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Topic Review
Chlorine in an Organic Molecule
Due to the electronic configuration of the atom and charge of the nucleus, the chlorine in organic molecules can exert a variety of effects. It can depart as a chloride anion in the process of substitution and elimination, facilitates the abstraction of protons and stabilizes generated carbanions, exerts moderate stabilizing effect of carbenes, carbocations and radicals. There are frequent cases where chlorine substituent promotes more than one transformation. 
  • 936
  • 17 Jan 2024
Topic Review
Polyphenols in Humiria balsamifera (Aubl)
Humiria balsamifera (Aubl), commonly known as “mirim”, is a plant of the Humiriaceae family, which consists of 39 species divided between eight genera: Duckesia, Endopleura, Humiria, Humiriastrum, Hylocara, Sacoglottis, Schistostemon, and Vantenea. This study aimed to characterize H. balsamifera extracts by LC-MS/MS and evaluate their antimicrobial potential through in vitro and in vivo assays. 
  • 930
  • 08 Nov 2021
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.
  • 926
  • 09 Aug 2023
Topic Review Peer Reviewed
Photoremovable Protecting Groups
Photoremovable protecting groups (PPGs) (also often called photocages in the literature) are used for temporary inactivation of biologically active substrates. By photoirradiation the PPG could be cleaved off and the biological activity could be restored on-demand, with a high spatiotemporal precision. The on-site liberation of the biologically active substrate could be exploited for studying dynamic biological processes or for designing targeted pharmacological interventions in vitro or in vivo. Several chemical scaffolds have been described and tested as PPGs, operating at different wavelengths. The scope of potential substrates is very broad, spanning from small molecules to proteins. In a wider context, PPGs could be used for the design of various light-responsive materials as well, for diverse applications. 
  • 923
  • 21 Oct 2022
Topic Review
Tellurophenes
Tellurophenes are the tellurium analogue of thiophenes and selenophenes.
  • 922
  • 12 Oct 2022
Topic Review
Catalytic Carbonylative Double Cyclization Reactions
Some examples of carbonylative double cyclization processes, which allow the one-step synthesis of complex molecular architectures from simple building blocks using the simplest and readily available C-1 unit (CO), are illustrated and discussed.
  • 922
  • 07 Jul 2023
Topic Review
Versatile Fluorine-Containing Building Blocks
The development of diversity-oriented synthesis based on fluorine-containing building blocks has been one of the hot research fields in fluorine chemistry. β-CF3-1,3-enynes, as one type of fluorine-containing building blocks, have attracted more attention due to their distinct reactivity. Numerous value-added trifluoromethylated or non-fluorinated compounds which have biologically relevant structural motifs, such as O-, N-, and S-heterocycles, carboncycles, fused polycycles, and multifunctionalized allenes were synthesized from these fluorine-containing building blocks.
  • 921
  • 30 Dec 2022
Topic Review
Potential Treatments for Viral Diseases
The COVID-19 pandemic, as well as the more general global increase in viral diseases, has led researchers to look to the plant kingdom as a potential source for antiviral compounds. Since ancient times, herbal medicines have been extensively applied in the treatment and prevention of various infectious diseases in different traditional systems. The purpose of this review is to highlight the potential antiviral activity of plant compounds as effective and reliable agents against viral infections, especially by viruses from the coronavirus group.
  • 902
  • 26 Jul 2021
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. 
  • 898
  • 12 Jul 2022
Topic Review
Synthesis of S-α-(Acyloxy)alkyl Xanthates
α-(Acyloxy)alkyl radicals of general structure 1 are key intermediates in the polymerization of vinyl esters 2, especially vinyl acetate (2, R = Me); however, their use in the synthesis of small molecules has remained underdeveloped.
  • 887
  • 01 Dec 2023
Topic Review
Sequential Reactions of α-Aminoalkynes with Carbonyls
Sequential reactions of aminoalkynes represent a powerful tool to easily assembly biologically important polyfunctionalized nitrogen heterocyclic scaffolds. Metal catalysis often plays a key role in terms of selectivity, efficiency, atom economy, and green chemistry of these sequential approaches.
  • 886
  • 26 Jun 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.
  • 880
  • 27 Aug 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. 
  • 874
  • 08 Jun 2022
Topic Review
Cannabineyed
The word cannabineyed refers to endocannabinoid system (ECS) physiology, dysregulation and modulation in the context of ocular and periocular tissues and structures. It derives by placing the word eye into the original one, cannabinoid. Specifically, the endocannabinoid system (ECS) is a complex regulatory system, highly conserved among vertebrates. It has been widely described in nearly all human tissues. In the eye, the ECS expression has been demonstrated both in the anterior and in the posterior segment. In this context, the ECS is believed to play a pivotal role in the modulation of the local inflammatory state as well as in the regulation of tissue repair and fibrosis, neo-angiogenesis, pain perception, intraocular pressure (IOP) control and neuroprotection.
  • 863
  • 12 Feb 2021
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. 
  • 859
  • 19 Sep 2022
Topic Review
Antibacterial Activities of 1,2,3-Triazolium Salts
1,2,3-Triazolium salts have demonstrated significant potential in the fields of medicine and agriculture, exhibiting exceptional antibacterial, antifungal, anticancer, and antileishmanial properties. Moreover, these salts can be utilized as additives or components to produce nano- and fiber-based materials with antibacterial properties. 
  • 857
  • 17 Jul 2023
Topic Review
Spiro-Flavonoids in Nature
The research collects 65 unique structures, including spiro-biflavonoids, spiro-triflavonoids, spiro-tetraflavonoids, spiro-flavostilbenoids, and scillascillin-type homoisoflavonoids. Scillascillin-type homoisoflavonoids comprise spiro[bicyclo[4.2.0]octane-7,3′-chromane]-1(6),2,4-trien-4′-one, while the other spiro-flavonoids contain either 2H,2′H-3,3′-spirobi[benzofuran]-2-one or 2′H,3H-2,3′-spirobi[benzofuran]-3-one in the core of their structures. Spiro-flavonoids have been described in more than 40 species of eight families, including Asparagaceae, Cistaceae, Cupressaceae, Fabaceae, Pentaphylacaceae, Pinaceae, Thymelaeaceae, and Vitaceae. The possible biosynthetic pathways for each group of spiro-flavonoids are summarized in detail. Anti-inflammatory and anticancer activities are the most important biological activities of spiro-flavonoids, both in vitro and in vivo.
  • 840
  • 25 Jul 2023
Topic Review
GlycoCDs
Glycocyclodextrins (glycoCDs) comprise a family of cyclodextrin-based multivalent glycoclusters in which unique 3D displays of glycoepitopes can be achieved. As a consequence of the conformational rigidity and dense functional display of cyclodextrins, and taking advantage of selective chemical functionalization and "click chemistry" schemes, the upper/lower distribution of glycoepitopes and the inward/outward hydrophobic/hydrophilic balance can be precisely tailored and tunned to achieve complex functional properties such as programed self-(dis)assembling or biological recognition processes.
  • 835
  • 11 Jan 2021
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.
  • 834
  • 17 Jan 2022
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. 
  • 834
  • 03 Nov 2022
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