scholarly journals Solid-Phase Selenium-Catalyzed Selective Allylic Chlorination of Polyprenoids: Facile Syntheses of Biologically Active Terpenoids.

ChemInform ◽  
2006 ◽  
Vol 37 (49) ◽  
Author(s):  
Alejandro F. Barrero ◽  
Jose F. Quilez del Moral ◽  
M. Mar Herrador ◽  
Manuel Cortes ◽  
Pilar Arteaga ◽  
...  
Keyword(s):  
Solid Phase ◽  
Biologically Active

Synthetic Routes for 1,4-disubstituted 1,2,3-triazoles: A Review

2019 ◽  
Vol 23 (8) ◽  
pp. 860-900 ◽  
Author(s):  
Chander P. Kaushik ◽  
Jyoti Sangwan ◽  
Raj Luxmi ◽  
Krishan Kumar ◽  
Ashima Pahwa
Keyword(s):  
Solid Phase ◽  
Click Reaction ◽  
Biological Activities ◽  
Triazole Ring ◽  
Copper Catalysts ◽  
Biologically Active ◽  
Pharmaceutical Chemistry ◽  
Biological Targets ◽  
Synthetic Routes ◽  
High Yields

N-Heterocyclic compounds like 1,2,3-triazoles serve as a key scaffolds among organic compounds having diverse applications in the field of drug discovery, bioconjugation, material science, liquid crystals, pharmaceutical chemistry and solid phase organic synthesis. Various drugs containing 1,2,3-triazole ring which are commonly available in market includes Rufinamide, Cefatrizine, Tazobactam etc., Stability to acidic/basic hydrolysis along with significant dipole moment support triazole moiety for appreciable participation in hydrogen bonding and dipole-dipole interactions with biological targets. Huisgen 1,3-dipolar azide-alkyne cycloaddition culminate into a mixture of 1,4 and 1,5- disubstituted 1,2,3-triazoles. In 2001, Sharpless and Meldal came across with a copper(I) catalyzed regioselective synthesis of 1,4-disubstituted 1,2,3-triazoles by cycloaddition between azides and terminal alkynes. This azide-alkyne cycloaddition has been labelled as a one of the important key click reaction. Click synthesis describes chemical reactions that are simple to perform, gives high selectivity, wide in scope, fast reaction rate and high yields. Click reactions are not single specific reaction, but serve as a pathway for construction of simple to complex molecules from a variety of starting materials. In the last few decades, 1,2,3-triazoles attracted attention of researchers all over the world because of their broad spectrum of biological activities. Keeping in view the biological importance of 1,2,3-triazole, in this review we focus on the various synthetic routes for the syntheisis of 1,4-disubstituted 1,2,3-triazoles. This review involves various synthetic protocols which involves copper and non-copper catalysts, different solvents as well as substrates. It will boost synthetic chemists to explore new pathway for the development of newer biologically active 1,2,3-triazoles.

The importance of linkers in the structure of PSMA ligands

2021 ◽  
Vol 28 ◽  
Author(s):  
Anastasia A. Uspenskaya ◽  
Ekaterina A. Nimenko ◽  
Aleksei E. Machulkin ◽  
Elena K. Beloglazkina ◽  
Alexander G. Majouga
Keyword(s):  
Prostate Cancer ◽  
Solid Phase ◽  
Biologically Active ◽  
Modern World ◽  
Synthesis Methods ◽  
Amino Acid Residues ◽  
Ongoing Research ◽  
Phase Synthesis ◽  
Diagnose Prostate Cancer ◽  
Positive Effect

: Cancer is one of the leading social problems of the modern world. Today prostate cancer is the second leading cause of cancer deaths among men. Targeted drug delivery is widely used to treat and diagnose prostate cancer. Conjugates selectively binding to prostate specific membrane antigen based on urea ligands are being actively developed against this disease. The linker has a significant influence on the biological activity of such conjugates. The linker performs a large number of functions, and its modification is one of the key methods of creating the best pharmacological profile. This review aims to discuss and analyze the main approaches to the method of introduction and synthesis of linkers for this type of conjugates without a description of the influence of biologically active molecules, as well as to establish the key modification methods that have a significant role on the structure-activity relationship. For this purpose, a review of the current scientific literature was performed, both for the conjugates under development and for those already undergoing clinical trials. It was found that the optimal structure is a linker containing an aliphatic fragment near the vector-molecule (n(CH2) = 3-6), followed by a polypeptide chain consisting of 2 to 4 amino acid residues. The presence of a Phe-Phe dipeptide chain or the introduction of negatively charged groups also has a positive effect. Ongoing research in this field helps to establish the accurate effect of each linker fragment, and the development of solid-phase synthesis methods makes it much easier to achieve this goal.

Analysis of biologically active oxyprenylated phenylpropanoids in Tea tree oil using selective solid-phase extraction with UHPLC-PDA detection

2018 ◽  
Vol 154 ◽  
pp. 174-179 ◽  
Author(s):  
Luca Scotti ◽  
Salvatore Genovese ◽  
Tonino Bucciarelli ◽  
Filippo Martini ◽  
Francesco Epifano ◽  
...  
Keyword(s):  
Solid Phase Extraction ◽  
Solid Phase ◽  
Biologically Active ◽  
Phase Extraction ◽  
Tea Tree Oil ◽  
Tea Tree

scholarly journals Magnetically responsive materials for solid phase extraction

2019 ◽  
Vol 6 (1) ◽  
pp. 15-20 ◽  
Author(s):  
Ivo Safarik ◽  
Jitka Prochazkova ◽  
Eva Baldikova ◽  
Kristyna Pospiskova
Keyword(s):  
Solid Phase Extraction ◽  
Limit Of Detection ◽  
Solid Phase ◽  
Analytical Techniques ◽  
Magnetic Solid Phase Extraction ◽  
Short Review ◽  
Biologically Active ◽  
Phase Extraction ◽  
Responsive Materials ◽  
Magnetic Solid

Magnetically responsive materials have found many important applications in analytical chemistry. In this short review the basic information about Magnetic solid phase extraction and Magnetic textile solid phase extraction is given. These analytical techniques enable to preconcentrate target biologically active compounds or pollutants from water samples. Both procedures enable to lower the limit of detection using conventional analytical procedures.

scholarly journals Studies of the Variability of Polyphenols and Carotenoids in Different Methods Fermented Organic Leaves of Willowherb (Chamerion angustifolium (L.) Holub)

2020 ◽  
Vol 10 (15) ◽  
pp. 5254
Author(s):  
Marius Lasinskas ◽  
Elvyra Jariene ◽  
Nijole Vaitkeviciene ◽  
Jurgita Kulaitiene ◽  
Katarzyna Najman ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
High Performance ◽  
Solid Phase ◽  
Antioxidant Properties ◽  
Hierarchical Cluster ◽  
Organic Production ◽  
Biologically Active ◽  
Total Phenolic ◽  
Total Carotenoids ◽  
Chamerion Angustifolium

The demand for organic production is increasing worldwide. The willowherb, grown in an organic way, contributes greatly to the idea of a healthier society and clean land. Willowherb is widespread in the world and has high polyphenols, carotenoids, and antioxidant properties. The purpose of this work was to investigate the influence of solid-phase fermentation (SPF) under different conditions on the variation of polyphenols and carotenoids in the organic leaves of willowherb. The leaves were fermented for different periods of time: 24, 48, and 72 h; and in aerobic and anaerobic conditions. The evaluation of polyphenols and carotenoids was completed using high-performance liquid chromatography (HPLC), and antioxidant activity was measured with spectrophotometric method. Hierarchical cluster analysis was used to describe differences in biologically active compounds between willowherb samples. The experiment showed that the highest quantities of total phenolic acids and flavonoids were determined after 24 h under aerobic SPF, but the amountof total carotenoids was higher after 72 h anaerobic SPF, compared to control. Not-fermented willowherb leaves had a lower antioxidant activity. compared to fermented leaves. In conclusion, SPF can be used to change polyphenol and carotenoid quantities in organic leaves of willowherb.

Streptomyces halstedii K122 produces the antifungal compounds bafilomycin B1 and C1

2000 ◽  
Vol 46 (8) ◽  
pp. 753-758 ◽  
Author(s):  
Emma Frändberg ◽  
Carl Petersson ◽  
Lennart N Lundgren ◽  
Johan Schnürer
Keyword(s):  
Aspergillus Fumigatus ◽  
Amphotericin B ◽  
Solid Phase ◽  
Hyphal Growth ◽  
Biologically Active ◽  
Antifungal Compounds ◽  
Penicillium Roqueforti ◽  
Mucor Hiemalis ◽  
Nikkomycin Z ◽  
Streptomyces Halstedii

Streptomyces halstedii K122 was previously found to produce antifungal compounds on solid substrates that inhibit radial growth of fungi among Ascomycetes, Basidiomycetes, Deuteromycetes, Oomycetes, and Zygomycetes, and strongly affected hyphal branching and morphology. During growth of S. halstedii K122 in submerged culture, no antifungal activity could be detected. However, cultivation of S. halstedii in thin (1 mm) liquid substrate layers in large surface-area tissue culture flasks caused intense growth and sporulation of S. halstedii K122, and the biologically active compounds could be extracted from the mycelium with methanol. Antifungal compounds were purified using C18 solid phase extraction and silica gel column chromatography, and identified as bafilomycins B1 and C1, using 2D NMR and FAB MS. Production of bafilomycins, which are specific inhibitors of vacuolar ATPases, has not been reported from S. halstedii previously. Minimum inhibitory concentrations (MIC) of bafilomycins B1 and C1, amphotericin B, and nikkomycin Z were determined at pH 5.5 and 7.0 for the target fungi Aspergillus fumigatus, Mucor hiemalis, Penicillium roqueforti, and Paecilomyces variotii. Penicillium roqueforti was the most sensitive species to all the compounds investigated. The MIC values for amphotericin B were 0.5-4 µg·mL-1 for the fungi tested, and pH did not affect the toxicity. The MIC values for nikkomycin Z ranged from <0.5 µg·mL-1 for Mucor hiemalis to >500 µg·mL-1 for Aspergillus fumigatus, and pH had no influence on toxicity. Bafilomycins B1 and C1 were equally active against the fungal species tested, with MIC values in the range of <0.5-64 µg·mL-1. All fungi were more sensitive to both bafilomycin B1 and C1 at pH 7.0 than at pH 5.5.Key words: antifungal, bafilomycin, MIC, hyphal growth, Streptomyces halstedii.

scholarly journals Total Solid-Phase Synthesis of Biologically Active Drosophila Insulin-Like Peptide 2 (DILP2)

2017 ◽  
Vol 70 (2) ◽  
pp. 208 ◽  
Author(s):  
Feng Lin ◽  
Mohammed Akhter Hossain ◽  
Stephanie Post ◽  
Galina Karashchuk ◽  
Marc Tatar ◽  
...  
Keyword(s):  
Solid Phase ◽  
Cell Signalling ◽  
Fruit Fly ◽  
Total Solid ◽  
Biologically Active ◽  
Loss Of Function ◽  
Phase Synthesis ◽  
Function Relationship ◽  
G Protein Coupled ◽  
Synthesis Protocol

In the fruit fly Drosophila melanogaster, there are eight insulin-like peptides (DILPs) with DILPs 1–7 interacting with a sole insulin-like receptor tyrosine kinase (DInR) while DILP8 interacts with a single G protein-coupled receptor (GPCR), Lgr3. Loss-of-function dilp mutation studies show that the neuropeptide DILP2 has a key role in carbohydrate and lipid metabolism as well as longevity and reproduction. A better understanding of the processes whereby DILP2 mediates its specific actions is required. Consequently we undertook to prepare DILP2 as part of a larger, detailed structure–function relationship study. Use of our well established insulin-like peptide synthesis protocol that entails separate solid-phase assembly of each of the A- and B-chains with selective cysteine S-protection followed by sequential S-deprotection and simultaneous disulfide bond formation produced DILP2 in good overall yield and high purity. The synthetic DILP2 was shown to induce significant DInR phosphorylation and downstream signalling, with it being more potent than human insulin. This peptide will be a valuable tool to provide further insights into its binding to the insulin receptor, the subsequent cell signalling, and role in insect metabolism.

scholarly journals THE MAIN CONCEPTS OF SYNTHESIS OF PEPTIDES AS A NEW GENERATION OF BIOLOGICALLY ACTIVE DRUGS

2021 ◽  
Vol 58 ◽  
pp. 62-65
Author(s):  
Mikhail A. Polianskii ◽  
◽  
Anatoly I. Ginak ◽  
Keyword(s):  
Large Scale ◽  
Solid Phase ◽  
Biologically Active ◽  
Solid Polymer ◽  
Environmental Standards ◽  
Polymer Carrier ◽  
Phase Synthesis ◽  
Biological Targets ◽  
Living Organisms ◽  
New Generation

Currently, peptide-based drugs are increasingly replacing dosage forms which have been widely used for many years due to their affinity for living organisms and greater selectivity to biological targets, which lead to a growing demand. To meet that demand, a method using a solid polymer carrier (solid-phase synthesis), which has no alternative for fast and large-scale synthesis, is used. Nevertheless, work on its improvement is carried out non-stop, not only to optimize the chemical process, but also to bring the process to compliance with environmental standards dictated by modern concepts of green chemistry

scholarly journals The Analysis of Process of Crushing in the Vibrocavitational Homogenizer

2020 ◽  
Vol 9 (4) ◽  
pp. 53-58
Author(s):  
E. V. Flisyuk ◽  
S. S. Belokurov ◽  
I. A. Narkevich ◽  
O. M. Flisyuk ◽  
D. Yu. Ivkin
Keyword(s):  
Solid Phase ◽  
Raw Materials ◽  
Rotation Frequency ◽  
Biologically Active Substances ◽  
Biologically Active ◽  
Rotor Speed ◽  
Particle Crushing ◽  
Fenugreek Seeds ◽  
Average Probability ◽  
Active Substances

Introduction. Vibration cavitation homogenizers are increasingly used in various industries, including the pharmaceutical industry – for the preparation of creams, gels to give them a homogeneous composition, and more recently for the extraction of valuable substances from plant materials. As we have shown earlier, a comparison of the extraction of dioscin from fenugreek seeds, carried out in devices of various designs, under the same conditions for organizing the process showed that the most effective method was the extraction method in a vibro-cavitation field. Obviously, this is due to the fact that cavitation reduces the diffusion resistance of the process and, thus, increases the intensity of the process of transferring the mass of a substance from the solid phase to the solution. However, the extraction process in apparatus of this type is complex and is accompanied by crushing of seeds, which leads to a change in the dispersed composition of the solid phase.Aim. Conduct a theoretical and experimental analysis of the process of grinding hay fenugreek seeds particles in a vibrocavitation homogenizer, accompanied by the extraction of biologically active substances, as well as obtaining dependences that allow evaluating the contribution of grinding to the formation of the dispersed composition of the meal in this apparatus and determining the average particle size as a result of crushing. In earlier works, using the example of the extraction of dioscin from fenugreek seeds, it was shown that an increase in the rotor speed increases the yield of biologically active substances. However, fine grinding of raw materials often leads to the formation of a sediment layer that pollutes the solution with ballast substances and complicates its purification, and also reduces the yield of biologically active substances, therefore, the study of this process is necessary to control the dispersed composition in order to ensure the highest extraction efficiency in devices of this type.Materials and methods. The first stage of the study was the theoretical analysis of the grinding process, since it is a special case of a large class of processes in which the dispersed composition of the solid phase is not constant. Therefore, in this work, for the mathematical description of particle grinding, a model is used that takes into account the kinetic features of the process under consideration. An experimental study of the extraction of valuable components from plant raw materials was carried out in a laboratory setup with a vibro-cavitation homogenizer of periodic action. As a raw material, we used fenugreek seeds purchased from LLC «Stoing», Moscow (Russia), which we used for research. Commodity analysis showed the compliance of raw materials with the requirements of the GF XIV edition. The initial, aqueous solution of ethanol (volume concentration 60 %) with fenugreek seeds was loaded into glass 6, in a volume of 0.2 liters, then the rotor of the apparatus was brought into rotation and brought to a given rotation frequency. The experiments were carried out at a rotation frequency of 1000, 3000 and 5000 rpm (16.7; 50 and 83.3) 1/s. At each value of the rotor speed, the process time varied in the range from 0 to 50 minutes, and the process was carried out for 60, 120, 180, 240 and 300 seconds. Studies carried out for 5 minutes or more showed that the dispersed composition of the meal practically does not change over time, but significantly depends on the rotor speed. Thus, after 5 minutes, a certain stabilization of the dispersed composition occurs and further residence of the material in the apparatus does not lead to a noticeable change in the dispersed composition. After each experiment, the meal was taken, dried, and sieve analysis of the dispersed composition was carried out.Results and discussion. Based on the results obtained by processing the experimental data according to the equation, the values of the average probability of particle crushing were calculated and, as it turned out, it practically does not depend on time, but depends only on the rotor speed. The dependence of the change in the average probability of particle grinding at different rotor speed was obtained. The analysis of these results showed that the value of the average probability of particle grinding in the cavitation homogenizer increases with an increase in the rotor speed, which is quite expected, since the frequency of contacts of particles with the working organs of the apparatus increases. In addition, the obtained dependence for the average probability of particle crushing is linear. This Expression quite accurately describes the values of the change in time of the relative mass of particles in the working range n = 16.7 – 83.3 1/s. Taking these values into account, the experimental and calculated results are in good agreement.Conclusions. The proposed approach and the results obtained can be used to assess the dispersed composition of particles obtained in other designs of devices of similar action.

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