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Topic Review
The Lifetime of Organic Light-Emitting Diodes
Organic light-emitting diodes (OLEDs) have emerged as a promising technology for various applications owing to their advantages, including low-cost fabrication, flexibility, and compatibility. However, a limited lifetime hinders the practical application of OLEDs in electronic devices. OLEDs are prone to degradation effects during operation, resulting in a decrease in device lifetime and performance. 
  • 299
  • 29 Nov 2023
Topic Review
Naphthoquinones and Parkinson’s Disease
Parkinson’s disease (PD) is a pathology of neurological origin, degenerative of the region present in the central nervous system known as substantia nigra. Naphthoquinones are the most common type of quinones and compose an important series of natural distribution metabolites of plants, animals, fungi and bacteria.
  • 225
  • 17 Nov 2023
Topic Review
Hydrogen Sources in Catalytic Transfer Hydrogenation
Catalytic transfer hydrogenation has emerged as a pivotal chemical process with transformative potential in various industries. Unlike conventional direct hydrogenation, catalytic transfer hydrogenation offers numerous advantages, such as enhanced safety, cost-effective hydrogen donors, byproduct recyclability, catalyst accessibility, and the potential for catalytic asymmetric transfer hydrogenation, particularly with chiral ligands. Alcohols such as methanol and isopropanol are prominent hydrogen donors, demonstrating remarkable efficacy in various reductions. Formic acid offers irreversible hydrogenation, preventing the occurrence of reverse reactions, and is extensively utilized in chiral compound synthesis. Unconventional donors such as 1,4-cyclohexadiene and glycerol have shown a good efficiency in reducing unsaturated compounds, with glycerol additionally serving as a green solvent in some transformations. 
  • 540
  • 14 Nov 2023
Topic Review
C–H Functionalisation
C–H bond functionalisation describes the transformation of a C-H bonds into a C-X bonds (X = C, N, O, B, halides, among many others). The term is typically associated with transition metals in processes like C-H activation. However, other methods such as nitrene/carbene insertion and hydrogen atom transfer (HAT) can also be used to functionalise C-H bonds with varying selectivity and ability to introduce different functional groups depending on the method used. 
  • 167
  • 09 Nov 2023
Topic Review
Synthesis of Monoterpene Thiols
Thiols are one of the most convenient synthons in the synthesis of organosulfur compounds. The typical methods to prepare monoterpene thiols include the electrophilic addition of H2S or dithiols to the double bond of monoterpenes; nucleophilic substitution of halides; tosylates/mesylates obtained from corresponding monoterpene alcohols; thia-Michael addition of S-nucleophiles to α,β-unsaturated ketones; nucleophilic epoxide ring opening; nucleophilic substitution of the activated methylene protons; and reduction of sulfochlorides, dithiolanes, thiiranes, and sultones.
  • 262
  • 07 Nov 2023
Topic Review
Principles of Prototropic Equilibria
Prototropic tautomers always differ by the positions of labile proton(s) and π-electrons. The number of possible tautomeric forms is an internal property of the tautomeric molecule. It is a consequence of the number of labile protons and the number of conjugated tautomeric sites.
  • 411
  • 01 Nov 2023
Topic Review
Biosynthesis of Aurones
Natural products are a boundless source for the development of pharmaceutical agents against a wide range of human diseases. Accordingly, naturally occurring aurones possess various biological benefits, such as anticancer, antioxidant, antimicrobial, antidiabetic, anti-inflammatory, antiviral and neuroprotective effects. In addition, various studies have revealed that aurones are potential templates for the regulation of diabetes mellitus and its associated complications. Likewise, certain aurones and their analogues have been found to be remarkable kinase inhibitors of DARK2, PPAR-γ, PTPM1, AGE, α-amylase and α-glucosidase, which represents a promising approach for the treatment of chronic metabolic disorders such as diabetes. 
  • 362
  • 01 Nov 2023
Topic Review
Membrane-Active Topoisomeric Peptides
Bioactive peptides have been gaining recognition in various biomedical areas, such as intracellular drug delivery (cell-penetrating peptides, CPPs) or anti-infective action (antimicrobial peptides, AMPs), closely associated to their distinct mode of interaction with biological membranes. However, ordinary peptides formed by L-amino acids are easily decomposed by proteases in biological fluids. One way to sidestep this limitation is to use topoisomers, namely versions of the peptide made up of D-amino acids in either canonic (enantio) or inverted (retroenantio) sequence.
  • 140
  • 30 Oct 2023
Topic Review
Benzimidazole and Their Derivatives
Heterocyclic compounds are significant lead drug candidates based on their various structure–activity relationships (SAR), and their use in pharmaceutics is constantly developing. Benzimidazole (BnZ) is synthesized by a condensation reaction between benzene and imidazole. The BnZ structure consists of two nitrogen atoms embedded in a five-membered imide ring which is fused with a benzene ring. 
  • 328
  • 23 Oct 2023
Topic Review
Adaptive Self-Organizing Map Using Optimal Control
The self-organizing map (SOM), which is a type of artificial neural network (ANN), was formulated as an optimal control problem. Its objective function is to minimize the mean quantization error, and the state equation is the weight updating equation of SOM. Based on the objective function and the state equations, the Hamiltonian equation based on Pontryagin’s minimum principle (PMP) was formed. 
  • 172
  • 19 Oct 2023
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