scholarly journals Selenium-Containing Polysaccharides—Structural Diversity, Biosynthesis, Chemical Modifications and Biological Activity

2021 ◽  
Vol 11 (8) ◽  
pp. 3717
Author(s):  
Sandra Górska ◽  
Anna Maksymiuk ◽  
Jadwiga Turło
Keyword(s):  
Structural Diversity ◽  
Biological Properties ◽  
Immunomodulatory Activity ◽  
Selenium Compounds ◽  
Natural Origin ◽  
Inorganic Selenium ◽  
Sugar Ring ◽  
Immune Enhancement ◽  
Sugar Derivatives ◽  
Derivatives Of

Selenosugars are a group of sugar derivatives of great structural diversity (e.g., molar masses, selenium oxidation state, and selenium binding), obtained as a result of biosynthesis, chemical modification of natural compounds, or chemical synthesis. Seleno-monosaccharides and disaccharides are known to be non-toxic products of the natural metabolism of selenium compounds in mammals. In the case of the selenium-containing polysaccharides of natural origin, their formation is also postulated as a form of detoxification of excess selenium in microorganisms, mushroom, and plants. The valency of selenium in selenium-containing polysaccharides can be: 0 (encapsulated nano-selenium), IV (selenites of polysaccharides), or II (selenoglycosides or selenium built into the sugar ring to replace oxygen). The great interest in Se-polysaccharides results from the expected synergy between selenium and polysaccharides. Several plant- and mushroom-derived polysaccharides are potent macromolecules with antitumor, immunomodulatory, antioxidant, and other biological properties. Selenium, a trace element of fundamental importance to human health, has been shown to possess several analogous functions. The mechanism by which selenium exerts anticancer and immunomodulatory activity differs from that of polysaccharide fractions, but a similar pharmacological effect suggests a possible synergy of these two agents. Various functions of Se-polysaccharides have been explored, including antitumor, immune-enhancement, antioxidant, antidiabetic, anti-inflammatory, hepatoprotective, and neuroprotective activities. Due to being non-toxic or much less toxic than inorganic selenium compounds, Se-polysaccharides are potential dietary supplements that could be used, e.g., in chemoprevention.

Bio-organometallic Peptide Conjugates: Recent Advances in Their Synthesis and Prospects for Biomedical Application

2020 ◽  
Vol 24 (21) ◽  
pp. 2508-2523
Author(s):  
Johana Gómez ◽  
Diego Sierra ◽  
Constanza Cárdenas ◽  
Fanny Guzmán
Keyword(s):  
Amino Acids ◽  
Biomedical Application ◽  
Structural Diversity ◽  
Biological Properties ◽  
Therapeutic Agents ◽  
Organometallic Complexes ◽  
Chemical Behavior ◽  
Metal Compounds ◽  
Bioorganometallic Chemistry ◽  
Pharmacological Control

One area of organometallic chemistry that has attracted great interest in recent years is the syntheses, characterization and study of organometallic complexes conjugated to biomolecules with different steric and electronic properties as potential therapeutic agents against cancer and malaria, as antibiotics and as radiopharmaceuticals. This minireview focuses on the unique structural diversity that has recently been discovered in α- amino acids and the reactions of metallocene complexes with peptides having different chemical behavior and potential medical applications. Replacing α-amino acids with metallocene fragments is an effective way of selectively influencing the physicochemical, structural, electrochemical and biological properties of the peptides. Consequently, research in the field of bioorganometallic chemistry offers the opportunity to develop bioactive metal compounds as an innovative and promising approach in the search for pharmacological control of different diseases.

Effect of Substituents on Photochemical and Biological Properties of 13,15-N-Cycloimide Derivatives of Chlorin p6

2005 ◽  
Vol 31 (5) ◽  
pp. 482-494 ◽  
Author(s):  
A. I. Nazarova ◽  
A. V. Feofanov ◽  
T. A. Karmakova ◽  
G. V. Sharonov ◽  
A. D. Plyutinskaya ◽  
...  
Keyword(s):  
Biological Properties ◽  
Effect Of Substituents ◽  
Derivatives Of ◽  
Chlorin P6

Structural Diversity of Nanoscale Zirconium Porphyrin MOFs and Their Photoactivities and Biological Performances

2021 ◽  
Author(s):  
Zhigang Xie ◽  
Lei Wang ◽  
YiTe Li ◽  
Junli Zhou
Keyword(s):  
Photodynamic Therapy ◽  
Structural Parameters ◽  
Structural Diversity ◽  
Biological Properties ◽  
Delivery Systems

Photoactive MOFs-based delivery systems are highly attractive for photodynamic therapy (PDT), but the fundamental interplay among structural parameters and photoactivity and biological properties of those MOFs remains unclear. Herein, porphyrinic...

STUDY OF THE BIOLOGICAL PROPERTIES OF SEMI- AND THIOSEMICARBAZONES OF CARBONYL DERIVATIVES OF 4-BUTANOLIDES

2021 ◽  
Vol 55 (2 (255)) ◽  
pp. 103-111
Author(s):  
Tariel V. Ghochikyan ◽  
Armen S. Galstyan ◽  
Hrachik M. Stepanyan ◽  
Irina G. Korpakova ◽  
Alexander S. Kinzirsky
Keyword(s):  
Antitumor Activity ◽  
Green Alga ◽  
Biological Properties ◽  
Lymphocytic Leukemia ◽  
Thiazole Ring ◽  
Lewis Lung ◽  
Ehrlich's Ascites Tumor ◽  
Carbonyl Derivatives ◽  
Derivatives Of ◽  
Test Objects

Based on carbonyl derivatives of 4-substituted-4-butanolides, the appropriate semi- and thiosemicarbazones have been synthesized. It has been found that some representatives of thiosemicarbazones have pronounced algicidal activity against filamentous green alga Cladophora and blue-green alga (cyanobacterium) Synechocystis and some of the semi- and thiosemicarbazones exhibit moderate antitumor activity. The assessment of the antitumor activity of the compounds was carried out using strains of syngeneic and allogeneic tumor systems as test-objects: lymphocytic leukemia P-388, Lewis lung carcinoma, B16 melanoma and Ehrlich’s ascites tumor. It has also been established that some representatives of thiosemi­carbazones exhibit antimutagenic properties. It has been reliably proven that with the formation of a thiazole ring, all properties disappear and a new property in the series of thiazololactones is revealed – antibacterial․

Chemical principles of Boophone, Nerine, Crossyne, Clivia, Cryptostephanus, Haemanthus and Scadoxus of the South African Amaryllidaceae and their biological properties

Planta Medica ◽  
2021 ◽  
Author(s):  
Jerald Nair ◽  
Johannes Van Staden
Keyword(s):  
South African ◽  
Biological Activities ◽  
Structural Diversity ◽  
Biological Properties ◽  
Isoquinoline Alkaloid ◽  
Flowering Plant ◽  
New Information ◽  
Regulatory Effects ◽  
Plant Families ◽  
Antioxidant Effects

The Amaryllidaceae features prominently amongst bulbous flowering plant families. Accommodating about a third of its species, South Africa affords a sound basis for Amaryllidaceae plant research. Boophone, Nerine, Crossyne, Clivia, Cryptostephanus, Haemanthus and Scadoxus have been well-represented in such endeavors. The account herein summarizes the studies undertaken between 2013-2020 on these genera in regards to their chemical and biological characteristics. A total of 136 compounds comprising 63 alkaloids and 73 non-alkaloid entities were described during this period from eighteen members of the title genera. The alkaloids were reflective of the structural diversity found in eight isoquinoline alkaloid groups of the Amaryllidaceae. Of these, the crinane (29 compounds), lycorane and homolycorine (11 compounds each) groups were the most-represented. The non-alkaloid substances were embracive of the same number of unrelated groups including, acids, phenolics, flavonoids and triterpenoids. A wide variety of assays were engaged to ascertain the biological activities of the isolated compounds, notably in regards to cancer and motorneuron-related diseases. There were also attempts made to determine the antimicrobial, anti-inflammatory and antioxidant effects of some of the substances. New information has also emerged on the herbicidal, insecticidal and plant growth regulatory effects of selected alkaloid principles. Coupled to the biological screening measures were in instances probes made to establish the molecular basis to some of the activities, particularly in relation to cancer and Parkinsonʹs disease.

scholarly journals Detergent Plants of Northern Thailand: Potential Sources of Natural Saponins

2018 ◽  
Author(s):  
Jiratchaya Wisetkomolmat ◽  
Pongsakorn Suppakittpaisarn ◽  
Sarana Rose Sommano
Keyword(s):  
Plant Species ◽  
Physiological Mechanism ◽  
Structural Diversity ◽  
Bioactive Compound ◽  
Biological Properties ◽  
Industrial Applications ◽  
Natural Forests ◽  
Northern Thailand ◽  
Foaming Agents ◽  
Plant Environment

The natural forests of Northern Thailand are the mother source of many utilisable natural products because of their diverse flora and fauna. Among many plant species found within Northern Thai forests, detergent plants are known for its distinctive cleansing properties. Several local species of detergent plants in Thailand are traditionally used by the locals and indigenous people. However, these plants may become extinct because their habitats have been replaced by industrial agriculture, and their uses have been replaced by chemically synthesised detergents. Researchers need to study and communicate the biology, phytochemistry, and the importance of these plants to conserve natural biodiversity of Northern Thailand. Of many utilisable detergent phytochemicals, natural saponins are known as bio-surfactant and foaming agents. Their physiochemical and biological properties feature structural diversity, which leads to many industrial applications.  In this review, we explained the term “detergent” from the physiological mechanism perspective and the detergent effects of saponin.  We also compiled a list of Thai local plants with cleansing properties focusing on the saponin-containing plants. Future studies should investigate information relative to plant environment, ethnobotanical data and bioactive compound content of these plants. The knowledge acquired from this study will promote the maintenance of the local biodiversity and the conservation of the detergent plant species found in Thailand.

scholarly journals RECENTES AVANÇOS NA FUNCIONALIZAÇÃO SELETIVA DE QUINOLINAS

Química Nova ◽  
2021 ◽  
Author(s):  
Dartagnan Ferreira ◽  
Valter Murie ◽  
Thiago Santos ◽  
Paulo Vieira ◽  
Giuliano Clososki
Keyword(s):  
Wide Spectrum ◽  
Structural Diversity ◽  
Biological Properties ◽  
Biologically Active ◽  
Chemical Transformations ◽  
Heterocyclic Molecules ◽  
Point Of Interest ◽  
Selective Functionalization ◽  
Biological Interest ◽  
Approved Drugs

RECENT ADVANCES IN SELECTIVE FUNCTIONALIZATION OF QUINOLINES. Heterocyclic compounds form an important and extensive group of organic substances. Among nitrogenous heterocyclic molecules, quinolines stand out for exhibiting attractive chemical and biological properties. These substances can be used as ligands, sensors, luminescent and agrochemical materials. In addition, quinoline-containing compounds can exhibit a wide spectrum of pharmacological properties, allowing their use in several approved drugs nowadays. Due to its importance, the synthesis of molecules containing this nucleus becomes a point of interest for synthetic chemists. In this way, several methodologies have been recently developed to prepare quinoline derivatives with high structural diversity. Such chemical transformations allow the chemical modification of these rings with high selectivity and tolerance to diverse functional groups and these properties have been conveniently used in the preparation of biologically active molecules containing this unit. Herein, we present a review of the main methodologies employed in the selective functionalization of quinolines in the last twenty years. In this context, a brief introduction addressing general synthetic and medicinal aspects related to the functionalization positions of the quinoline ring is presented. Several methodologies used in the functionalization of this moiety are discussed, as well relevant synthetic applications, both in the preparation and functionalization of substances of biological interest.

Synthesis of new cyclopeptide analogues of the miuraenamides

2021 ◽  
Vol 18 ◽  
Author(s):  
Sarah Kappler ◽  
Andreas Siebert ◽  
Uli Kazmaier
Keyword(s):  
Natural Products ◽  
Biological Properties ◽  
Amide Bond ◽  
Side Chain ◽  
Aromatic Side Chain ◽  
Highly Active ◽  
C Terminus ◽  
Terminal Amino ◽  
High Cytotoxicity ◽  
Derivatives Of

Introduction: Miuraenamides belong to marine natural compounds with interesting biological properties. Materials and Methods: They initiate polymerization of monomeric actin and therefore show high cytotoxicity by influencing the cytoskeleton. New derivatives of the miuraenamides have been synthesized containing a N-methylated amide bond instead of the more easily hydrolysable ester in the natural products. Results: Incorporation of an aromatic side chain onto the C-terminal amino acid of the tripeptide fragment also led to highly active new miuraenamides. Conclusion: We could show that the ester bond of the natural product miuraenamide can be replaced by an N-methyl amide. The yields in the cyclization step are high and generally much better that with the corresponding esters. On the other hand, the biological activity of the new amide analogs are lower compared to the natural products, but the activity can significantly be increased by incorporation of a p-nitrophenyl group at the C-terminus of the peptide fragment.

Sign in / Sign up

Export Citation Format

Share Document