Highly Diastereoselective Reactions of Isoxazolidine-4,5-diols with Grignard Reagents: A New Approach to anti,syn-γ-Amino-α,β-diols

Synthesis ◽  
2020 ◽  
Author(s):  
Ondrej Záborský ◽  
Róbert Fischer ◽  
Lukáš Ďurina ◽  
Tomáš Malatinský ◽  
Ján Moncol

AbstractAn investigation of the reaction of 3,4-trans-isoxazolidine-4,5-diols with Grignard reagents is described for the first time. Their resemblance to five-membered cyclic hemiacetals allows them to react as α-hydroxy-β-(hydroxyamino)aldehydes in a highly stereoselective manner, providing anti,syn-γ-(hydroxyamino)-α,β-diols in moderate yields and with good to excellent syn-diastereoselectivities, which can be improved by the addition of anhydrous cerium chloride. The obtained (hydroxyamino­)diols serve as suitable precursors of anti,syn-γ-amino-α,β-diols that represent valuable scaffolds for the synthesis of various biologically active compounds.

Synthesis ◽  
2020 ◽  
Author(s):  
Ebrahim Kianmehr ◽  
Hadi Afaridoun

Abstract ortho-C–H bond halogenation of anilides and N-aryl carbamates using easily available N-halosuccinimides (NXS) as the active halogenation reagent in the presence of nickel or silver catalyst has been developed. This method provides a new approach to 2-haloanilides and carbamates, which may serve as starting materials for the synthesis of pharmaceutically and biologically active compounds.


2020 ◽  
Vol 12 ◽  
Author(s):  
Congcong Zhu ◽  
Tianyi Zhong ◽  
Baoqi Zuo

Background: Snail mucus (SM) is secreted by the pedal gland of snails, and has a fibrous structure when it crawls upside down on the plane. It contains biologically active compounds that have medical functions, such as glycol acid, natural antibiotics, and glycoprotein. Methods: For this paper, we prepared fibers using electrospinning to simulate this natural fiber for the first time, and we can produce the nanofiber with mucus from a snail. The effects of dissolution time and the spun solution were also investigated. Result: The results show that biomimetic nanofibers with different diameters can be obtained using electrospinning. When the concentration of the spun liquid was increased from 6wt% to 8wt%, a fiber with about a 200 nm diameter can be obtained. Adjusting the concentration plays a crucial role in electrospinning.


2021 ◽  
pp. 99-104
Author(s):  
O. A. Chunikhina ◽  
M. P. Razgonova ◽  
A. M. Zakharenko ◽  
K. S. Golokhvast

Relevance. A number of scientific studies confirm that consumption of fruits and vegetables can reduce the risk of certain chronic diseases, such as cancer and cardiovascular diseases, for example, consumption of fresh tomatoes and tomato products is inversely proportional to the development of certain types of cancer. Tomato Solanum lycopersicum L. contains a large number of polyphenolic complexes, which are biologically active compounds. In this article, the authors have attempted for the first time to present the complete metabolomic composition of Solanum lycopersicum extracts.Materials and methods: As an object of research, authors used the extracts of Solanum lycopersicum L., from the collection of the Federal Research Center N.I. Vavilov All-Russian Institute of Plant Genetic Resources, grown and collected at the Far Eastern Experiment Station Branch of the Federal State Budgetary Scientific Institution in September 2020 (varieties: k-5351 Ont77 13, Canada; k-3149 Rehovoth, Israel; 2698 Ukraine). High performance liquid chromatography (HPLC) in combination with a BRUKER DALTONIKS ion trap (tandem mass spectrometry) was used to identify target analytes in extracts obtained by the maceration method.Discussion: The results of initial studies revealed the presence of 36 biologically active compounds, of which 22 were identified for the first time in Solanum lycopersicum L. These are Apigenin, Luteolin, Kaempferol, Taxifolin, Myricetin, Coutaric acid, Caffeoylmalic acid, Caftaric acid, Dicaffeoylquinic acid, coumarins Fraxetin, and Fraxetin-7-O-beta-glucuronide, Pelargonidin, Salvianolic acid D, Rosmanol, Colnelenic acid, Ethyl rosemary, lignan Medioresinol-O-hexoside, Squalene, etc. The findings will help to intensify future research into the development and production of various functional food products containing targeted extracts of Solanum lycopersicum L.


INEOS OPEN ◽  
2021 ◽  
Author(s):  
N. D. Chkanikov ◽  
◽  
A. S. Golubev ◽  

Using hexafluoroacetone and trifluoropyruvic acid esters as representative examples, the results of investigations on the reactions of polyfluorinated carbonyl compounds with arylamines, cyclic azomethine–enamines, and nitrogen-containing heterocycles are reviewed. For the first time, the peculiarities of the C-oxyalkylation of nitrogen-containing π-systems with polyfluorinated carbonyl compounds are considered systematically. The results on biological assays of the resulting fluorine-containing products of the C-oxyalkylation are presented. The promising routes for further development of this field from the viewpoint of the creation of new biologically active compounds are outlined.


2018 ◽  
Author(s):  
Honggui Lv ◽  
Li-Jun Xiao ◽  
Dongbing Zhao ◽  
Qi-Lin Zhou

Herein, we realized the first linear-selective hydroarylation of unactivated alkenes and styrenes with organoboronic acids by introducing directing groupon alkenes. Our method is highly efficient and scalable, and provides a modular route to assemble structurally diverse alkylarenes, especially for γ-aryl butyric acid derivatives, which have been widely utilized as chemical feedstocks to access multiple marketed drugs, and biologically active compounds.<br>


2020 ◽  
Vol 5 (443) ◽  
pp. 85-91
Author(s):  
Ibrayev M.K., ◽  
◽  
Takibayeva A.T., ◽  
Fazylov S.D., ◽  
Rakhimberlinova Zh.B., ◽  
...  

This article presents studies on the targeted search for new derivatives of azoles, such as benzthiazole, 3,5-dimethylpyrazole, 1,3,4-oxadiazole-2-thione, 1,3,4-thiadiazole. The possibility of combining in one molecule of the azole ring with other cyclic compounds: the alkaloid cytisine, morpholine, furan and some arenes has been studied. To obtain new compounds, the reactions of bromination, acylation, and interaction with isothiocyanates were studied. Optimal synthesis conditions were studied for all reactions. It was found that the reaction of 4-bromo-3,5-dimethylpyrazole with isothiocyanates, in contrast to the previously written derivatives of anilines, takes a longer time and requires heating the reaction mixture. The combination of a pirasol fragment with halide substituents often results in an enhanced therapeutic effect. The synthesized 2-bromine-N-(6-rodanbenzo[d]thiazole-2-yl)acetamide, due to the alkylbromide group, is an important synth in the synthesis of new benzthiazole derivatives. Its derivatives combine in one molecule the rest of rhodanbenzthiazole with alkaloid cytisine and biogenic amine morpholine and are potentially biologically active compounds, since the molecule structure contains several pharmacophoric fragments: benzthiazole and alkaloid (amine) heterocycles, rhodane and urea groups. The mechanism of formation of 1,3,4-oxadiazole-2-tyons from hydrazides under action on them by carbon disulfide was studied and assumed. It was shown that dithiocarbamates in acidic medium decompose with the release of hydrogen sulfide and the formation of highly reactive isothiocyanate group. Then, intra-molecular cyclization occurs, with the formation of end products - 1,3,4-oxadiazole-2-thions. The structures of the synthesized compounds were studied by 1H and 13C NMR spectroscopy. All synthesized substances are potentially biologically active compounds, since they contain several pharmacophore fragments in their structure.


2020 ◽  
Vol 27 (6) ◽  
pp. 838-853 ◽  
Author(s):  
Madalina Icriverzi ◽  
Valentina Dinca ◽  
Magdalena Moisei ◽  
Robert W. Evans ◽  
Mihaela Trif ◽  
...  

: Among the multiple properties exhibited by lactoferrin (Lf), its involvement in bone regeneration processes is of great interest at the present time. A series of in vitro and in vivo studies have revealed the ability of Lf to promote survival, proliferation and differentiation of osteoblast cells and to inhibit bone resorption mediated by osteoclasts. Although the mechanism underlying the action of Lf in bone cells is still not fully elucidated, it has been shown that its mode of action leading to the survival of osteoblasts is complemented by its mitogenic effect. Activation of several signalling pathways and gene expression, in an LRPdependent or independent manner, has been identified. Unlike the effects on osteoblasts, the action on osteoclasts is different, with Lf leading to a total arrest of osteoclastogenesis. : Due to the positive effect of Lf on osteoblasts, the potential use of Lf alone or in combination with different biologically active compounds in bone tissue regeneration and the treatment of bone diseases is of great interest. Since the bioavailability of Lf in vivo is poor, a nanotechnology- based strategy to improve the biological properties of Lf was developed. The investigated formulations include incorporation of Lf into collagen membranes, gelatin hydrogel, liposomes, loading onto nanofibers, porous microspheres, or coating onto silica/titan based implants. Lf has also been coupled with other biologically active compounds such as biomimetic hydroxyapatite, in order to improve the efficacy of biomaterials used in the regulation of bone homeostasis. : This review aims to provide an up-to-date review of research on the involvement of Lf in bone growth and healing and on its use as a potential therapeutic factor in bone tissue regeneration.


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