Some applications of deep eutectic solvents in alkylation of heterocyclic compounds: A review of the past 10 years

2021 ◽  
Vol 27 (1) ◽  
pp. 45-56
Author(s):  
Maja Molnar ◽  
Melita Lončarić ◽  
Martina Jakovljević ◽  
Mario Komar ◽  
Mirjana Lončar

AbstractThis mini-review encapsulates the latest findings (past 10 years) in the field of the deep eutectic solvents (DESs) application in the alkylation/arylation of different heterocyclic compounds. These solvents have been developed to fulfill the green chemistry concept demands and have been proven excellent for the application in various fields. This review describes their application in different types of alkylation,C-,N-,O- andS-alkylation.P-alkylation has not yet been published within this scope. Not only have the authors in this study proven that DESs could be successfully applied for this specific type of reaction, but they have also offered an excellent insight into the mechanisms of their action.

Author(s):  
Ronak Warasthe

Abstract The number of Public-Private Partnerships in the education sector is growing in developing and emerging economies. Traditionally governments are the main financial contributor to education however, the involvement of the private sector is an increasing one. While more established in primary and secondary education, PPPs in tertiary education are a phenomenon rather slowly growing in the past decades (Patrinos, Barrera-Osorio, & Guaqueta, 2009). There are various concepts of PPPs in higher education each targeting different goals. In order to give an insight into different types of PPPs, the typology according to Mabizela has been briefly displayed and the case of a PPP in Namibia is given. The framework of the partnership was compiled to give an outlook on the practicability of partnerships. The paper exemplifies that both partners within a PPP can benefit from the added value they may generate for their target group. Thus, the benefit depends on quality, relevance and execution of the partnership.


Molecules ◽  
2018 ◽  
Vol 23 (10) ◽  
pp. 2666 ◽  
Author(s):  
Zhengning Ma ◽  
Zicheng Ma ◽  
Dawei Zhang

Pyrrole and its polysubstituted derivatives are important five-membered heterocyclic compounds, which exist alone or as a core framework in many pharmaceutical and natural product structures, some of which have good biological activities. The Van Leusen [3+2] cycloaddition reaction based on tosylmethyl isocyanides (TosMICs) and electron-deficient compounds as a substrate, which has been continuously developed due to its advantages such as operationally simple, easily available starting materials, and broadly range of substrates, is one of the most convenient methods to synthetize pyrrole heterocycles. In this review, we discuss the different types of two carbon synthons in the Van Leusen pyrrole reaction and give a summary of the progress of these synthesis methods in the past two decades.


Author(s):  
Gabriella Giannachi

This book traces the evolution of the archive across the centuries by looking at primitive, Medieval, Renaissance, Victorian and contemporary archives. Crucially, the book evidences the fluidity and potential inter-changeability between libraries, archives and museums. A number of case studies offer an insight into the operation of a variety of different types of archives, including cabinets of curiosity, archival artforms, architectures, performances, road-shows, time capsules, social media documentation practices, databases, and a variety of museological web-based heritage platforms. The archive is shown to play a crucial role in how individuals and social groups administer themselves through and within a burgeoning social memory apparatus. This is why at the heart of every industrial revolution thus far, the archive continues to contribute to the way we store, preserve and generate knowledge through an accumulation of documents, artifacts, objects, as well as ephemera and even debris. The archive has always been strategic for different types of economies, including the digital economy and the internet of things. Shown here to increasingly affect to the way we map, produce, and share knowledge, the apparatus of the archive, which allows us to continuously renew who we are in relation to the past, so that new futures may become possible, now effectively pervades almost every aspect of our lives.


1955 ◽  
Vol 1 ◽  
pp. 25-30

Numerous extensive studies of the space distribution of stars of different spectral types, based on star counts and colour measures, have in the past been published for different sections of the Milky Way.1 These studies have given information on the nearby obscuring clouds, and they have revealed marked differences between the distribution of different kinds of stars. They have not, however, given us the much desired insight into the large-scale features of the density distribution.


Synlett ◽  
2017 ◽  
Vol 28 (19) ◽  
pp. 2509-2516 ◽  
Author(s):  
Peter Jacobse ◽  
Marc-Etienne Moret ◽  
Robertus Klein Gebbink ◽  
Ingmar Swart

The field of on-surface synthesis has seen a tremendous development in the past decade as an exciting new methodology towards atomically well-defined nanostructures. A strong driving force in this respect is its inherent compatibility with scanning probe techniques, which allows one to ‘view’ the reactants and products at the single-molecule level. In this article, we review the ability of noncontact atomic force microscopy to study on-surface chemical reactions with atomic precision. We highlight recent advances in using noncontact atomic force microscopy to obtain mechanistic insight into reactions and focus on the recently elaborated mechanisms in the formation of different types of graphene nanoribbons.


Author(s):  
U. Aebi ◽  
P. Rew ◽  
T.-T. Sun

Various types of intermediate-sized (10-nm) filaments have been found and described in many different cell types during the past few years. Despite the differences in the chemical composition among the different types of filaments, they all yield common structural features: they are usually up to several microns long and have a diameter of 7 to 10 nm; there is evidence that they are made of several 2 to 3.5 nm wide protofilaments which are helically wound around each other; the secondary structure of the polypeptides constituting the filaments is rich in ∞-helix. However a detailed description of their structural organization is lacking to date.


TAPPI Journal ◽  
2015 ◽  
Vol 14 (1) ◽  
pp. 51-60
Author(s):  
HONGHI TRAN ◽  
DANNY TANDRA

Sootblowing technology used in recovery boilers originated from that used in coal-fired boilers. It started with manual cleaning with hand lancing and hand blowing, and evolved slowly into online sootblowing using retractable sootblowers. Since 1991, intensive research and development has focused on sootblowing jet fundamentals and deposit removal in recovery boilers. The results have provided much insight into sootblower jet hydrodynamics, how a sootblower jet interacts with tubes and deposits, and factors influencing its deposit removal efficiency, and have led to two important innovations: fully-expanded sootblower nozzles that are used in virtually all recovery boilers today, and the low pressure sootblowing technology that has been implemented in several new recovery boilers. The availability of powerful computing systems, superfast microprocessors and data acquisition systems, and versatile computational fluid dynamics (CFD) modeling capability in the past two decades has also contributed greatly to the advancement of sootblowing technology. High quality infrared inspection cameras have enabled mills to inspect the deposit buildup conditions in the boiler during operation, and helped identify problems with sootblower lance swinging and superheater platens and boiler bank tube vibrations. As the recovery boiler firing capacity and steam parameters have increased markedly in recent years, sootblowers have become larger and longer, and this can present a challenge in terms of both sootblower design and operation.


2019 ◽  
Vol 23 (11) ◽  
pp. 1214-1238 ◽  
Author(s):  
Navjeet Kaur ◽  
Pranshu Bhardwaj ◽  
Meenu Devi ◽  
Yamini Verma ◽  
Neha Ahlawat ◽  
...  

Due to special properties of ILs (Ionic Liquids) like their wide liquid range, good solvating ability, negligible vapour pressure, non-inflammability, environment friendly medium, high thermal stability, easy recycling and rate promoters etc. they are used in organic synthesis. The investigation for the replacement of organic solvents in organic synthesis is a growing area of interest due to increasing environmental issues. Therefore, ionic liquids have attracted the attention of chemists and act as a catalyst and reaction medium in organic reaction with high activity. There is no doubt that ionic liquids have become a major subject of study for modern chemistry. In comparison to traditional processes the use of ionic liquids resulted in improved, complimentary or alternative selectivities in organic synthesis. The present manuscript reported the synthesis of multiple nitrogen containing five-membered heterocyclic compounds using ionic liquids. This review covered interesting discoveries in the past few years.


2020 ◽  
Vol 20 (10) ◽  
pp. 908-920 ◽  
Author(s):  
Su-Min Wu ◽  
Xiao-Yang Qiu ◽  
Shu-Juan Liu ◽  
Juan Sun

Inhibitors of monoamine oxidase (MAO) have shown therapeutic values in a variety of neurodegenerative diseases such as depression, Parkinson’s disease and Alzheimer’s disease. Heterocyclic compounds exhibit a broad spectrum of biological activities and vital leading compounds for the development of chemical drugs. Herein, we focus on the synthesis and screening of novel single heterocyclic derivatives with MAO inhibitory activities during the past decade. This review covers recent pharmacological advancements of single heterocyclic moiety along with structure- activity relationship to provide better correlation among different structures and their receptor interactions.


2020 ◽  
Vol 16 (4) ◽  
pp. 454-486 ◽  
Author(s):  
Smita Verma ◽  
Vishnuvardh Ravichandiran ◽  
Nihar Ranjan ◽  
Swaran J.S. Flora

Nitrogen-containing heterocycles are one of the most common structural motifs in approximately 80% of the marketed drugs. Of these, benzimidazoles analogues are known to elicit a wide spectrum of pharmaceutical activities such as anticancer, antibacterial, antiparasitic, antiviral, antifungal as well as chemosensor effect. Based on the benzimidazole core fused heterocyclic compounds, crescent-shaped bisbenzimidazoles were developed which provided an early breakthrough in the sequence-specific DNA recognition. Over the years, a number of functional variations in the bisbenzimidazole core have led to the emergence of their unique properties and established them as versatile ligands against several classes of pathogens. The present review provides an overview of diverse pharmacological activities of the bisbenzimidazole analogues in the past decade with a brief account of its development through the years.


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