scholarly journals Synthesis and Oxidative Transformations of New Chiral Pinane-Type γ-Ketothiols: Stereochemical Features of Reactions

Molecules ◽  
2021 ◽  
Vol 26 (17) ◽  
pp. 5245
Author(s):  
Olga M. Lezina ◽  
Svetlana N. Subbotina ◽  
Larisa L. Frolova ◽  
Svetlana A. Rubtsova ◽  
Denis V. Sudarikov

Chiral γ-ketothiols, thioacetates, thiobenzoate, disulfides, sulfones, thiosulfonates, and sulfonic acids were obtained from β-pinene for the first time. New compounds open up prospects for the synthesis of other polyfunctional compounds combining a biologically active pinane fragment with various pharmacophore groups. It was shown that the syntheses of sulfanyl and sulfonyl derivatives based on 2-norpinanone are characterized by high stereoselectivity in comparison with similar reactions of pinocarvone. The conditions for the preparation of diastereomerically pure thioacetyl and thiobenzoyl derivatives based on pinocarvone, as well as for the chemoselective oxidation of γ-ketothiols with chlorine dioxide to the corresponding thiolsulfonates and sulfonic acids, were selected. The effect of the VO(acac)2 catalyst on the increase in the yields of thiosulfonates was shown. A new direction of the transformation of thiosulfonates with the formation of sulfones was revealed. In the case of pinocarvone-based sulfones, the configuration is inversed at the C2 atom. An epimerization scheme is proposed.

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.


2017 ◽  
Vol 15 (10) ◽  
pp. 2163-2167 ◽  
Author(s):  
Zhouting Rong ◽  
Antonio M. Echavarren

The polycyclisation of polyeneynes catalyzed by gold(i) has been extended for the first time to the simultaneous formation of up to four carbon–carbon bonds, leading to steroid-like molecules with high stereoselectivity in a single step with low catalyst loadings.


Molecules ◽  
2021 ◽  
Vol 26 (11) ◽  
pp. 3371
Author(s):  
Chao-Qun Wang ◽  
Li-Wei Yi ◽  
Lin Zhao ◽  
Yu-Zhen Zhou ◽  
Fang Guo ◽  
...  

Wild ginseng (W-GS), ginseng under forest (F-GS, planted in mountain forest and growing in natural environment), and cultivated ginseng (C-GS) were compared via HPLC-DAD and HPLC-IT-TOF-MSn. A total of 199 saponins, including 16 potential new compounds, were tentatively identified from 100 mg W-GS (177 saponins in W-GS with 11 new compounds), F-GS (56 saponins with 1 new compound), and C-GS (60 saponins with 6 new compounds). There were 21 saponins detected from all the W-GS, F-GS, and C-GS. Fifty saponins were only detected from W-GS, including 23 saponins found in ginseng for the first time. Contents of ginsenosides Re (12.36–13.91 mg/g), Rh1 (7.46–7.65 mg/g), Rd (12.94–12.98 mg/g), and the total contents (50.52–55.51 mg/g) of Rg1, Re, Rf, Rb1, Rg2, Rh1, and Rd in W-GS were remarkably higher than those in F-GS (Re 1.22–3.50 mg/g, Rh1 0.15–1.49 mg/g, Rd 0.19–1.49 mg/g, total 5.69–18.74 mg/g), and C-GS (Re 0.30–3.45 mg/g, Rh1 0.05–3.42 mg/g, Rd 0.17–1.68 mg/g, total 2.99–19.55 mg/g). Contents of Re and Rf were significantly higher in F-GS than those in C-GS (p < 0.05). Using the contents of Re, Rf, or Rb1, approximately a half number of cultivated ginseng samples could be identified from ginseng under forest. Contents of Rg1, Re, Rg2, Rh1, as well as the total contents of the seven ginsenosides were highest in ginseng older than 15 years, middle–high in ginseng between 10 to 15 years old, and lowest in ginseng younger than 10 years. Contents of Rg1, Re, Rf, Rb1, Rg2, and the total of seven ginsenosides were significantly related to the growing ages of ginseng (p < 0.10). Similarities of chromatographic fingerprints to W-GS were significantly higher (p < 0.05) for F-GS (median: 0.824) than C-GS (median: 0.745). A characteristic peak pattern in fingerprint was also discovered for distinguishing three types of ginseng. Conclusively, wild ginseng was remarkably superior to ginseng under forest and cultivated ginseng, with ginseng under forest slightly closer to wild ginseng than cultivated ginseng. The differences among wild ginseng, ginseng under forest, and cultivated ginseng in saponin compositions and contents of ginsenosides were mainly attributed to their growing ages.


Author(s):  
Maltseva E.M. ◽  
Egorova I.N. ◽  
Pinchuk L.G.

Pale-flowered licorice (Glycyrrhiza pallidiflora Maxim.) is the pea family (Fabaceae) perennial herb. It is a Russian Far East endemic. Pale-flowered licorice refers to the false (not sweet) licorice section (Pseudoglycyrrhiza Krug.), which do not accumulate glycyrrhizin derivatives. The G. pallidiflora successful introduction has been carried out over the past 5 years in the “Apothecary garden” territory, FRC UUH SB RAS, Kemerovo. Phytochemical studies screening biologically active compounds main classes of the plant aerial part confirmed the presence of a complex of phenolic compounds. The content of catechin derivatives and condensed-type tannins - proanthocyanidins (PAC) data in G. pallidiflora herb were obtained for the first time. In different years of cultivation, licorice herb accumulates phenolic compounds - up to 2.83 ± 0.22% in terms of gallic acid, flavonoids - up to 2.44 ± 0.03% in terms of rutin and PAC in terms of cyanidine chloride - up to 2.61 ± 0.11%. It was found that the maximum content of the phenolic compounds and PAC sum was observed in the herb for 4 years development. The greatest number of flavonoids accumulates in the herb harvested in the 3rd year of cultivation. A positive significant linear relation was found between antioxidant activity (AOA) and the total phenolic compounds and PAC content (r≥0.98). Considering that BAC with IC values ≤ 50 μg / ml in the DPPH assay refer to active antioxidant’s licorice herb can be classified as a plant with high antioxidant potential. It was found that the iron chelating activity of the G. pallidiflora herb is in direct dependence (r≥0.94) on the content of flavonoids. The obtained results demonstrate the importance of further study of this plant as a source of BAC, including plant antioxidants.


Molecules ◽  
2018 ◽  
Vol 23 (10) ◽  
pp. 2448
Author(s):  
Jun Wang ◽  
Hongshuai Yang ◽  
Yang Liu ◽  
Kelsang Norbo ◽  
Kewu Zeng ◽  
...  

Eight azukisapogenol triterpene glycosides, including five new compounds, oxychiliotriterpenosides A–E (1–5), two new methyl glucuronide derivatives that proved to be artifacts, oxychiliotriterpenoside E-glucuronic acid methyl ester (6) and myrioside B-glucuronic acid methyl ester (7), and a known one, myrioside B (8), was isolated from the aerial part of Oxytropis chiliophylla Royle. Their structures were elucidated based on extensive spectroscopic analyses and chemical methods. Triterpene glycosides were first obtained from O. chiliophylla, and those containing a galactose unit (1, 2, 5 and 6) and diglucosidic or triglucosidic linkage at C-29 (1–4), were reported from Oxytropis species for the first time, which might be recognized as a chemotaxonomic feature of O. chiliophylla. All isolated compounds were evaluated for their anti-inflammatory activities against NO production using lipopolysaccharide (LPS)-induced RAW 264.7 cells, but no compounds showed potent inhibition on NO production.


1999 ◽  
Vol 71 (6) ◽  
pp. 1147-1151 ◽  
Author(s):  
L. Zeng ◽  
J. Su ◽  
Yongli Zhong ◽  
Xiong Fu ◽  
T. Peng ◽  
...  

eLife ◽  
2018 ◽  
Vol 7 ◽  
Author(s):  
Albert Lu ◽  
Paulina Wawro ◽  
David W Morgens ◽  
Fernando Portela ◽  
Michael C Bassik ◽  
...  

Extracellular vesicles mediate transfer of biologically active molecules between neighboring or distant cells, and these vesicles may play important roles in normal physiology and the pathogenesis of multiple disease states including cancer. However, the underlying molecular mechanisms of their biogenesis and release remain unknown. We designed artificially barcoded, exosomal microRNAs (bEXOmiRs) to monitor extracellular vesicle release quantitatively using deep sequencing. We then expressed distinct pairs of CRISPR guide RNAs and bEXOmiRs, enabling identification of genes influencing bEXOmiR secretion from Cas9-edited cells. This approach uncovered genes with unrecognized roles in multivesicular endosome exocytosis, including critical roles for Wnt signaling in extracellular vesicle release regulation. Coupling bEXOmiR reporter analysis with CRISPR-Cas9 screening provides a powerful and unbiased means to study extracellular vesicle biology and for the first time, to associate a nucleic acid tag with individual membrane vesicles.


Author(s):  
С. В. Шершова

Проведено експериментальне обґрунтування біо-конверсії відходів вирощування (полови) ехінацеїпурпурової (Echinacea purpurea (L.) Moench.) таехінацеї блідої (Echinacea pallida (Nutt) Nutt.).Доведена висока активність екстрактів полови зехінацеї пурпурової, що проявлялася у стимуляціїросту тест-культури. Встановлено, що найвищустимулюючу активність мають екстракти поло-ви ехінацеї пурпурової: водні за концентрації0,01 %, спиртові – 0,01–0,001 %; до того ж іззбільшенням концентрації спирту в екстрактахзнижувалась їх активність. Вперше встановлено,що полова ехінацеї містить специфічні білки –лектини, активність яких у відходах ехінацеї блі-дої значно перевищувала ехінацею пурпурову. Роз-роблено технологічні схеми отримання лектинівта екстрактів біологічно активних речовин із від-ходів вирощування (полови) для їх ефективноговикористовування. The experimental foundation bioconversion of waste product of growing (chaff), purple coneflower(Echinacea purpurea (L.) Moench.) and pale coneflower (Echinacea pallida (Nutt.) Nutt.) was to carriedout. The high activity of extracts of coneflower chaff, which had growth-stimulating effect to the testculture, was proved. Found that the highest stimulating activity has the extract of chaff purpleconeflowers: aqueous solution at concentrations of 0.01 %, alcohol-0.01 %-0.001 % and with increasingconcentration of alcohol in the extracts decreased their activity. For the first time it has been shown thatchaff of Echinacea contains specific proteins - lectins, and their activity in the waste product of paleconeflower significantly exceeded then activity in the waste product of purple coneflower. Technologicalschemes to get of lectins and extracts of biologically active substances from waste growing product(chaff), was worked out for their effective use.


2018 ◽  
Vol 4 (3) ◽  
pp. 27-36 ◽  
Author(s):  
Irina Stepanenko ◽  
Semen Yamashkin ◽  
Yuliya Kostina ◽  
Alyona Batarsheva ◽  
Mikhail Mironov

Introduction. The problem of antibiotic resistance of microorganisms is becoming more urgent in the twenty-first century. Microorganisms possess an evolutionary adaptive capacity. Non-adherence to the basic principles of rational antibiotic therapy leads to menacing consequences. More and more pathogenic microbes are becoming resistant to two or more antibiotics. The search for new compounds with antimicrobial activity is one of the principles for overcoming the antibiotic resistance of microorganisms. Materials and methods. Eighteen test-strains of microorganisms and more than 2000 clinical strains of microorganisms, representating the families Micrococcaceae, Streptococcaceae, Enterobacteriaceae, Moraxellaceae, Pseudomonadaceae, Sphingomonadaceae, Xanthomonadaceae were studied for sensitivity to the compounds derived from 4-, 5-, 6- and 7-aminoindoles. A method of serial dilutions to determine the minimal inhibitory concentration (MIC) of the compounds under study was used in the study, as well as a disc diffusion method. Results and discussion. Sensitivity of the test-strains and of clinical strains of microorganisms to the resulting compounds was studied. The compounds based on substituted 4-, 5-, 6-, 7-aminoindoles showed different activity against the test strains and experimental strains of microorganisms in vitro. It was found that the marked antibacterial activity was exhibited by the compounds containing a trifluoromethyl group. The most significant activity was noted in amides and pyrroloquinolones based on 4-aminoindole, 6-aminoindole and 7-aminoindole.The most effective compounds with laboratory codes 5D, 7D, 39D, S3, HD, 4D showed a pronounced antibacterial activity. Conclusion. Antimicrobial activity of the substituted amides and pyrroloquinolines on the basis of 4-, 5-, 6-, 7-aminoindoles was etermined in our study, as well as the spectra of their action against Gram-positive and Gram-negative microorganisms, which are causative agents of non-specific and certain specific human infectious diseases. Moreover, we evaluated the synthetic potentials of the substituted 4-, 5-, 6-, 7-aminoindoles as the starting compounds for synthesizing a series of indolylamides and pyrroloquinolines. Also, the prospects for targeted synthesis of biologically active compounds based on indole-type aromatic amines were determined.


2021 ◽  
Vol 16 (9) ◽  
pp. 1934578X2110437
Author(s):  
Bui H. Tai ◽  
Dan T. Hang ◽  
Do T. Trang ◽  
Pham H. Yen ◽  
Phan T. T. Huong ◽  
...  

Five conjugated polyene ketones (1-5) were isolated from the methanol extract of the marine sponge Clathria ( Thalysias) reinwardti (Vosmaer, 1880) living in the coastal waters of Vietnam. Their structures were determined to be 8-(2′,3′,4′-trimethylphenyl)-6-methyl-oct-3( E),5( E),7( E)-trien-2-one (1), 13-apoastaxanthinone (2), 9-apoastaxanthinone (3), 2,3-dehydro-4-oxo- β-ionone (4), and 4-(2′,3′,4′-trimethylphenyl)-but-3( E)-en-2-one (5), by extensive analysis of high-resolution electron spray ionization mass spectrum (HR-ESI-MS), one-dimensional, and two-dimensional (2D) nuclear magnetic resonance (NMR) spectra, as well as by comparison of the spectral data with those reported in the literature. Compound 1 was new, compounds 2 to 4 were isolated from nature for the first time, and the chemical structure as well as the NMR assignments, of 5 were indicated by 2D NMR for the first time. Additionally, compound 5 exhibited cytotoxic activity against the human cancer cells SK-LU-1, SK-Mel-2, MCF-7, and Hep-G2 with half-minimal inhibitory concentration (IC50) values of 15.12 ± 3.43, 17.41 ± 2.83, 33.12 ± 3.39, and 34.38 ± 3.52 µM, respectively, but displayed only a weak cytotoxic effect on the normal HEK-239A cells (IC50 64.67 ± 3.67 µM). Compound 5 also significantly increased Caspase-3 activity in SK-LU-1 cells at concentrations of 10, 15, and 20 µM.


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