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Topic Review
Homogeneous and Heterogeneous Copper Catalyst
The applications of Copper-based nanoparticles have received great attention due to the earth-abundant, low toxicity and inexpensive. Due to these characteristics, copper nanoparticles have generated a great deal of interest especially in the field of catalysis. Traditional Ullmann-type couplings suffer from limited substrate scopes and harsh reaction conditions. The introduction of a new copper-based catalyst over the past two decades has totally changed this situation as it enables the reaction promoted in mild condition. The reaction scope has also been greatly expanded, rendering this copper-based cross-coupling attractive for both academia and industry. Transition metal-catalyzed chemical transformation of organic electrophiles and organometallic reagents belong to the most important cross-coupling reaction in organic synthesis. The biaryl ether division is not only popular in natural products and synthetic pharmaceuticals but also widely found in many pesticides, polymers, and ligands. Copper catalyst has received great attention owing to the low toxicity and low cost. The introduction of homogeneous copper catalysts with the presence of bidentate ligands and also heterogeneous copper catalyst over the past two decades has totally changed this situation as these ligands enable the reaction promoted in mild condition. The reaction scope has also been greatly expanded, rendering this copper-based cross-coupling attractive for both academia and industry. This review had been summarized recently advance homogeneous and heterogeneous copper catalyst in Ullmann reaction and its application and natural product and pharmaceutical industry.
  • 2.7K
  • 09 Oct 2020
Topic Review
Ascorbic Acid-Induced Reactions
Ascorbic acid is the most well-known vitamin found in different types of food. It has tremendous medical applications in several different fields such as in pharmaceuticals, cosmetics, and in organic synthesis. Ascorbic acid can be used as a substrate or mediator in organic synthesis. In this review, we report ascorbic acid-catalyzed reactions in organic synthesis. Several examples are included in this review to demonstrate that ascorbic acid is a versatile catalyst for the synthesis of diverse organic compounds. Reactions catalyzed by ascorbic acid are performed in organic or aqueous media. The readily available and easy handling features of ascorbic acid make these procedures highly fascinating.
  • 2.7K
  • 25 Nov 2020
Topic Review
Dipole Moment
Synthesis, biological activity and structure-activity relationships of diverse compounds are described. The relationships between dipole moment and biological activities are discussed. Despite the progress of interdisciplinary science, the use of dipole moment values of organic compounds to understand their potent medicinal activities in various diseases remains unexplored.
  • 2.5K
  • 25 Nov 2020
Topic Review
Five-Membered Heterocyclic Compounds
Heterocyclic compounds are a class of compounds of natural origin with favorable properties and hence have major pharmaceutical significance. They have an exceptional adroitness favoring their use as diverse smart biomimetics, in addition to possessing an active pharmacophore in a complex structure. This has made them an indispensable motif in the drug discovery field. Heterocyclic compounds are usually classified according to the ring size, type, and the number of heteroatoms present in the ring.
  • 2.4K
  • 16 Aug 2022
Topic Review
Milk Fat Globule Membrane (MFGM)
Milk fat globule membrane (MFGM) is an important component of milk lipids that showed several biological properties (such as anticarcinogenic, antimicrobial, anti-inflammatory, and anticholesterolemic activities). In this review we analyse the latest results obtained from comparative proteomic studies regarding the variations and the similarities of MFGM proteome across species and lactation stages. Infant formula supplementation with MFGM represents an interesting opportunity to implement the bioactive properties exerted by MFGM, in order to narrow the gap between human breast milk and infant formula. 
  • 2.4K
  • 27 Sep 2020
Topic Review
Triptycene Synthesis and Derivatization
Since the discovery of triptycenes, great progress has been made regarding their synthetic methodology and the understanding of inter- and intramolecular interactions that involve triptycenes. Several new synthetic approaches have been developed in the last few years, and progress has been made in the context of sterically congested triptycenes and regioselective synthesis of various derivatives.
  • 2.2K
  • 06 Jan 2022
Topic Review
Beta-Carotene
β-Carotene is an organic, strongly coloured red-orange pigment abundant in fungi, plants, and fruits. It is a member of the carotenes, which are terpenoids (isoprenoids), synthesized biochemically from eight isoprene units and thus having 40 carbons. Among the carotenes, β-carotene is distinguished by having beta-rings at both ends of the molecule. β-Carotene is biosynthesized from geranylgeranyl pyrophosphate. In some Mucoralean fungi, β-Carotene is a precursor to the synthesis of trisporic acid. β-Carotene is the most common form of carotene in plants. When used as a food coloring, it has the E number E160a.:119 The structure was deduced by Karrer et al. in 1930. In nature, β-carotene is a precursor (inactive form) to vitamin A via the action of beta-carotene 15,15'-monooxygenase. Isolation of β-carotene from fruits abundant in carotenoids is commonly done using column chromatography. It can also be extracted from the beta-carotene rich algae, Dunaliella salina. The separation of β-carotene from the mixture of other carotenoids is based on the polarity of a compound. β-Carotene is a non-polar compound, so it is separated with a non-polar solvent such as hexane. Being highly conjugated, it is deeply colored, and as a hydrocarbon lacking functional groups, it is very lipophilic.
  • 2.2K
  • 16 Nov 2022
Topic Review
Thiosugars of Biological Significance
Thiosugars are important compounds because of their structural complexity and crucial biological activities. Therefore, a series of methods are developed for their synthesis using new methods. Unlike, oxygen sugars, thiosugars are more stable and therefore, much scope exists to alter their structures by chemical manipulations. Notably, thiosugars can act as glycosyl donors as well as acceptors.  Many functionalized thiosugars occur naturally and are potential targets for therapeutics. Synthesis of thiosugars following convergent route is a challenge.  Over the years, scientists have explored thiosugars through numerous green and sustainable methods. These studies are highly significant and timely since it opens the door towards carbohydrate-based drugs.
  • 2.0K
  • 25 Nov 2020
Topic Review
Phospholipids
Phospholipids are unique and versatile molecules. They are of natural occurrence and the main components in cellular membranes. Arranged as a lipid bilayer, phospholipids play a significant role in the structure and functionality of biological membranes. They are amphiphilic and consist of a hydrophilic headgroup and a lipophilic/hydrophobic tail.
  • 2.0K
  • 04 Feb 2021
Topic Review
DPPH· Stable Free Radical
DPPH· is 2,2-diphenyl-1-(2,4,6-trinitrophenyl)hydrazyl stable free radical. It was discovered in 1922.
  • 1.9K
  • 24 Feb 2021
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