition (MOCVD) technique is a very convenient tool for the deposition of HgCdTe epilayers, with a wide range of compositions, used for uncooled infrared detectors. Good compositional and thickness uniformity was achieved on epilayers grown on 2-in-diameter, low-cost (100) GaAs wafers. Most growth was performed on substrates, which were misoriented from (100) by between 2° and 4° in order to minimize growth defects. The large lattice mismatch between GaAs and HgCdTe required the usage of a CdTe buffer layer. The CdTe (111) B buffer layer growth was enforced by suitable nucleation procedure, based on (100) GaAs substrate annealing in a Te-rich atmosphere prior to the buffer deposition. Secondary-ion mass spectrometry (SIMS) showed that ethyl iodide (EI) and tris(dimethylamino)arsenic (TDMAAs) were stable donor and acceptor dopants, respectively. Fully doped (111) HgCdTe heterostructures were grown in order to investigate the devices’ performance in the 3–5 µm infrared band. The uniqueness of the presented technology manifests in a lack of the necessity of time-consuming and troublesome ex situ annealing.

Synthesis of sp3-Enriched β-Fluoro Sulfonyl Chlorides

Synthesis ◽  
2020 ◽  
Author(s):  
Oleksandr O. Grygorenko ◽  
Rustam Gurbanov ◽  
Andriy Sokolov ◽  
Sergey Golovach ◽  
Kostiantyn Melnykov ◽  
...  
Keyword(s):  
Drug Discovery ◽  
Double Bond ◽  
Building Blocks ◽  
Protecting Groups ◽  
Sulfonyl Chlorides ◽  
Wide Range ◽  
Cyclic Compounds

AbstractA three-step approach to the synthesis of sp3-enriched β-fluoro sulfonyl chlorides starting from alkenes is reported. The method was successfully applied to a wide range of acyclic and cyclic substrates, bearing either an exocyclic or an endocyclic double bond. The procedure worked with a wide range of substrates and tolerated a number of functional and protecting groups. Moreover, the target cyclic compounds were obtained as single cis diastereomers on a multigram scale. The title compounds are promising building blocks for drug discovery that can be used to obtain sp3-enriched β-fluoro and α,β-unsaturated sulfonamides.

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