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291.
S. Zheng R.L. Beissinger L.R. Sehgal D.T. Wasan 《Journal of Dispersion Science and Technology》2013,34(1-2):235-245
A preparation of Ketamine [2-(Chlorophenyl)-2-(methylamino) cyclohexanone, C13H16ClNO, anesthetic agent] in oil in water multiple emulsion for prolonged drug release was formulated and evaluated. Ketamine, the cyclohexylamine, is used as a short-acting anaesthetic in humans and in some animal species [1]. Ketamine is poorly bound to plasma proteins and has a half-life of approximately 4 hours following intravenous injection [2]. Ketamine leaves the blood very rapidly to be distributed into the tissues with a high lipid solubility [2]. The recommended dosage of intravenous Ketamine is 2.5-20mg/kg [3]. The LD50 injected intraperitoneally in mice and rats is 100 times the intravenous and 30 times the intramuscular dose used in humans. The objective of this study was to test the concept that a multiple emulsion could be formulated which has high porosity and lower viscosity at 37°C consistent with its intended use for sustained drug release and to prolong the half-life of the anesthesia. The results showed that the Ketamine (100mg/ml in inner phase) released 8.2% at 10 minutes, 67.0% at 30 minutes, and 95.5% at 60 minutes from the Ketamine/O/W multiple emulsion in a well-controlled manner. 相似文献
292.
Kewal Krishan Singal 《合成通讯》2013,43(11):1047-1052
4,5-Diaryl-3-.styryl-4,5-dihydro[l,2,4] oxadiazoles have been synthesized through a faoile, 1,3-dipolar oyclo-addition of azomethines and phenylaorylonitrile oxide generated in situ, in a single step process. 相似文献
293.
D. P. Singh Monika Kamboj Krishan Kumar Kiran Jain Chetan Sharma K. R. Aneja 《Russian Journal of Inorganic Chemistry》2011,56(9):1396-1401
A series of the macrocyclic complexes is synthesized by condensation of acetonylacetone and thiocarbohydrazide in the presence
of divalent metal salts in the methanolic medium. The complexes are of the type: [M(TML)X2] where, M = Co(II), Ni(II), Cu(II), Zn(II) and Cd(II); X = Cl− CH3COO− and TML is a tetradentate macrocyclic ligand. The complexes have been characterized with the help of various physicochemical
techniques like elemental analyses, conductance measurements, magnetic measurements, NMR, infrared and electronic spectral
studies. The low value of molar conductance indicates them to be non-electrolyte. On the basis of various studies a distorted
octahedral geometry may be proposed for all the complexes. All the synthesized metal complexes were also tested for their
in vitro antibacterial activities against some bacterial strains. The results obtained were compared with standard antibiotic:
Ciprofloxacin. Some of the tested complexes shows good antibacterial activities against some bacterial strains. 相似文献
294.
Vivek K. Gupta Shaveta Mahajan Naresh K. Satti Krishan A. Suri G. N. Qazi 《Journal of chemical crystallography》2008,38(10):769-773
Abstract (20R,22R)-6α,7α-Epoxy-5α,27-dihydroxy-1-oxowitha-2,24-dienolide (27-hydroxy-withanolide B) was isolated from Withania somnifera. The structure of the withanolide was established by spectral analysis and X-ray diffraction studies. The compound crystallizes
in the orthorhombic space group P212121 with unit cell parameters: a = 9.2163(3), b = 11.1828(4), c = 23.6146(9) ?, Z = 4. The crystal structure was refined to R = 0.0495 for 3,284 observed reflections. All the rings of the steroid skeleton are trans connected. Rings A and B exist in
a half-chair conformation, ring C a chair, and five membered ring D is intermediate between a half-chair and an envelope.
The δ-lactone ring E adopts a distorted sofa conformation. The twist along the length of the steroid nucleus is −6.5°. The
characteristic pattern observed in the packing diagram is the appearance of twisted chains of molecules packed together to
form layers.
Index Abstract Isolation and crystal structure analysis of (20R,22R)-6α,7α-epoxy-5α,27-dihydroxy-1-oxowitha-2,24-dienolide.
相似文献
295.
The aim of this study to focused on bioinspired synthesis of silver nanoparticles (AgNPs) as a viable alternative to eradicate the existing physicochemical processes. In this context, the bioinspired AgNPs were synthesized using leaf extract of M. indica. Optimization of the experimental conditions for the rapid and high yield of AgNPs in minimum investment of time and expense have been carried out along with their antibacterial efficacy evaluated. For this reason, the variation of parameters like the concentration of the silver precursors, reducing agent, time, pH, and temperature of synthesis were realized. Synthesized AgNPs were characterized by UV-Visible spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM) techniques. UV-Visible spectra gave surface plasmon resonance (SPR) at 440 nm for AgNPs. Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) techniques were further confirmed the synthesis and crystalline nature of AgNPs respectively. Transmission electron microscopy (TEM) observed spherical shapes of synthesized AgNPs within range 5~20 nm. The results of the current study indicate that optimization process play a pivotal role in the AgNPs synthesis and biogenic synthesized AgNPs might be used against bacterial pathogens. 相似文献
296.
297.
Christine Elian Benjamin Mourot Camil Benbouziyane Prof. Jean-Pierre Malval Sonia Lajnef Dr. Fabienne Peyrot Dr. Florian Massuyeau Dr. Olivier Siri Prof. Denis Jacquemin Dr. Simon Pascal Prof. Davy-Louis Versace 《Angewandte Chemie (International ed. in English)》2023,62(43):e202305963
A near-infrared-absorbing heptamethine ( HM+ ) incorporating three bulky benzo[cd]indole heterocycles was designed to efficiently prevent self-aggregation of the dye, which results in a strong enhancement of its photoinitiating reactivity as compared to a parent bis-benzo[cd]indole heptamethine ( HMCl+ ) used as a reference system. In this context, we highlight an efficient free-radical NIR-polymerization up to a 100 % acrylates C=C bonds conversion even under air conditions. Such an important initiating performance was obtained by incorporating our NIR-sensitizer into a three-component system leading to its self-regeneration. This original photoredox cycle was thoroughly investigated through the identification of each intermediary species using EPR spectroscopy. 相似文献