scholarly journals Synthesis and study of complexes of the novel Russian antiviral drug Camphecene with pentacyclic triterpenes of licorice

2020 ◽  
Vol 7 (4) ◽  
pp. 192-198
Author(s):  
S. S. Khizrieva ◽  
E. V. Vetrova ◽  
S. N. Borisenko ◽  
E. V. Maksimenko ◽  
N. I. Borisenko

For the first time, the complexation of pentacyclic triterpenes of licorice (glycyrrhizic acid (GA) and its aglycone, glycyrrhetinic acid (GLA)) with the novel Russian antiviral drug Camphecene (Camph) was investigated. The complexes obtained at different molar ratios were studied using both UV/Vis spectroscopy and mass spectrometry (ESI MS). Formation of the host:guest complexes were registered: GA and GLA molecular complexes (Camph+2GA; Camph+2GLA) with stability constants К = 6.94 106 М-2 and К = 2.89 106 М-2, respectively. The research results demonstrate a considerable potential of ESI MS as a technique for simple and fast detection of formation of the complexes of GA /GLA and the novel drugs.

2021 ◽  
Vol 8 (2) ◽  
pp. 20218202
Author(s):  
S. S. Khizrieva ◽  
E. V. Vetrova ◽  
S. N. Borisenko ◽  
E. V. Maksimenko ◽  
N. I. Borisenko

Traditionally, glycyrrhizic acid has been used to form polydentate complexes. For the first time in the presented paper, the complexation of the Plant’s Flavonoids (Quercetin (Qu) and its glycoside - Rutin (Rut)) with the novel Russian antiviral drug Camphecene (Camph) was investigated. The complexes obtained at different molar ratios were studied using UV/Vis spectroscopy. Formation of the host: guest complexes were registered: Qu and Rut molecular complexes (Camph+2Qu; Camph+2Rut) with a stability constant K = 3.3·108 M-2. Comparison of the binding constants of the obtained complexes shows that the efficiency of Camphecene complexation with the participation of flavonoids is more efficient than with the participation of triterpenoids. Besides, it was found that the complexes of Camphecene with the quercetin and rutin are soluble in water, in contrast to the complexes with triterpenoids, which makes it possible to increase the bioavailability of both Camphecene and flavonoids. The obtained results demonstrate the high potential of flavonoids Qu and Rut to the development of novel pharmaceutical forms using the example of Camphecene in the form of molecular complexes, as the novel forms of delivery.


Molecules ◽  
2019 ◽  
Vol 24 (18) ◽  
pp. 3323 ◽  
Author(s):  
Tao Wang ◽  
Fengjiao Zhang ◽  
Weibing Zhuang ◽  
Xiaochun Shu ◽  
Zhong Wang

The needles of Taxus species contain a large number of bioactive compounds, such as flavonoids. In the present study, the total flavonoid content in leaves of Taxus media and Taxus mairei was 19.953 and 14.464 mg/g, respectively. A total of 197 flavonoid metabolites (70 flavones, 42 flavonols, 26 flavone C-glycosides, 20 flavanones, 15 anthocyanins, 13 isoflavones, 6 flavonolignans, and 5 proanthocyanidins) were identified for the first time by a widely targeted Ultra Performance Liquid Chromatography-Electrospray Ionization-Tandem Mass Spectrometry (UPLC-ESI-MS/MS) method within the two Taxus species, containing 160 common metabolites, with 37 unique metabolites merely determined in T. mairei or T. media. Moreover, 42 differential flavonoid metabolites were screened in the two Taxus species, which showed specific metabolic patterns in isoflavonoid biosynthesis, anthocyanin biosynthesis, and flavone and flavonol biosynthesis pathways. Compared to T. mairei, a more activated phenylpropanoid pathway was found in T. media, which could be responsible for the higher content of total flavonoids in T. media. Our results provide new insights into the diversity of flavonoid metabolites between T. mairei and T. media, and provide a theoretical basis for the sufficient utilization of Taxus species and the development of novel drugs.


2021 ◽  
Author(s):  
Yue Zhao ◽  
Zhaoyi Joey Dai ◽  
Chong Dai ◽  
Xin Wang ◽  
Samridhdi Paudyal ◽  
...  

Abstract Scale inhibitors have been widely used for barite scale control. Our group has developed several barite crystallization and inhibition models to predict the crystallization and inhibition kinetics of pure barite with different inhibitors and calculate the minimum inhibitor concentration (MIC) required. However, instead of pure barite scale formation, the incorporation of Sr2+ can be frequently found in the oilfield, because of the coexistence of Ba2+ and Sr2+ in the produced water, which can influence the kinetics of crystallization and inhibition significantly. As a result, the MIC predicted could be off significantly. Therefore, in this study, the effect of Sr2+ on barite crystallization and inhibition kinetics is quantitatively investigated to evaluate the accuracy of MIC values under various conditions. The induction time of barite with different concentrations of Sr2+ was measured by laser apparatus without or with different concentrations of scale inhibitor diethylenetriamine penta(methylene phosphonic acid) (DTPMP) at the conditions: barite saturation index (SI) from 1.5 to 1.8; temperature (T) from 40 to 70 ℃; and [Sr2+]/[Ba2+] molar ratios from 0 to 15, all with celestite SI < 0. The results show that the induction time of the barite increases with [Sr2+]/[Ba2+] ratio at a fixed barite SI, T and DTPMP dosage. That means the MIC will be overestimated if it is calculated by previous semiempirical pure barite crystallization and inhibition models, without considering the presence of Sr2+. Based on the experimental results, the novel quantitative barite crystallization and inhibition models that include the influence of Sr2+ were developed for the first time as follows: Barite crystallization model with the influence of Sr2+: l o g 10 t 0 B a S O 4 ,   S r = ( 1.523 − 10.88 S I − 895.67 T ( K ) + 5477 S I × T ( K ) + 0.829 × [ C a 2 + ] ) + ( 0.823 S I + 85.44 T ( K ) − 0.667 ) × ( [ Sr 2 + ] [ B a 2 + ] ) Barite inhibition model including the influence of Sr2+ l o g 10 ( t i n h B a s o 4 , S r t 0 B a S O 4 , S r ) = b B a S O 4 , S r × C i n h l o g 10 b B a S O 4 , S r = ( − 2.187 − 1.411 × S I + 1329.29 T ( K ) + 0.153 × p H ) + ( 0.0983 × S I − 74.66 T ( K ) + 0.099 ) × ( [ Sr 2 + ] [ B a 2 + ] ) These novel models are in good agreement with the experimental data. They are used to predict the induction time and MIC more accurately at these common Ba2+ and Sr2+ coexisting scenarios. The observations and new models proposed in this study will significantly improve the barite scale management when Ba2+ and Sr2+ coexist in the oilfield.


1981 ◽  
Vol 36 (9-10) ◽  
pp. 893-895 ◽  
Author(s):  
B. Renner ◽  
A. Henssen ◽  
E. Gerstner

Abstract The novel liehen substance porphyrilic acid methyl ester and pannaric acid are reported the first time in the lichen genus Psoroma. They are constituents in the two varieties of the new species Psoroma tenue as well as in members of the Psoroma hypnorum/paleaceum aggr. and in a hitherto underscribed species from the southern hemisphere. Both dibenzofuranes are characterized by mass spectrometry and UV/VIS spectroscopy. A third compound of unknown structure (Ut) has been found additionally in the two varieties of P. tenue and in some specimens of the P. hypnorum/paleaceum group.


2018 ◽  
Vol 8 (3) ◽  
pp. 247-266
Author(s):  
Michelle L. Wilson

Initially, Oliver Twist (1839) might seem representative of the archetypal male social plot, following an orphan and finding him a place by discovering the father and settling the boy within his inheritance. But Agnes Fleming haunts this narrative, undoing its neat, linear transmission. This reconsideration of maternal inheritance and plot in the novel occurs against the backdrop of legal and social change. I extend the critical consideration of the novel's relationship to the New Poor Law by thinking about its reflection on the bastardy clauses. And here, of course, is where the mother enters. Under the bastardy clauses, the responsibility for economic maintenance of bastard children was, for the first time, legally assigned to the mother, relieving the father of any and all obligation. Oliver Twist manages to critique the bastardy clauses for their release of the father, while simultaneously embracing the placement of the mother at the head of the family line. Both Oliver and the novel thus suggest that it is the mother's story that matters, her name through which we find our own. And by containing both plots – that of the father and the mother – Oliver Twist reveals the violence implicit in traditional modes of inheritance in the novel and under the law.


2017 ◽  
Vol 13 (2) ◽  
pp. 4671-4677 ◽  
Author(s):  
A. M. Abdelghany ◽  
A.H. Oraby ◽  
Awatif A Hindi ◽  
Doaa M El-Nagar ◽  
Fathia S Alhakami

Bimetallic nanoparticles of silver (Ag) and gold (Au) were synthesized at room temperature using Curcumin. Reduction process of silver and gold ions with different molar ratios leads to production of different nanostructures including alloys and core-shells. Produced nanoparticles were characterized simultaneously with FTIR, UV/vis. spectroscopy, transmission electron microscopy (TEM), and Energy-dispersive X-ray (EDAX). UV/vis. optical absorption spectra of as synthesized nanoparticles reveals presence of surface palsmon resonance (SPR) of both silver at (425 nm) and gold at (540 nm) with small shift and broadness of gold band after mixing with resucing and capping agent in natural extract which suggest presence of bimetallic nano structure (Au/Ag). FTIR and EDAX data approve the presence of bimetallic nano structure combined with curcumin extract. TEM micrographs shows that silver and gold can be synthesized separately in the form of nano particles using curcumin extract. Synthesis of gold nano particles in presence of silver effectively enhance and control formation of bi-metallic structure.


2018 ◽  
Author(s):  
Satish Kodali ◽  
Liangshan Chen ◽  
Yuting Wei ◽  
Tanya Schaeffer ◽  
Chong Khiam Oh

Abstract Optical beam induced resistance change (OBIRCH) is a very well-adapted technique for static fault isolation in the semiconductor industry. Novel low current OBIRCH amplifier is used to facilitate safe test condition requirements for advanced nodes. This paper shows the differences between the earlier and novel generation OBIRCH amplifiers. Ring oscillator high standby leakage samples are analyzed using the novel generation amplifier. High signal to noise ratio at applied low bias and current levels on device under test are shown on various samples. Further, a metric to demonstrate the SNR to device performance is also discussed. OBIRCH analysis is performed on all the three samples for nanoprobing of, and physical characterization on, the leakage. The resulting spots were calibrated and classified. It is noted that the calibration metric can be successfully used for the first time to estimate the relative threshold voltage of individual transistors in advanced process nodes.


Author(s):  
G. O. Hutchinson

The chapter looks at the division between poetry and prose in ancient and other literatures, and shows the importance of rhythmic patterning in ancient prose. The development of rhythmic prose in Greek and Latin is sketched, the system explained and illustrated (from Latin). It is firmly established, for the first time, which of the main Greek non-Christian authors 31 BC–AD 300 write rhythmically. The method takes a substantial sample of random sentence-endings (usually 400) from each of a large number of Imperial authors; it compares that sample with one sample of the same size (400) drawn randomly from a range of authors earlier than the invention of this rhythmic system. A particular sort of X2-test is applied. Many Imperial authors, it emerges, write rhythmically; many do not. The genres most likely to offer rhythmic writing are, unexpectedly, narrative: historiography and the novel.


Author(s):  
Robert Louis Stevenson ◽  
Ian Duncan

Your bed shall be the moorcock’s, and your life shall be like the hunted deer’s, and ye shall sleep with your hand upon your weapons.’ Tricked out of his inheritance, shanghaied, shipwrecked off the west coast of Scotland, David Balfour finds himself fleeing for his life in the dangerous company of Jacobite outlaw and suspected assassin Alan Breck Stewart. Their unlikely friendship is put to the test as they dodge government troops across the Scottish Highlands. Set in the aftermath of the 1745 rebellion, Kidnapped transforms the Romantic historical novel into the modern thriller. Its heart-stopping scenes of cross-country pursuit, distilled to a pure intensity in Stevenson’s prose, have become a staple of adventure stories from John Buchan to Alfred Hitchcock and Ian Fleming. Kidnapped remains as exhilarating today as when it was first published in 1886. This new edition is based on the 1895 text, incorporating Stevenson’s last thoughts about the novel before his death. It includes Stevenson’s ‘Note to Kidnapped’, reprinted for the first time since 1922.


2001 ◽  
Vol 56 (7-8) ◽  
pp. 521-525 ◽  
Author(s):  
Denata Kasaj ◽  
Liselotte Krenn ◽  
Sonja Prinz ◽  
Antje Hüfner ◽  
Shi Shan Yuc ◽  
...  

The detailed investigation of a methanolic extract of aerial parts of Achillea pannonica SCHEELE. within a chemotaxonomic study led to the isolation of 6 flavonoid glycosides. Besides rutin, apigenin-7-O-glucopyranoside, luteolin-7-O-glucopyranoside, apigenin-7-O-rutinoside and acacetin-7-O-rutinoside, an unusual flavondiglucoside was isolated. Its structure was established by UV, 1HNMR and 13C NMR spectroscopic methods including 2D-NMR techniques and ESI-MS as luteolin-7,4′-O-β-diglucoside. This substance is reported for the first time in the genus Achillea. Chemotaxonomic aspects are discussed briefly


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