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Topic Review
Three-Component Ring Transformation
The ring transformation is a synthetic method for cyclic products including transfer of the partial structure of a cyclic substrate to a reagent, constructing a new ring system. When one substrate and two reagents are used to form a cyclic structure, it is called three-component ring transformation.
  • 1.4K
  • 10 Mar 2021
Topic Review
Organic-Photovoltaics with Efficiency over 17%
When narrow band gap, non fullerene material Y6 or its derivatives are used as electron acceptors, the power conversion efficiency (PCE) of organic photovoltaic (OPV) has exceeded 18%. The PCE improvement of OPV is due to strong photon collection and low energy loss in the near-infrared range. At the same time, the ternary strategy is generally considered to be a convenient and effective means to improve the PCE of OPVs.
  • 1.3K
  • 26 Aug 2021
Topic Review
Visible-Light Photoredox Catalysis for the Thiol-Ene/Yne Reactions
Visible-light photoredox catalysis has been established as a popular and powerful tool for organic transformations owing to its inherent characterization of environmental friendliness and sustainability in the past decades. The thiol-ene/yne reactions, the direct hydrothiolation of alkenes/alkynes with thiols, represents one of the most efficient and atom-economic approaches for the carbon-sulfur bonds construction. In traditional methodologies, harsh conditions such as stoichiometric reagents or a specialized UV photo-apparatus were necessary suffering from various disadvantages. In particular, visible-light photoredox catalysis has also been demonstrated to be a greener and milder protocol for the thiol-ene/yne reactions in recent years. Additionally, unprecedented advancements have been achieved in this area during the past decade.
  • 1.3K
  • 11 Feb 2022
Topic Review
General Methods of Pyruvic Acid Production
Pyruvic acid has numerous applications in the food, chemical, and pharmaceutical industries. General methods of pyruvic acid production include chemical method and biotechnological methods
  • 1.3K
  • 12 Jan 2023
Topic Review
Enantioselective Catalytic C-H Amidations
The crucial role played by compounds bearing amide functions, not only in biological processes but also in several fields of chemistry, life polymers and material sciences, has brought about many significant discoveries and innovative approaches for their chemical synthesis. Within this context, and following the development of C-H functionalization strategies, C-H amidation reactions have only recently emerged as valuable approaches for the construction of amide functions. These methodologies have been successfully used for both C(sp2)- and C(sp3)-H activations and blossoming synthetic applications have appeared in the last two years (2019-2020 timeframe).
  • 1.3K
  • 15 Apr 2021
Topic Review
Fused 1,5-naphthyridines
Heterocyclic nitrogen compounds, including fused 1,5-naphthyridines, have versatile applications in synthetic organic chemistry and play an important role in the field of medicinal chemistry, as many of them have a wide range of biological activities. In this review, a wide range of synthetic protocols for the construction of this scaffold are presented. For example, Friedländer, Skraup, Semmlere-Wolff, and hetero-Diels-Alder, among others, are well known classical synthetic protocols used for the construction of the main 1,5-naphthyridine scaffold. These syntheses are classified according to the nature of the cycle fused to the 1,5-naphthyridine ring: carbocycles, nitrogen heterocycles, oxygen heterocycles, and sulphur heterocycles. In addition, taking into account the aforementioned versatility of these heterocycles, their reactivity is presented as well as their use as a ligand for metal complexes formation. Finally, those fused 1,5-naphthyridines that present biological activity and optical applications, among others, are indicated.
  • 1.3K
  • 31 Aug 2020
Topic Review
Fermentation (Food)
Fermentation typically refers to the conversion of sugar to alcohol using yeast. However, a more appropriate definition would be the chemical conversion of carbohydrates into alcohols or acids. The process is used to produce wine, beer and leavened bread, but fermentation is also employed in preservation to create lactic acid in sour foods such as pickled cucumbers, kimchi and yogurt. The science of fermentation is known as zymology.
  • 1.2K
  • 14 Apr 2023
Topic Review
Aromatic Hydrocarbon
An aromatic hydrocarbon or arene (or sometimes aryl hydrocarbon) is a hydrocarbon with sigma bonds and delocalized pi electrons between carbon atoms forming a circle. In contrast, aliphatic hydrocarbons lack this delocalization. The term "aromatic" was assigned before the physical mechanism determining aromaticity was discovered, and referred simply to the fact that many such compounds have a sweet or pleasant odour; however, not all aromatic compounds have a sweet odour, and not all compounds with a sweet odour are aromatic. The configuration of six carbon atoms in aromatic compounds is called a "benzene ring", after the simplest possible such hydrocarbon, benzene. Aromatic hydrocarbons can be monocyclic (MAH) or polycyclic (PAH). Not all aromatic compounds are benzene-based; aromaticity can also manifest in heteroarenes, which follow Hückel's rule (for monocyclic rings: when the number of its π electrons equals 4n + 2, where n = 0, 1, 2, 3, ...). In these compounds, at least one carbon atom is replaced by one of the heteroatoms oxygen, nitrogen, or sulfur. Examples of non-benzene compounds with aromatic properties are furan, a heterocyclic compound with a five-membered ring that includes a single oxygen atom, and pyridine, a heterocyclic compound with a six-membered ring containing one nitrogen atom.
  • 1.2K
  • 25 Nov 2022
Topic Review
Cross-Coupling-Reaction of Copper Carbene Intermediate with Terminal Alkyne
Copper-catalyzed cross-coupling reaction of a copper carbene intermediate with terminal alkynes was one of the most powerful protocols for the construction of C–C bonds. However, in early works, a mixture of alkynoates and allenoates was generated in combined moderate yields under harsh reaction conditions. Until 2004, Fu reported the first example of the copper-catalyzed coupling reaction of terminal alkynes with diazo esters or diazo amides to yield 3-alkynoate or 3-butynamide products selectively with minimal amount of allene byproducts under no-basic conditions. Consequently, a variety of copper-catalyzed coupling reactions of terminal alkynes with various carbene precursors have been developed independently.
  • 1.2K
  • 30 May 2022
Topic Review
Green Solvents
Green extraction techniques are more and more relevant due to major sustainable goals set by the United Nations. Greener extraction processes are being designed through the use of unconventional extraction techniques and green solvents, resulting in less hazardous processes which, consequently, reduces environmental impacts.
  • 1.2K
  • 01 Aug 2023
Topic Review
Novichok Agent
A Novichok agent (Russian: Новичо́к, "newcomer", "novice", "newbie") is a group of nerve agents, some of which are binary chemical weapons. The agents were developed at the GosNIIOKhT state chemical research institute by the Soviet Union and Russia between 1971 and 1993.[lower-alpha 1] Some Novichok agents at STP are solids while others are liquids. It is thought that dispersal for the solids is possible by ultrafine powder. Russian scientists who developed the nerve agents claim they are the deadliest ever made, with some variants possibly five to eight times more potent than VX, and others up to ten times more potent than soman. As well as Russia, Novichok agents have been known to be produced in Iran. In the 21st century, Novichok agents came to public attention after they were used to poison opponents of the Russian government, including the Skripals and two others in Amesbury, UK (2018) and Alexei Navalny (2020), but civil poisonings with this substance have been known since at least 1995. In November 2019, the Organisation for the Prohibition of Chemical Weapons (OPCW), which is the executive body for the Chemical Weapons Convention (CWC), added the Novichok agents to "list of controlled substances" of the CWC "in one of the first major changes to the treaty since it was agreed in the 1990s" in response to the 2018 poisonings in the UK.
  • 1.2K
  • 11 Nov 2022
Topic Review
Acridine
Acridine, an alkaloid from anthracene, also known by the names of 10-azaanthracene, dibenzopyridine, 2,3,5,6-dibenzopyridine, and its derivatives or analogs, have a great potential to be an efficient class of excellent inhibitor. The phenomenon of corrosion threatens metallic components, human safety, and the economy. Despite being eco-friendly and promising as a corrosion inhibitor, acridine has not been explored to its full potential. 
  • 1.2K
  • 09 Nov 2022
Topic Review
Thia-Michael Reaction
While the Michael addition has been employed for more than 130 years for the synthesis of a vast diversity of compounds, the reversibility of this reaction when heteronucleophiles are involved has been generally less considered. First applied to medicinal chemistry, the reversible character of the hetero-Michael reactions has been explored for the synthesis of Covalent Adaptable Networks (CANs), in particular the thia-Michael reaction and more recently the aza-Michael reaction. In these cross-linked networks, exchange reactions take place between two Michael adducts by successive dissociation and association steps. In order to understand and precisely control the exchange in these CANs, it is necessary to get an insight into the critical parameters influencing the Michael addition and the dissociation rates of Michael adducts by reconsidering previous studies on these matters. 
  • 1.2K
  • 28 Nov 2022
Topic Review
Synthesis of the Coumarin Core
Coumarin compounds are attractive organic compounds with many practical applications. Among them there are compounds with biological activity, pharmaceuticals, agrochemicals, dyes, and optoelectronic materials. For this reason, enormous and continuous attempts were made to develop new synthetic pathways and protocols to facilitate the key cyclization reaction of heterocyclic ring and its regioselective functionalization. Of the numerous proposed reactions for the preparation of coumarins, those based on transition metal catalysts have been frequently used recently. Such processes as intramolecular and intermolecular hydroarylation of alkenes or alkynes can be mentioned among the most effective reactions proceeding via the activation of the C–H bond. Knowledge about the mechanistic foundations of catalytic processes seems to be of significant importance in order to improve them and simplify the conditions. Direct functionalization of the coumarin skeleton seems to be one of the more difficult tasks in recent times.
  • 1.2K
  • 23 Mar 2022
Topic Review
Heating's Influence Trans Fatty Acid in Oils
Consumption of trans fatty acids (TFA) is associated with adverse health outcomes and places a considerable burden on morbidity and mortality globally. TFA may be generated by common cooking practices and hence contribute to daily dietary intake. Heating edible oils to common cooking temperatures (≤200 °C) has minimal effect on TFA generation whereas heating to higher temperatures can increase TFA level. 
  • 1.2K
  • 24 May 2022
Topic Review
Coumarin Derivatives from Marine World
Coumarin and its derivatives have significantly attracted the attention of medicinal chemists and chemical biologists due to their huge range of biological, and in particular, pharmacological properties. Interesting families of coumarins have been found from marine sources, which has accelerated the drug discovery process by inspiring innovation or even by the identification of analogues with remarkable biological properties.
  • 1.2K
  • 13 Jan 2023
Topic Review
Bio-catalysis in Multicomponent Reactions
Enzyme catalysis is a very active research area in organic chemistry, because biocatalysts are compatible with and can be adjusted to many reaction conditions, as well as substrates. Their integration in multicomponent reactions (MCRs) allows for simple protocols to be implemented in the diversity-oriented synthesis of complex molecules in chemo-, regio-, stereoselective or even specific modes without the need for the protection/deprotection of functional groups.
  • 1.2K
  • 28 Dec 2020
Topic Review
Molecules of the Week
"Molecules of the Week" is a new project to collect and show the discovery of novel molecules, compounds as well as the researchers' story behind it.
  • 1.2K
  • 05 Nov 2021
Topic Review
Synthesis of Thienothiophenes
Thienothiophenes (TT), formed by two annulated thiophene rings, represent fully the planar system, whose embedding into a molecular architecture can significantly improve/alter the fundamental properties of organic, π-conjugated materials. 
  • 1.2K
  • 21 Nov 2022
Topic Review
Synthesis of Anticancer Polyaromatic Compounds
Bimal Krishna Banik Department of Mathematics and Natural Sciences, College of Sciences and Human Studies, Deanship of Research, Prince Mohammad Bin Fahd University, Al Khobar 31952, KSA; Email: bimalbanik10@gmail.com; bbanik@pmu.edu.sa Synthesis of several polycyclic aromatic compounds is described. Some of these agents have demonstrated selective anticancer activities in vitro and in animal model. Preliminary mechanistic investigations about the cause of bioactivity are also performed.
  • 1.1K
  • 01 Jun 2020
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