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101.
(S)-2,4-Dihydroxybutyl-4-hydroxybenzoate was prepared in an extremely simple and practical way with high enantiomeric excess (99% ee) using Jacobsen’s Hydrolytic Kinetic Resolution technique as a key step and source of chirality. 相似文献
102.
Murugesan Dinesh Subramanyam Deepika Rajendran HarishKumar Chinnadurai Immanuel Selvaraj Selvaraj Mohana Roopan 《Applied biochemistry and biotechnology》2018,185(2):450-463
The current study indicates that octyl-β-D-glucopyranoside (OGP) as a detergent which has the ability to make the lipid layer stiff. OGP was subjected for toxicity studies and in vitro cytotoxicty assays on cancerous HeLa and non-cancerous myoblasts H9c2 cell lines. Test against aquatic organisms were carried out in Artemia salina and LC50 values were calculated. Hemolytic activity tested for blood bio-compalibity showed hemolysis rate of 10–16%, followed by thrombolytic activity to burst the clots in blood. Also, the samples showed good lysis when compared to the standard streptokinase. Furthermore, α-amylase activity has been carried out to check the inhibition of α-amylase by the OGP. Finally, antibacterial activity has been tested against four different pathogens and their MIC values have been calculated. 相似文献
103.
Umesh Todmal Suresh P. Sulochana Mohd Zainuddin Ravi Kanth Bhamidipati Swapan Kumar Samanta Gurulingappa Hallur Sridharan Rajagopal Sriram Rajagopal Ramesh Mullangi 《Chromatographia》2018,81(3):457-468
A sensitive and rapid LC–MS/MS method was developed and validated for the simultaneous quantitation of five selective KCNQ channel openers, namely ICA-27243, ML-213, PF-05020182, SF-0034 and flupirtine in mice plasma as per regulatory guideline. The analytes and the internal standard (IS; flupirtine-d 4 ) were extracted from 50 µL mice plasma by liquid–liquid extraction, followed by chromatographic separation using an Atlantis C18 column with an isocratic mobile phase comprising 0.2% formic acid: acetonitrile (20:80, v/v) at a flow rate of 0.6 mL min?1 within 2.5 min. Detection and quantitation was done by multiple reaction monitoring on a triple quadrupole mass spectrometer following the transitions: m/z 268.9 → 140.8, 258.1 → 95.1, 367.2 → 269.1, 322.2 → 248.2, 305.7 → 196.4 and 309.1 → 196.1 for ICA-27243, ML-213, PF-05020182, SF-0034, flupirtine and the IS, respectively, in the positive ionization mode. The calibration curves were linear from 1.00 to 2008 ng mL?1 for all the analytes with r2 ≥ 0.99. The intra- and inter-batch accuracy and precision (% CV) across quality controls varied from 90.0 to 113 and 2.64 to 13.0; 93.8 to 114 and 3.15 to 14.9%, respectively, for all the analytes. Analytes were found to be stable under different stability conditions. The method was applied to a pharmacokinetic study in mice. 相似文献
104.
Rajnikant Dinesh Nusrat Aziz M. Mushfiq Mahboob Alam Azhar U. Khan 《Journal of chemical crystallography》2006,36(12):793-798
7a-Aza-B-homostigmast-5-eno [7a, 7-d] tetrazole-3β-yl chloride (C29H47N4Cl) was synthesized for its crystallographic analysis and to investigate the role of intra- and intermolecular interactions in steroids. It crystallizes in the monoclinic space group C2 with unit cell parameters: a = 38.481(2), b = 6.661(3), c = 11.111 (6) ?, β = 94.49 (4)o; λ( MoKα) = 0.71069 ?, V = 2839(2) ?3, and Z = 4. The structure has been solved by direct methods using X-ray diffraction techniques. The final reliability index for the computed structure is 0.0597 for 1252 observed reflections. Except the five-membered ring, all other rings of the steroid nucleus exist in non-planar conformations. The structure is stabilized by C–H···N intermolecular interaction.Supplementary material CCDC-267926 contains the supplementary crystallographic data for this paper. These data can be obtained free of charge at www.ccdc.cam.an.uk/uk/conts/retrieving.html or from the Cambridge Crystallographic Data Centre
(CCDC), 12 Union Road, Cambridge CB2 1EZ, United Kingdom; Fax: $+$44(0) 1223-336033; e-mail: deposit@ccdc.cam.ac.uk. 相似文献
105.
A highly sensitive and specific LC-MS/MS method has been developed and validated for the estimation of torcetrapib (TTB) with 100 microL hamster/dog plasma using DRL-16126 as an internal standard (IS). The API-4000 Q Trap LC-MS/MS was operated under multiple-reaction monitoring mode using the electrospray ionization technique. The assay procedure involved extraction of TTB and IS from plasma with acetonitrile, which yielded consistent recoveries of 65.73 and 94.01% for TTB and 79.68 and 90.70% for IS in hamster and dog plasma, respectively. The total chromatographic run time was 3.0 min and the elution of TTB and IS occurred at approximately 2.25 and 2.20 min, respectively. The resolution of peaks was achieved with 0.01 m ammonium acetate:acetonitrile (15:85, v/v) at a flow rate of 0.40 mL/min on an Inertsil ODS-3 column. The method was proved to be accurate and precise at linearity range of 1.00-200 ng/mL with a correlation coefficient (r) of > or = 0.993. The method was rugged with 1.00 ng/mL as the lower limit of quantitation. TTB was stable in the battery of stability studies. The application of the assay to preclinical pharmacokinetic studies confirmed the utility of the assay to derive hamster/dog pharmacokinetic parameters. 相似文献
106.
Dr. Thangavel Vijayakanth Supriya Sahoo Premkumar Kothavade Vijay Bhan Sharma Prof. Dr. Dinesh Kabra Dr. Jan K. Zaręba Dr. Kadhiravan Shanmuganathan Prof. Dr. Ramamoorthy Boomishankar 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2023,135(3):e202214984
Hybrid materials possessing piezo- and ferroelectric properties emerge as excellent alternatives to conventional piezoceramics due to their merits of facile synthesis, lightweight nature, ease of fabrication and mechanical flexibility. Inspired by the structural stability of aminophosphonium compounds, here we report the first A3BX6 type cyanometallate [Ph2(iPrNH)2P]3[Fe(CN)6] ( 1 ), which shows a ferroelectric saturation polarization (Ps) of 3.71 μC cm−2. Compound 1 exhibits a high electrostrictive coefficient (Q33) of 0.73 m4 C−2, far exceeding those of piezoceramics (0.034–0.096 m4 C−2). Piezoresponse force microscopy (PFM) analysis demonstrates the polarization switching and domain structure of 1 further confirming its ferroelectric nature. Furthermore, thermoplastic polyurethane (TPU) polymer composite films of 1 were prepared and employed as piezoelectric nanogenerators. Notably, the 15 wt % 1 -TPU device gave a maximum output voltage of 13.57 V and a power density of 6.03 μW cm−2. 相似文献
107.
Dr. Sushil Kumar Najat Maher Aldaqqa Dr. Emad Alhseinat Dr. Dinesh Shetty 《Angewandte Chemie (International ed. in English)》2023,62(35):e202302180
Recent years have seen the emergence of capacitive deionization (CDI) as a promising desalination technique for converting sea and wastewater into potable water, due to its energy efficiency and eco-friendly nature. However, its low salt removal capacity and parasitic reactions have limited its effectiveness. As a result, the development of porous carbon nanomaterials as electrode materials have been explored, while taking into account of material characteristics such as morphology, wettability, high conductivity, chemical robustness, cyclic stability, specific surface area, and ease of production. To tackle the parasitic reaction issue, membrane capacitive deionization (mCDI) was proposed which utilizes ion-exchange membranes coupled to the electrode. Fabrication techniques along with the experimental parameters used to evaluate the desalination performance of different materials are discussed in this review to provide an overview of improvements made for CDI and mCDI desalination purposes 相似文献
108.
Let a be a regular element of a ring R. If either K:=r R (a) has the exchange property or every power of a is regular, then we prove that for every positive integer n there exist decompositionswhere \(Y_{n} \subseteq a^{n}R\) and E n ?R/a R. As applications we get easier proofs of the results that a strongly π-regular ring has stable range one and also that a strongly π-regular element whose every power is regular is unit-regular.
相似文献
$$R_{R} = K \oplus X_{n} \oplus Y_{n} = E_{n} \oplus X_{n} \oplus aY_{n}, $$
109.
Kasalova V Allen WD Schaefer HF Pillai ED Duncan MA 《The journal of physical chemistry. A》2007,111(31):7599-7610
In support of mass-selected infrared photodissociation (IRPD) spectroscopy experiments, coupled-cluster methods including all single and double excitations (CCSD) and a perturbative contribution from connected triple excitations [CCSD(T)] have been used to study the V+(H2O) and ArV+(H2O) complexes. Equilibrium geometries, harmonic vibrational frequencies, and dissociation energies were computed for the four lowest-lying quintet states (5A1, 5A2, 5B1, and 5B2), all of which appear within a 6 kcal mol(-1) energy range. Moreover, anharmonic vibrational analyses with complete quartic force fields were executed for the 5A1 states of V+(H2O) and ArV+(H2O). Two different basis sets were used: a Wachters+f V[8s6p4d1f] basis with triple-zeta plus polarization (TZP) for O, H, and Ar; and an Ahlrichs QZVPP V[11s6p5d3f2g] and Ar[9s6p4d2f1g] basis with aug-cc-pVQZ for O and H. The ground state is predicted to be 5A1 for V+(H2O), but argon tagging changes the lowest-lying state to 5B1 for ArV+(H2O). Our computations show an opening of 2 degrees -3 degrees in the equilibrium bond angle of H2O due to its interaction with the metal ion. Zero-point vibrational averaging increases the effective bond angle further by 2.0 degrees -2.5 degrees, mostly because of off-axis motion of the heavy vanadium atom rather than changes in the water bending potential. The total theoretical shift in the bond angle of about +4 degrees is significantly less than the widening near 9 degrees deduced from IRPD experiments. The binding energies (D0) for the successive addition of H2O and Ar to the vanadium cation are 36.2 and 9.4 kcal mol(-1), respectively. 相似文献
110.
James-Smith MA Shekhawat D Moudgil BM Shah DO 《Langmuir : the ACS journal of surfaces and colloids》2007,23(4):1640-1644
We propose that one can deduce very insightful information regarding the drug and fatty acid binding capacity of microemulsions through simple turbidity experiments. Pluronic F127-based oil-in-water microemulsions of various compositions were synthesized and titrated to turbidity with concentrated amitriptyline, an antidepressant drug. We observed that, above certain Pluronic F127 concentrations, turbidity was never observed, irrespective of how much amitriptyline was added to the microemulsion. We also observed that whenever sodium caprylate fatty acid was not included in the microemulsion formulation, turbidity never occurred. On the basis of these findings, we were able to determine the point at which all sodium caprylate present in the microemulsion formulation was bound to the F127 in the microemulsion (i.e., no fatty acid was free in the bulk in monomer form). By the same logic we were also able to determine how much amitriptyline was binding to the microemulsions. We also measured the dynamic surface tension, foamability, and fabric wetting time of the microemulsion formulations to further prove the hypothesis that all fatty acid is bound to the F127 in the microemulsion above a critical Pluronic F127 concentration. On the basis of this research, we have concluded that there are approximately 11 molecules of sodium caprylate fatty acid bound per molecule of Pluronic F127 and approximately 12 molecules of amitriptyline bound per molecule of Pluronic F127 in the optimal microemulsion formulation. These findings give us valuable information about the charge density at the oil/water interface and about the mechanism of binding of the drug to the microemulsion. 相似文献