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Topic Review
Triarylmethyl Radical-Based High-Efficiency OLED
Perchlorotrityl radical (PTM), tris (2,4,6-trichlorophenyl) methyl radical (TTM), (3,5-dichloro-4-pyridyl) bis (2,4,6 trichlorophenyl) methyl radical (PyBTM), (N-carbazolyl) bis (2,4,6-trichlorophenyl) methyl radical (CzBTM), and their derivatives are stable organic radicals that exhibit light emissions at room temperature. Since these triarylmethyl radicals have an unpaired electron, their electron spins at the lowest excited state and ground state are both doublets, and the transition from the lowest excited state to the ground state does not pose the problem of a spin-forbidden reaction. When used as OLED layers, these triarylmethyl radicals exhibit unique light-emitting properties, which can increase the theoretical upper limit of the OLED’s internal quantum efficiency (IQE) to 100%.
  • 1.1K
  • 15 Apr 2022
Topic Review
Heterogeneous Catalysis for Selective Hydrogenation of Oximes
The synthesis of many biologically active compounds is not complete without transforming the carbonyl group into an amino group, carried out by the reaction of nucleophilic substitution with hydroxylamine at the carbonyl carbon atom and further reduction of the C–N and N–O bonds. This method eliminates nitrating agents that exhibit oxidizing properties and may cause undesirable effects on other structural fragments of complex molecules. Selective hydrogenation of oximes over heterogeneous catalysts is still one of the most useful and challenging reactions in synthetic organic chemistry to obtain amines and hydroxylamines since the 1920s when the Adam’s catalyst was first used for this reaction. 
  • 1.1K
  • 28 Dec 2022
Topic Review
Zn(II) Hydrazone Complexes
Compound Name: (E)-N,N,N-trimethyl-2-oxo-2-(2-(1-(thiazol-2-yl)ethylidene)hydrazinyl)ethan-1-aminium di(thiocyanato-κN) zink(II) dihydrate.
  • 1.1K
  • 29 Dec 2020
Topic Review
Carbon-Oxygen (C–O) Bond Formation
Various noble metal and nonprecious metal or metal oxide nanoparticles have been utilized to exploit the C–H activation process to promote the formation of a new C–O bond and access alcohols or carbonyls. 
  • 1.1K
  • 03 Jan 2023
Topic Review
Synthesis of Ilamycins/Rufomycins and Cyclomarins
Ilamycins/rufomycins and cyclomarins are marine cycloheptapeptides containing unusual amino acids. Produced by Streptomyces sp., these compounds show potent activity against a range of mycobacteria, including multidrug-resistant strains of Mycobacterium tuberculosis. The cyclomarins are also very potent inhibitors of Plasmodium falciparum. Biosynthetically the cyclopeptides are obtained via a heptamodular nonribosomal peptide synthetase (NRPS) that directly incorporates some of the nonproteinogenic amino acids. A wide range of derivatives can be obtained by fermentation, while bioengineering also allows the mutasynthesis of derivatives, especially cyclomarins. Other derivatives are accessible by semisynthesis or total synthesis, reported for both natural product classes.
  • 1.1K
  • 03 Sep 2021
Topic Review
Different Schiff Bases
Schiff bases are a vast group of compounds characterized by the presence of a double bond linking carbon and nitrogen atoms, the versatility of which is generated in the many ways to combine a variety of alkyl or aryl substituents.
  • 1.1K
  • 18 Feb 2022
Topic Review
Dihydropyrrolo[1,2-a]Pyrazinones
Dihydropyrrolo[1,2-a]pyrazinone rings are a class of heterocycles present in a wide range of bioactive natural products and analogues thereof. As a direct result of their bioactivity, the synthesis of this privileged class of compounds has been extensively studied. This review provides an overview of these synthetic pathways.
  • 1.1K
  • 09 Jun 2021
Topic Review
HS-SPME-GC–MS Volatile Profile Characterization of Peach
The volatile compounds of eight peach varieties (Prunus persica L.)—“Filina”, “Gergana”, “Ufo-4”, “July lady”, “Laskava”, “Flat Queen”, “Evmolpiya”, and “Morsiani 90”—growing in Bulgaria were analyzed for the first time. Gas chromatography–mass spectrometry (GC–MS) analysis and the HS-SPME technique revealed the presence of 65 volatile compounds; the main identified components were aldehydes, esters, and fatty acids. According to the provided principal component analysis (PCA) and hierarchical cluster analysis (HCA), the relative quantities of the identified volatile compounds depended on the studied peach variety. The results obtained could be successfully applied for the metabolic chemotaxonomy of peaches.
  • 1.1K
  • 10 Feb 2022
Topic Review
Stevia Genus
Phytochemistry and biological activities update of Stevia genus.
  • 1.1K
  • 21 May 2021
Topic Review
Polyester-Based Coatings for Corrosion Protection
Polyesters are synthetic resins formed by an esterification chemical reaction with some occurring naturally. In addition, there are different orientations of polyesters and, hence, different classifications. The classifications aid in determining the processing, curing kinetics, and overall applications of the resin. Saturated, unsaturated polyesters (UPs) and alkyd resins are the main classifications of polyesters; however, vinyl esters are also classified as polyesters since they have a di-ester group. Vinyl esters are based on the combination of an epoxy resin with an unsaturated polymer; they have excellent properties when compared to saturated, unsaturated-type polyesters and alkyd resins. Developments of non-toxic polyester-based coatings have the potential to address a wide range of pollution problems, such as air pollution and water pollution, generated during the production of conventional polyester coatings. The anticorrosion properties of polyester resin modified by nanocomposites intended for steel are of interest. The goal is to produce a bio-based polyester coating with minimal cost by implementing natural products as well as modifying with nanomaterials. 
  • 1.1K
  • 04 Nov 2022
Topic Review
Asymmetric Synthesis of BINOL Derivatives
The chirality resulting from restricted rotation around a single bond is called atropisomerism (axial chirality). This phenomenon was first described by Christie and Kenner in 1922 when investigating the biaryl 6,6’-dinitro-2,2’-diphenic acid, and the term “atropisomer”, derived from the Greek where “a” means “not” and “tropes” means “turn”, was created by Kuhn. Atropisomers belong to the class of axially chiral compounds; however, here, the enantiomers exist due to restricted rotation around a single bond. Axial chirality has also been considered as an important structural element of many natural products and bioactive compounds, whose enantiomers generally exhibit different pharmacological activities and metabolic processes in vivo and in vitro.
  • 1.1K
  • 10 Jan 2023
Topic Review
Synthetic Applications of Aziridinium Ions
Aziridines are three-membered cyclic organic heterocyclic compounds with one nitrogen atom in the ring. 
  • 1.0K
  • 27 Apr 2021
Topic Review
Dietary Plant Polyphenols
Dietary plant polyphenols are natural bioactive compounds that are increasingly attracting the attention of food scientists and nutritionists because of their nutraceutical properties. 
  • 1.0K
  • 09 Jun 2021
Topic Review
Irosustat: Clinical Steroid Sulfatase Inhibitor
Irosustat: (6-oxo-8,9,10,11-tetrahydro-7H-cyclohepta[c]chromen-3-yl) sulfamate; 6-oxo-8,9,10,11-tetrahydro-7H-cyclohepta-(c)(1)benzopyran-3-O-sulfamate; also known as STX64, 667 Coumate, BN83495, Oristusane is a tricyclic synthetic clinical drug of the aryl sulfamate ester class, designed mainly for applications in oncology as a steroid sulfatase inhibitor and has shown clinical benefit in patients.
  • 1.0K
  • 09 Feb 2021
Topic Review
Thienopyrimidine
Thienopyrimidine emerges as an attractive scaffold in medicinal chemistry with a wide array of pharmacological properties, such as antibacterial, antifungal, antiparasitic and antiviral. Considering the fusion between pyrimidine and thiophene rings, three different thienopyrimidines can be obtained, namely thieno[2,3-d]pyrimidines, thieno[3,2-d]pyrimidines and thieno[3,4-d]pyrimidines. Different synthetic pathways involving the construction of the pyrimidine or the thiophene ring were reported in the literature to access polysubstituted thienopyrimidines. In these approaches, the synthetic strategies mostly involved the synthesis of a thienopyrimidin-4-one derivative, where position 4 could be modified via further functionalization.
  • 1.0K
  • 13 Jan 2022
Topic Review
Hydrosilylation Reactions Catalyzed by Rhenium
Hydrosilylation is a very versatile transformation consisting of the addition of a hydrosilane (H-SiR3) to an unsaturated bond. Organosilicon compounds have found widespread applications in our daily lives in silicon-based materials such as silicon rubbers, adhesives, paper release coating, and so forth. In addition, hydrosilylation is an atom economic reaction to access valuable organosilane intermediates for fine chemical synthesis
  • 1.0K
  • 20 May 2021
Topic Review
Ionic Liquids in Liquid–Liquid Microextraction
Ionic liquids (ILs) are a new chemical medium and soft functional material developed under the framework of green chemistry and possess many unique properties, such as low melting points, low-to-negligible vapor pressures, excellent solubility, structural designability and high thermal stability. 
  • 1.0K
  • 26 Jul 2022
Topic Review
Triazole-Modified Nucleic Acids
Locked nucleic acids (LNAs) are widely used in RNA therapeutics as LNA-modified antisense oligonucleotides. From the structural point of view, LNA is an RNA derivative in which the ribose ring is constrained by a methylene linkage between the 2′-oxygen and the 4′-carbon. This conformational restriction causes an increased binding affinity to complementary DNA and RNA sequences, but the susceptibility to RNase H should be optimized for individual applications.
  • 1.0K
  • 17 Jun 2021
Topic Review
Palladium-Catalyzed Carboxylation Reactions
The efficient incorporation of carbon dioxide into an organic substrate (carboxylation) under catalytic conditions to give high value added molecules is one of the most important and fascinating areas of current organic synthesis. Carbon dioxide is a nonflammable, inexpensive and largely available C-1 feedstock. In fact, it allows converting an important waste (it is well known that carbon dioxide is produced in enormous amounts from the combustion of fossil fuels for the production of energy) into a variety of useful compounds, which can find application as fuels or in the pharmaceutical or material fields.
  • 1.0K
  • 06 Jan 2022
Topic Review
Diaziridine
Diaziridine is a high strained three-membered heterocycle with two nitrogen atoms that plays an important role as one of the most important precursors of diazirine photoaffinity probes. Recent research trends can be grouped into three categories, based on whether they have examined non-substituted, N-monosubstituted, or N,N-disubstituted diaziridines.
  • 1.0K
  • 17 Aug 2021
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