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Topic Review
Organic Peroxide
Organic peroxides are organic compounds containing the peroxide functional group (ROOR′). If the R′ is hydrogen, the compounds are called hydroperoxides, which are discussed in that article. Peresters are the peroxy analog of esters and have general structure RC(O)OOR. The O−O bond of peroxides easily breaks, producing free radicals of the form RO• (the dot represents an unpaired electron). Thus, organic peroxides are useful as initiators for some types of polymerisation, such as the epoxy resins used in glass-reinforced plastics. MEKP and benzoyl peroxide are commonly used for this purpose. However, the same property also means that organic peroxides can either intentionally or unintentionally initiate explosive polymerisation in materials with unsaturated chemical bonds, and this process has been used in explosives. Organic peroxides, like their inorganic counterparts, are powerful bleaching agents.
  • 1.7K
  • 31 Oct 2022
Topic Review Peer Reviewed
Tautomerism of β-Diketones and β-Thioxoketones
The present overview concentrates on recent developments of tautomerism of β-diketones and β-thioxoketones, both in solution and in the solid state. In particular, the latter has been a matter of debate and unresolved problems. Measurements of 13C, 17O, and 2H chemical shifts have been used. Deuterium isotope effects on chemical shifts are proposed as a tool in the study of this problem. Photoconversion of β-diketones and β-thioxoketones are discussed in detail, and the incorporation of β-diketones into molecules with fluorescent properties is assessed. Finally, docking studies of β-diketones are scrutinized with an emphasis on correct tautomeric structures and knowledge about barriers to interconversion of tautomers.
  • 1.7K
  • 10 Mar 2023
Topic Review
Pincer Transition Metal Catalysts for Sustainability
Sustainable solutions are needed to avoid global warming and climate change. Homogeneous catalysis might play a fundamental role for this. Pincer-type complexes are promising in terms of stability, selectivity, efficiency and the use of mild reaction conditions. Pincer complexes have been used in many sustainable chemical reactions, for example hydrogen release and upconversion of CO2, N2, and biomass.
  • 1.7K
  • 08 Apr 2022
Topic Review
Heterocyclic Crown Ethers
Crown ethers are heterocyclic compounds present as cyclic oligomers in their simple form. These are extremely versatile compounds exhibiting higher binding affinity towards metal ions, including s-block and transition metal ions. For example, 18-crown-6 has a cavity that fits the size of 4f transition metal ions and has reflected exceptional attraction for complexation with the lanthanide ions.
  • 1.6K
  • 27 Jan 2022
Topic Review
Different Subclasses of Flavonoids
Flavonoids are natural compounds that are attracting great interest in the biomedical field thanks to the wide spectrum of their biological properties. Their employment as anticancer, anti-inflammatory, and antidiabetic drugs, as well as for many other pharmacological applications, is extensively investigated. 
  • 1.6K
  • 13 Mar 2023
Topic Review Peer Reviewed
Homocysteine Thiolactone: Biology and Сhemistry
Homocysteine thiolactone is a five-membered cyclic thioester of amino acid homocysteine. It is generated from homocysteine as a result of an error-editing reaction, principally, of methionyl-tRNA synthetase. An elevated level of homocysteine thiolactone is associated with cardiovascular diseases, strokes, atherosclerosis, neurological abnormalities, etc., presumably because it reacts to the side chain of protein lysine causing protein damage and autoimmune responses. It is not only an important metabolite but also a versatile building block for organic and bioorganic synthesis. This entry contains data on the homocysteine thiolactone formation, metabolism, toxicity mechanism in vivo, and the bioorganic chemistry applications as a powerful synthetic tool in polymer science, sustainable materials development, and probes. 
  • 1.6K
  • 13 Apr 2022
Topic Review
Molecular Iodine-Catalyzed Reactions
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 In continuation of our research on the synthesis of diverse organic molecules, we report here molecular iodine-catalyzed diverse synthetic processes. These methods are efficient and produce products in high yield. The success of molecular iodine-catalyzed reactions depends on the release of hydroiodic acid in the reaction media.
  • 1.5K
  • 01 Jun 2020
Topic Review
Fluorinated BODIPY Dyes
The synthesis of fluorine-containing small molecules has had numerous benefits of improving the quality and efficiency of many applications of these compounds. Compounds such as derivatives of boron-dipyrromethene (BODIPY) typically demonstrate signal wavelengths around 500 nm and 600 nm; however, it is more favorable to see these signals closer to 700 nm to improve fluorophore applications. For this reason, recent studies described further in the text demonstrate the applications of adding fluorine-based substituents and phenyl rings to the chemical designs, thus redshifting absorption and fluorescence wavelengths.
  • 1.5K
  • 30 Mar 2021
Topic Review
Copper Complexes as Topoisomerases Inhibitors
Organometallics, such as copper compounds, are cancer chemotherapeutics used alone or in combination with other drugs. A group of copper complexes exerts an effective inhibitory action on topoisomerases, which participate in the regulation of DNA topology. Copper complexes of topoisomerase inhibitors work by different molecular mechanisms that have repercussions on the cell cycle checkpoints and death effectors. 
  • 1.5K
  • 14 Oct 2020
Topic Review
Polymeric Nanocapsules
Polymer-based nanocapsules have been widely studied as a potential drug delivery system in recent years. Nanocapsules—as one of kind nanoparticle—provide a unique nanostructure, consisting of a liquid/solid core with a polymeric shell. This is of increasing interest in drug delivery applications. In this review, nanocapsules delivery systems studied in last decade are reviewed, along with nanocapsule formulation, characterizations of physical/chemical/biologic properties and applications. Furthermore, the challenges and opportunities of nanocapsules applications are also proposed.
  • 1.5K
  • 28 Oct 2020
Topic Review
Synthetic methods of phosphonopeptides
Phosphonopeptides are phosphorus analogues of peptides and have been widely applied as enzyme inhibitors and antigens to induce catalytic antibodies. Phosphonopeptides generally contain one aminoalkylphosphonic acid residue and include phosphonopeptides with C-terminal aminoalkylphosphonic acids and phosphonopeptides with a phosphonamidate bond. The phosphonamidate bond in the phosphonopeptides is generally formed via phosphonylation with phosphonochloridates, condensation with coupling reagents and enzymes, and phosphinylation followed by oxidation. Pseudo four-component condensation reaction of amides, aldehydes, alkyl dichlorophosphites, and amino/peptide esters is an alternative, convergent, and efficient strategy for synthesis of phosphonopeptides through simultaneous construction of aminoalkylphosphonic acids and formation of the phosphonamidate bond.
  • 1.5K
  • 16 Dec 2020
Topic Review
Direct Amidations of Carboxylic Acids with Amines
The prevalence of amides in biological systems and chemical fields such as polymers, materials and natural products drives continuous research on novel procedures to obtain these ubiquitous functional groups. Efforts to this purpose are mainly focused around the discovery of direct and catalytic methods that are more atom economic, safe and practical for diversified applications (e.g., organic, medicinal and peptide chemistries, material and polymer purposes, etc.), in accordance with green chemistry principles. 
  • 1.5K
  • 22 Feb 2023
Topic Review
Indane-1,3-Dione: From Synthetic Strategies to Applications
Indane-1,3-dione is a versatile building block used in numerous applications ranging from biosensing, bioactivity, bioimaging to electronics or photopolymerization. Indane-1-3-dione is among one of the most privileged scaffolds in chemistry, as the derivatives of this structure can find applications in various research fields ranging from medicinal chemistry, organic electronics, photopolymerization, to optical sensing and non-linear optical (NLO) applications. 
  • 1.5K
  • 29 Sep 2022
Topic Review
Beta Lactams and Products
Discovery and synthesis of penicillin and other beta-lactam antibiotics have received sustained attention. The use of β-lactam antibiotics is extensively documented in several thousand of publications. In modern times, microwave-induced reactions are also used extensively for the synthesis and stereochemical studies of diverse β-lactams. In this paper, the author describes a few crucial reactions that are performed toward the synthesis of β-lactams and products obtained from them under classical conditions as well as by domestic or automated microwave oven.
  • 1.5K
  • 28 Oct 2020
Topic Review
Structure, Spectral Properties and Chemistry of Spiropyrans
Spiropyrans (SP) are a well-studied class of photochromic compounds. These compounds are usually named in conformity with the IUPAC rules for nomenclature of heterocyclic spirocompounds, as derivatives of 1′,3′,3′-trimethyl-6-nitrospiro[2H-1-benzopyran-2,2′-indoline] or 1′,3′-dihydro-1′,3′,3′-trimethyl-6-nitrospiro[2H-1-benzopyran-2,2′-indole].
  • 1.5K
  • 11 Jul 2023
Topic Review
Egyptian Honeybee
The Egyptian honeybee (Apis mellifera lamarckii) is one of the honeybee subspecies known for centuries since the ancient Egypt civilization. The subspecies of the Egyptian honeybee is distinguished by certain traits of appearance and behavior that were well-adapted to the environment and unique in a way that it is resistant to bee diseases, such as the Varroa disease. The subspecies is different than those found in Europe and is native to southern Egypt.
  • 1.4K
  • 21 Oct 2022
Topic Review
Coumarin(Benzopyrone)-Fused Five-Membered Aromatic Heterocycles
Coumarins are a family of benzopyrones (1,2-benzopyrones or 2H-[1]benzopyran-2-ones), which represent an important family of oxygen-containing heterocycles, widely distributed in nature. Since coumarins have versatile applications, the synthesis trials of different structures of the coumarin-based scaffold were attempted. Among all the heterocycles built on α-pyrone moiety of coumarin, the furan ring was the only available structure in nature. Thus, it has inspired a lot of researchers to replace the oxygen with other heteroatoms. Wide varieties of heterocycles were constructed by a synthetic pathway to introduced furans, pyrroles, thiophenes, and selenophenes as a fused ring that characterized by a single heteroatom to the α-pyrone moiety of coumarin. 
  • 1.4K
  • 05 Apr 2021
Topic Review
1,3-Butadiene
1,3-Butadiene is the organic compound with the formula (CH2=CH)2. It is a colorless gas that is easily condensed to a liquid. It is important industrially as a monomer in the production of synthetic rubber. The molecule can be viewed as the union of two vinyl groups. It is the simplest conjugated diene. Although butadiene breaks down quickly in the atmosphere, it is nevertheless found in ambient air in urban and suburban areas as a consequence of its constant emission from motor vehicles. The name butadiene can also refer to the isomer, 1,2-butadiene, which is a cumulated diene with structure H2C=C=CH−CH3. This allene has no industrial significance.
  • 1.4K
  • 17 Oct 2022
Topic Review
Diels–Alder Cycloaddition Reactions
Diels–Alder cycloaddition reaction is one of the most powerful strategies for the construction of six-membered carbocyclic and heterocyclic systems, in most cases with high regio- and stereoselectivity. An insight into the most relevant advances on sustainable Diels–Alder reactions since 2010 is provided. Various environmentally benign solvent systems are discussed, namely bio-based derived solvents, polyethylene glycol, deep eutectic solvents, supercritical carbon dioxide, water and water-based aqueous systems.
  • 1.4K
  • 25 Mar 2022
Topic Review
Antimicrobial Activity of Calixarenes/Related Macrocycles
Calixarenes have been shown to have antimicrobial effects since the 1950s. These properties are exemplified through their applications as prodrugs, drug delivery agents and biofilm inhibitors. A particularly important development in recent years has been their ability to engage in multivalent interactions with proteins, thus inhibiting cellular aggregation.
  • 1.4K
  • 12 Dec 2020
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