specific rotation
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Pharmaceutics ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 2110
Author(s):  
Ewelina Świątek ◽  
Paula Ossowicz-Rupniewska ◽  
Ewa Janus ◽  
Anna Nowak ◽  
Peter Sobolewski ◽  
...  

The paper presents the synthesis, full identification, and characterization of new salts-L-proline alkyl ester naproxenates [ProOR][NAP], where R was a chain from ethyl to butyl (including isopropyl). All obtained compounds were characterized by Nuclear Magnetic Resonance (NMR), Fourier transform infrared spectroscopy (FTIR), X-ray powder diffractometry (XRD), and in vitro dissolution studies. The specific rotation, phase transition temperatures (melting point), and thermal stability were also determined. In addition, their lipophilicity, permeability, and accumulation in pigskin were determined. Finally, toxicity against mouse L929 fibroblast cells was tested. The obtained naproxen derivatives showed improved solubility and higher absorption of drug molecules by biological membranes. Their lipophilicity was lower and increased with the increase in the alkyl chain of the ester. The derivative with isopropyl ester had the best permeability through pigskin. The use of L-proline isopropyl ester naproxenate increased the permeation of naproxen through the skin almost four-fold. It was also shown that the increase in permeability is not associated with additional risk: all compounds had a similar effect on cell viability as the parent naproxen.


2021 ◽  
Vol 64 (1) ◽  
Author(s):  
Seung-Su Lee ◽  
Hyoung-Geun Kim ◽  
Eun-Ha Park ◽  
Kwang Joong Kim ◽  
Myun-Ho Bang ◽  
...  

AbstractAll parts of Thanakha (Hesperethusa crenulata R.) have been used as traditional skin care herbal material in Myanmar. In this study, coumarins from H. crenulata R. bark were isolated through solvent extraction, systematic solvent fractionation, and repeated column chromatography. Spectroscopic analyses using ESI–MS, 1D NMR (1H and 13C), 2D NMR (gHSQC and gHMBC), specific rotation, circular dichroism, and IR spectrometry revealed three coumarins 2R-7-hydroxy-8-(2,3-dihydroxy-3-methylbutyl)-coumarin (compound 1), peucedanol (compound 2), and methylpeucedanol (compound 3), which were first isolated from Thanakha tree. Antioxidant capacities of three coumarins decreased as follows: compound 2 > compound 3 > compound 1. Treatments of lipopolysaccharide-induced THP-1 human monocytic cells with compounds 2 and 3 at 378.8 μM and 359.7 μM inhibited tumor necrosis factor-α production by approximately 32.7% and 13.3%, respectively, compared with the negative control. In summary, these results suggest that Thanakha bark extracts can be used as a potent antioxidant and anti-inflammatory source for cosmetic ingredients.


2021 ◽  
Vol 7 (10) ◽  
pp. 138
Author(s):  
Gabriela Handzlik ◽  
Katarzyna Rzepka ◽  
Dawid Pinkowicz

The effective combination of chirality and magnetism in a single crystalline material can lead to fascinating cross-effects, such as magneto–chiral dichroism. Among a large variety of chiral ligands utilized in the design and synthesis of chiral magnetic materials, helicenes seem to be the most appealing ones, due to the exceptionally high specific rotation values that reach thousands of deg×cm3×g−1×dm−1, which is two orders of magnitude higher than for compounds with chiral carbon atoms. Despite the sizeable family of transition metal complexes with helicene-type ligands, there are only a few examples of such complexes with lanthanide ions. In this mini-review, we describe the most recent developments in the field of lanthanide-based complexes with helicene-type ligands and summarize insights regarding the further exploration of this family of compounds towards multifunctional chiral lanthanide single molecule magnets (Ln-SMMs).


2021 ◽  
Vol 2056 (1) ◽  
pp. 012030
Author(s):  
E N Vasilchikova ◽  
A D Dmitrieva ◽  
A V Kondakova ◽  
A D Kurilov ◽  
V V Usachev ◽  
...  

Abstract The dispersion of the specific rotation constant of a cholesteric-nematic mixture of 5CB and Ch17 at a low concentration was studied by optical spectroscopy. The dispersion of the anisotropy of the refractive index as a function of the wavelength is studied, and the helical pitch of the cholesteric-nematic mixture is calculated.


2021 ◽  
Vol 16 (7) ◽  
pp. 23-29
Author(s):  
Kumarasamy Suresh ◽  
Selvaraj Vasuki ◽  
Narayanan Mathiyazhagan ◽  
Ranganathan Muthusamy

The MCH assimilation Clavispora lusitaniae MGR5 (KY209902) was isolated from sugarcane juice using a screening medium. The preliminary assimilation was exercised with Clavispora lusitaniae MGR5 grown on synthetic medium and assimilation by pH change of the medium was observed. The specific rotation of R-3- Chloro-1,2-propanediol was -6 (c=2.5, in C2H5OH) in conditions with enatiomeric excess of 92.8 % Clavispora lusitaniae MGR5 product. The sharp peaks in HPLC spectrum of R 3 Chloro-1,2-propanediol in the retention time peak was of 2.38 min and concentration 100%. The structural and dynamic properties of R-3-Chloro-1,2-propanediol in GCMS spectrum were obtained. The IR spectrum, a shallow broad band at wavelength 3309.8 signifies the presence of O-H stretching, the narrow peak at 1087.85 indicates the presence of C=O stretching in conjugation with functional group of R- 3 Chloro-1,2-propanediol(C3H7ClO2). These results concluded that the strain assimilated with stereo inversion of R-3- Chloro-1,2-propanediol via RS 3- chloro-1,2-propanediol. The possibility to produce optically active R-3- Chloro-1,2-propanediol was discussed.


2021 ◽  
Vol 34 (02) ◽  
pp. 776-789
Author(s):  
Nastaran Saghayimarouf ◽  
Majid Monajjemi ◽  
Karim Zare ◽  
Ali Shamel

Carbon nano tubes (CNTS) have two basic structure as single-walled and multi-walled based on hexagonal plexus of carbon atoms. CNTs can serve as platforms to conjugate other compounds specially in medications purposes by immobilization of biomolecules at their surface. Dopamine and serotonin are two biological molecules which have bifunctional activities as hormone and neurotransmitter. These two molecules have important roles as neurotransmitters in the central and peripheral nervous systems but serotonin functions as a mood regulator, while dopamine is connected to the “pleasure center”. In this article we optimized molecular and structural properties of connected dopamine and serotonin with SWNTS with four different diameters (7.0,7.5,7.7 and 10.0 nm) by using molecular quantum methods such as NMR shielding tensor data by B3LYP level of theory with 6-31 G(d) as a basis set, mk and frequency methods. Theoretical computations were performed to study NMR chemical shift data including magnetic shielding tensor (σ, ppm), shielding asymmetry (η), magnetic shielding anisotropy (σaniso), magnetic shielding isotropy (σiso) , skew of a tensor (Κ) and chemical shift anisotropy (Δσ) and span (Ω) at various rotation angles around a specific rotation  , physical and chemical properties of atomic nuclei , frequency data  by B3LYP/6-31g level of theory and POP method using gaussian 09 program.


Author(s):  
Nadia Amessis-Ouchemoukh ◽  
Nacera Maouche ◽  
Amar Otmani ◽  
Anass Terrab ◽  
Khodir Madani ◽  
...  

BACKGROUND: Honey is a vegetable and animal product which comes from nectar and / or honeydew. It is used in different nutritional and therapeutic fields. OBJECTIVE: Melissopalynology and physicochemical analysis of Algerian honeys, determination of their phenolic compounds and authenticity parameters and the evaluation of their antioxidant properties. METHODS: Twenty Algerians honey were studied for their physicochemical parameters (moisture, pH, proteins, proline, hydroxymethylfurfural, ash, color, electrical conductivity, and optical rotation), floral origin and phenolic compounds contents. Antioxidant activities were tested too. RESULTS: Melissopalynologycal analyses revealed that the studied honeys were twelve multifloral, seven Fabaceae, and one Myrtaceae. All honeys were acidic (3.65≤pH≤4.35) and most of them were low in moisture content. The electrical conductivity varied between 0.29 mS/cm and 1.78 mS/cm. Ash, protein and proline contents results showed that the majority of honeys were in agreement with the legislation and were authentic. The color varied from mimosa yellow to dark brown. The specific rotation was levorotatory in most honey samples and the hydroxymethylfurfural values (from 1.5 mg/kg to 34.73 mg/kg) agreed with the international requirements. Honeys were rich in total phenolic compounds, 22.41 (Honey11) to 96.16 (Honey15)  mg gallic acid equivalents/100 g, and flavonoids, 8.90 (Honey11) to 80.02 (Honey 02) mg quercetin equivalents/100 g. Honey samples 15,03, 05, 01, and 06 exerted more than 50% reduction of 1,1-diphenyl-2-picrylhydrazyl and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonate) radicals and were able to reduce iron while honey samples 12, 18, 19, 14, and 11chelate efficiently iron. High significant correlations between physicochemical parameters and antioxidant activities were found. CONCLUSION: The Algerian honeys analyzed were authentic and variations in their quality parameters and phenolics composition were directly associated with their demonstrated antioxidant properties.


Author(s):  
Pavlos Kolias ◽  
Nikolaos Stavropoulos ◽  
Alexandra Papadopoulou ◽  
Theodoros Kostakidis

Coaches in basketball often need to know how specific rotation line-ups perform in either offense or defense and choose the most efficient formation, according to their specific needs. In this research, a sample of 1131 ball possession phases of Greek Basket League was utilized, in order to estimate the offensive and defensive performance of each formation. Offensive and defensive ratings for each formation were calculated as a function of points scored or received, respectively, over possessions, where possessions were estimated using a multiple regression model. Furthermore, a Markov chain model was implemented to estimate the probabilities of the associated formation’s performance in the long run. The model could allow us to distinguish between overperforming and underperforming formations and revealed the probabilities over the evolution of the game, for each formation to be in a specific rating category. The results indicated that the most dominant formation, in terms of offense, is Point Guard-Point Guard-Small Forward-Power Forward-Center, while defensively schema Point Guard-Shooting Guard-Small Forward-Center-Center had the highest rating. Such results provide information, which could operate as a supplementary tool for the coach’s decisions, related to which rotation line-up patterns are mostly suitable during a basketball game.


2021 ◽  
Author(s):  
Waki Ikegami ◽  
Hiroshi Kamitakahara ◽  
Yoshikuni Teramoto ◽  
Toshiyuki Takano

Abstract Cellulose, which comprises D-glucose and L-glucose (D,L-cellulose), was synthesized from D-glucose (1D) and L-glucose (1L) via cationic ring-opening polymerization. Specifically, the ring-opening copolymerization of 3-O-benzyl-2,6-di-O-pivaloyl-β-D-glucopyranoside (2D) and 3-O-benzyl-2,6-di-O-pivaloyl-β-D-glucopyranoside (2L), synthesized from compounds 1D and 1L, respectively, in a 1:1 ratio, afforded 3-O-benzyl-2,6-di-O-β-D,L-glucopyranan (3DL) with a degree of polymerization (DPn) of 28.5 (Mw/Mn = 1.90) in quantitative yield. The deprotection of compound 3DL and subsequent acetylation proceeded smoothly to afford acetylated compound 4DL with a DPn of 18.6 (Mw/Mn = 2.08). The specific rotation of acetylated compound 4DL was + 0.01°, suggesting that acetylated compound 4DL was optically inactive cellulose triacetate. Furthermore, before acetylation, compound 4DL was an optically inactive cellulose comprising an almost racemic mixture of D-glucose and L-glucose. Compound 4DL was an amorphous polymer. This is the first reported synthesis of optically inactive D,L-cellulose.


Molbank ◽  
10.3390/m1198 ◽  
2021 ◽  
Vol 2021 (2) ◽  
pp. M1198
Author(s):  
Rebeca González-Fernández ◽  
Pascale Crochet ◽  
Victorio Cadierno

The title compound was synthesized by electrophilic cyanation of commercially available (R)-4-chloro-α-methylbenzylamine with cyanogen bromide in diethyl ether, and isolated as a yellow oil in 84% yield. It was characterized by 1H and 13C{1H] NMR, IR, HRMS, and specific rotation measurements.


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