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Topic Review
1,2-cis glycosylation
Controlling the stereoselectivity of 1,2-cis glycosylation is one of the most challenging tasks in the chemical synthesis of glycans. There are various 1,2-cis glycosides in nature, such as α-glucoside and β-mannoside in glycoproteins, glycolipids, proteoglycans, microbial polysaccharides, and bioactive natural products. In the structure of polysaccharides such as α-glucan, 1,2-cis α-glucosides were found to be the major linkage between the glucopyranosides. Various regioisomeric linkages, 1→3, 1→4, and 1→6 for the backbone structure, and 1→2/3/4/6 for branching in the polysaccharide as well as in the oligosaccharides were identified. To achieve highly stereoselective 1,2-cis glycosylation, including α-glucosylation, a number of strategies using inter- and intra-molecular methodologies have been explored.
  • 563
  • 09 Aug 2023
Topic Review
Terpolymerization of CO2
The terpolymerization of CO2 with epoxides and organic anhydrides or cyclic esters offers the possibility, combining the ROCOP with ring-opening polymerization (ROP), to access a wide range of materials containing polycarbonate and polyester segments along the polymer chain, showing enhanced properties with respect to the simple APC. This review will cover the last advancements in the field, evidencing the crucial role of the catalytic system in determining the microstructural features of the final polymer.
  • 560
  • 27 Aug 2021
Topic Review
Synthesis Approaches of Aza-Dibenzocyclooctyne Derivatives
Cyclooctyne molecules have found wide applications in the strain-promoted azide–alkyne cycloaddition (SPAAC) reactions, which avoid the biotoxicity caused by the use of Cu(I) catalysts. Among the various cyclooctyne systems, dibenzocyclooctyne (DBCO) series have displayed the highest reaction activity.
  • 559
  • 06 May 2023
Topic Review
The Pioneers of Carotenoid Chemistry: László Zechmeister
László Zechmeister, one of the most important pioneers of carotenoid chemistry, died 50 years ago. He founded a carotenoid research group in Pécs (Hungary), which is the only place in the world where carotenoid research has been conducted continuously over the past 95 years.
  • 558
  • 24 Apr 2022
Topic Review
Redox Active Organic-Carbon Composites for Supercapacitors
The redox active organic compounds and composites should meet the criteria of capacitive nature and have high chemical and electrochemical stability. Pseudocapacitive behavior that shows ideal characteristics as reflected in linear galvanostatic charge-discharge and rectangular voltammograms need to be targeted. Battery-like bulk faradaic behavior, which is not ideal for high-power (rate) capacitive applications but is often reported for supercapacitors, should be differentiated.
  • 554
  • 17 Jan 2022
Topic Review
Multienzymatic Processes Involving Baeyer–Villiger Monooxygenases
Baeyer–Villiger monooxygenases (BVMOs) are flavin-dependent oxidative enzymes capable of catalyzing the insertion of an oxygen atom between a carbonylic Csp2 and the Csp3 at the alpha position, therefore transforming linear and cyclic ketones into esters and lactones. These enzymes are dependent on nicotinamides (NAD(P)H) for the flavin reduction and subsequent reaction with molecular oxygen. BVMOs can be included in cascade reactions, coupled to other redox enzymes, such as alcohol dehydrogenases (ADHs) or ene-reductases (EREDs), so that the direct conversion of alcohols or α,β-unsaturated carbonylic compounds to the corresponding esters can be achieved. 
  • 553
  • 11 May 2021
Topic Review
Chemiluminescence Detection/Quantification of Haloaromatic Compounds
Polyhaloaromatic compounds (XAr) have been found world-wide in pesticides, pharmaceuticals, flame retardants and personal care products. Most of these compounds are persistent and widely existing in the environment because of their recalcitrant properties in the soil and water.  They are potentially carcinogenic to organisms and may induce serious risks to the ecosystem. Therefore, it is important to detect and quantify these ubiquitous XAr in the environment, and to monitor their degradation kinetics during the treatment of these recalcitrant pollutants. Chemiluminescence (CL) is a kind of light emission from complicated chemical reactions, during which high-energy excited-states can be generated and energy is released. CL analysis can be used to detect and quantify the specific compounds that determine the generation of CL emission. It has been recently discovered that unprecedent CL emission could be produced during the degradation of XAr mediated by advanced oxidation processes (AOPs), and a novel, rapid and sensitive CL-based analytical method was developed to not only detect XAr, but also monitor their degradation kinetics. For this distinct CL-based analytical method on the detection and measurement of XAr, it exhibits the excellent properties of relatively simple, rapid, sensitive, without complicated pretreatment.
  • 545
  • 15 Jun 2021
Topic Review
Secondary Metabolites Isolated from Chilean Marine Algae
Chile is in the extreme southwestern part of America, and it has an extreme length, of approximately 4300 km that increases to 8000 km considering the Chilean Antarctic Territory. Despite the large extent of its coastal territory and the diversity of geographic environments and climates associated with Chilean coasts, the research on marine resources in Chile has been rather scarce. 
  • 540
  • 08 Jun 2022
Topic Review
Synthesis of Pyrazolo pyrano oxazoles
A simple and efficient synthetic route to the novel 3a,4-dihydro-3H,7H- and 4H,7H-pyrazolo[4′,3′:5,6]pyrano[4,3-c][1,2]oxazole ring systems from 3-(prop-2-en-1-yloxy)- or 3-(prop-2-yn-1-yloxy)-1H-pyrazole-4-carbaldehyde oximes has been developed by employing the intramolecular nitrile oxide cycloaddition (INOC) reaction as the key step.
  • 530
  • 06 Feb 2023
Topic Review
Carbon-Based Iron Catalysts for Organic Synthesis
Carbon-based iron catalysts combining the advantages of iron and carbon material are efficient and sustainable catalysts for green organic synthesis.
  • 529
  • 01 Feb 2023
Topic Review
History of the Greatest “Minor” Cannabinoid
Cannabis (Cannabis sativa L.) is an outstanding source of bioactive natural products, with more than 150 different phytocannabinoids isolated; however, studies of their bioactivity have historically concentrated on the so-called “big four” [∆9-tetrahydrocannabinol, cannabidiol, cannabigerol and cannabichromene]. Among the remaining products, which have traditionally been referred to as “minor cannabinoids”, cannabinol stands out for its important repercussions and implications on the global scientific landscape. 
  • 525
  • 03 Nov 2022
Topic Review
Deep Eutectic Systems as Alternative Solvents
Chemists in the medicinal chemistry field are constantly searching for alternatives towards more sustainable and eco-friendly processes for the design and synthesis of drug candidates. The pharmaceutical industry is one of the most polluting industries, having a high E-factor, which is driving the adoption of more sustainable processes not only for new drug candidates, but also in the production of well-established active pharmaceutical ingredients. Deep eutectic systems (DESs) have emerged as a greener alternative to ionic liquids, and their potential to substitute traditional organic solvents in drug discovery has raised interest among scientists. 
  • 519
  • 28 Feb 2024
Topic Review
Metal-Organic Framework Based Nanomaterials Applied in Battery Cathodes
Metal-Organic Frameworks have attracted profound attention the latest years for use in environmental applications. They can offer a broad variety of functions due to their tunable porosity, high surface area and metal activity centers. Specifically, MOFs have been investigated thoroughly as potential materials hosting the oxidizing agent in the cathode electrode of several battery systems such as Lithium Batteries, Metal-Ion Batteries and Metal-Air Batteries. 
  • 508
  • 19 Sep 2022
Topic Review
Electrochemical Methodologies for Plant and Fruit Extracts
The growing research interests in the applications of plant and fruit extracts (synthetic/stabilization materials for the nanomaterials, medicinal applications, functional foods, and nutraceuticals) have led to the development of new analytical techniques to be utilized for identifying numerous properties of these extracts. One of the main properties essential for the applicability of these plant extracts is the antioxidant capacity (AOC) that is conventionally determined by spectrophotometric techniques. Nowadays, electrochemical methodologies are emerging as alternative tools for quantifying this particular property of the extract. These methodologies address numerous drawbacks of the conventional spectroscopic approach, such as the utilization of expensive and hazardous solvents, extensive sample pre-treatment requirements, long reaction times, low sensitivity, etc. 
  • 505
  • 12 Jul 2022
Topic Review
Triacontanol
1-Triacontanol is a fatty alcohol of the general formula C30H62O, also known as melissyl alcohol or myricyl alcohol. It is found in plant cuticle waxes and in beeswax. Triacontanol is a growth stimulant for many plants, most notably roses, in which it rapidly increases the number of basal breaks. 1-Triacontanol or n-triacontanol is a natural plant growth regulator. It has been widely used to enhance the yield of various crops around the world, mainly in Asia. . Triacontanol has been reported to increase the growth of plants by enhancing the rates of photosynthesis, protein biosynthesis, the transport of nutrients in a plant and enzyme activity, reducing complex carbohydrates among many other purposes. The fatty alcohol appears to increase the physiological efficiency of plant cells and boost the potential of the cells responsible for the growth and maturity of a plant.
  • 504
  • 21 Nov 2022
Topic Review
Synthesis of the 1,2,3-Dithiazole Scaffold
The 1,2,3-dithiazole is an underappreciated scaffold in medicinal chemistry despite possessing a wide variety of nascent pharmacological activities. The scaffold has a potential wealth of opportunities within these activities and further afield. The synthesis of Appel salt 1 acted as a catalyst to the field and granted access to many 1,2,3-dithiazole derivatives, and to other heterocycles incorporating sulfur and nitrogen atoms.
  • 500
  • 12 Apr 2023
Topic Review
Copper-Catalyzed/Hypervalent Iodine-Mediated Functionalization of Unactivated Compounds
The functionalization of unactivated substrates through the combination of copper catalysts and hypervalent iodine reagents represents a versatile tool in organic synthesis to access various classes of compounds. The hypervalent iodine derivatives can be used simply as oxidizing agents to regenerate the catalytic species or they can associate the functionalization of the starting material.
  • 497
  • 29 Dec 2023
Topic Review
Iridium-Catalyzed Difunctionalization of Alkenes
Alkenes and their related analogs are a class of ideal starting materials for the construction of complex molecules, because they are readily available in bulk quantities from renewable resources and petrochemical feedstocks. They are also considered to be the most cost-effective and widely used raw material for organic synthesis, and due to the diversity of functional groups, they are used very frequently in different chemical industries. As basic functionalities, the exploration of efficient methods for the selective functionalization of alkenes has been a continuous pursuit throughout the history of organic chemistry.
  • 495
  • 12 Jul 2023
Topic Review
Teucrium Taxa Used in Kurdistan Region
Herbal medicine is still widely practiced in the Kurdistan Region, Iraq, especially by people living in villages in mountainous regions. Seven taxa belonging to the genus Teucrium (family Lamiaceae) are commonly employed in the Kurdish traditional medicine, especially to treat jaundice, stomachache and abdominal problems. Teucrium L. is the second-largest genus of the subfamily Ajugoideae in the family Lamiaceae (Labiatae), with a subcosmopolitan distribution and more than 430 taxa with accepted names. Mild climate regions, such as the Mediterranean and the Middle East areas, contain about 90% of the total Teucrium taxa. 
  • 492
  • 27 May 2022
Topic Review
Microwave-Assisted Post-Ugi Reactions for the Synthesis of Polycycles
Microwave-assisted post-Ugi reactions have been employed for the synthesis of diverse polycycles. From commercially available starting materials, transition metal-catalyzed or transition metal-free transformations are performed in an efficient, rapid, and step-economical manner. With the help of microwave irradiation, linear Ugi-adducts are converted into more complex drug-like polycycles with high chemo-, regio-, and stereoselectivity, exhibiting the robustness and potential of this strategy and unfolding a large window for organic synthesis.
  • 492
  • 30 May 2022
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