Carolina C. Martins

Bio: Carolina C. Martins is an academic researcher from Universidade Federal de Pelotas. The author has contributed to research in topics: Nanocapsules & Transdermal. The author has an hindex of 1, co-authored 5 publications receiving 3 citations.

Synthesis of 2-Organylchalcogenopheno[2,3-b]pyridines from Elemental Chalcogen and NaBH4 /PEG-400 as a Reducing System: Antioxidant and Antinociceptive Properties.

Abstract: An alternative method to prepare 2-organylchalcogenopheno[2,3-b]pyridines was developed by the insertion of chalcogen species (selenium, sulfur or tellurium), generated in situ, into 2-chloro-3-(organylethynyl)pyridines by using the NaBH4 /PEG-400 reducing system, followed by an intramolecular cyclization. It was possible to obtain a series of compounds with up to 93 % yield in short reaction times. Among the synthesized products, 2-organyltelluropheno[2,3-b]pyridines have not been described in the literature so far. Moreover, the compounds 2-phenylthieno[2,3-b]pyridine (3 b) and 2-phenyltelluropheno[2,3-b]pyridine (3 c) exhibited significant antioxidant potential in different in vitro assays. Further studies demonstrated that compound 3 b exerted an antinociceptive effect in acute inflammatory and non-inflammatory pain models, thus indicating the involvement of the central and peripheral nervous systems on its pharmacological action. More specifically, our results suggest that the intrinsic antioxidant property of compound 3 b might contribute to attenuating the nociception and inflammatory process on local injury induced by complete Freund's adjuvant (CFA).

Natural Antioxidants from Plant Extracts in Skincare Cosmetics: Recent Applications, Challenges and Perspectives

Abstract: In recent years, interest in the health effects of natural antioxidants has increased due to their safety and applicability in cosmetic formulation. Nevertheless, efficacy of natural antioxidants in vivo is less documented than their prooxidant properties in vivo. Plant extracts rich in vitamins, flavonoids, and phenolic compounds can induce oxidative damage by reacting with various biomolecules while also providing antioxidant properties. Because the biological activities of natural antioxidants differ, their effectiveness for slowing the aging process remains unclear. This review article focuses on the use of natural antioxidants in skincare and the possible mechanisms underlying their desired effect, along with recent applications in skincare formulation and their limitations.

Decoding Directing Groups and Their Pivotal Role in C−H Activation

Abstract: Synthetic organic chemistry has witnessed a plethora of functionalization and defunctionalization strategies In this regard, C-H functionalization has been at the forefront due to the multifarious applications in the development of simple to complex molecular architectures and holds a brilliant prospect in drug development and discovery Despite been explored tremendously by chemists, this functionalization strategy still enjoys the employment of novel metal catalysts as well metal-free organic ligands Moreover, the switch to photo- and electrochemistry has widened our understanding of the alternative pathways via which a reaction can proceed and these strategies have garnered prominence when applied to C-H activation Synthetic chemists have been foraging for new directing groups and templates for the selective activation of C-H bonds from a myriad of carbon-hydrogen bonds in aromatic as well as aliphatic systems As a matter of fact, by varying the templates and directing groups, scientists found the answer to the challenge of distal C-H bond activation which remained an obstacle for a very long time These templates have been frequently harnessed for selectively activating C-H bonds of natural products, drugs, and macromolecules decorated with multiple C-H bonds This itself was a challenge before the commencement of this field as functionalization of a site other than the targeted site could modify and hamper the biological activity of the pharmacophore Total synthesis and pharmacophore development often faces the difficulty of superfluous reaction steps towards selective functionalization This obstacle has been solved by late-stage functionalization simply by harnessing C-H bond activation Moreover, green chemistry and metal-free reaction conditions have seen light in the past few decades due to the rising concern about environmental issues Therefore, metal-free catalysts or the usage of non-toxic metals have been recently showcased in a number of elegant works Also, research groups across the world are developing rational strategies for directing group free or non-directed protocols that are just guided by ligands This review encapsulates the research works pertinent to C-H bond activation and discusses the science devoted to it at the fundamental level This review gives the readers a broad understanding of how these strategies work, the execution of various metal catalysts, and directing groups This not only helps a budding scientist towards the commencement of his/her research but also helps a matured mind searching out for selective functionalization A detailed picture of this field and its progress with time has been portrayed in lucid scientific language with a motive to inculcate and educate scientific minds about this beautiful strategy with an overview of the most relevant and significant works of this era The unique trait of this review is the detailed description and classification of various directing groups and their utility over a wide substrate scope This allows an experimental chemist to understand the applicability of this domain and employ it over any targeted substrate

Recent Advances in the Synthesis of Selenophenes and Their Derivatives.

Abstract: The selenophene derivatives are an important class of selenium-based heterocyclics. These compounds play an important role in prospecting new drugs, as well as in the development of new light-emitting materials. During the last years, several methods have been emerging to access the selenophene scaffold, employing a diversity of cyclization-based synthetic strategies, involving specific reaction partners and particularities. This review presents a comprehensive discussion on the recent advances in the synthesis of selenophene-based compounds, starting from different precursors, highlighting the main differences, the advantages, and limitations among them.

Punicic Acid and Its Role in the Prevention of Neurological Disorders: A Review

Abstract: Millions of people worldwide are affected by neurodegenerative diseases (NDs). NDs are characterized by progressive damage and death of nerve cells accompanied by high levels of inflammatory biomarkers and oxidative stress conditions. Punicic acid, the main bioactive component of pomegranate (Punica granatum) seed oil, is an omega-5 isomer of conjugated α-linoleic acid that has shown strong anti-oxidative and anti-inflammatory effects that contributes towards its positive effect against a wide arrange of diseases. Punicic acid decreases oxidative damage and inflammation by increasing the expression of peroxisome proliferator-activated receptors. In addition, it can reduce beta-amyloid deposits formation and tau hyperphosphorylation by increasing the expression of GLUT4 protein and the inhibition of calpain hyperactivation. Microencapsulated pomegranate, with high levels of punicic acid, increases antioxidant PON1 activity in HDL. Likewise, encapsulated pomegranate formulations with high levels of punicic acid have shown an increase in the antioxidant PON1 activity in HDL. Because of the limited brain permeability of punicic acid, diverse delivery formulations have been developed to enhance the biological activity of punicic acid in the brain, diminishing neurological disorders symptoms. Punicic acid is an important nutraceutical compound in the prevention and treatment of neurodegenerative diseases such as Alzheimer’s, Parkinson’s, and Huntington’s disease.