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201.
Iltaf?ShahEmail author James?Barker Declan?P.?Naughton Stephen?J.?Barton Syed?Salman?Ashraf 《Chemistry Central journal》2016,10(1):80
Glomerular filtration rate (GFR) is usually determined by estimation of iothalamate (IOT) clearance. We have developed and validated an accurate and robust method for the analysis of IOT in human plasma and urine. The mobile phase consisted of methanol and 50 mM sodium phosphate (10:90; v/v). Flow rate was 1.2 mL/min on a C18 reverse phase column, Synergi-hydro (250 × 4.6 mm) 4 µm 80 Å, with an ultraviolet detector set to 254 nm. Acetonitrile was used for the deproteination and extraction of IOT from human plasma and urine. Precision and accuracy were within 15% for IOT in both plasma and urine. The recoveries of IOT in urine and plasma ranged between 93.14% and 114.74 and 96.04–118.38%, respectively. The linear range for urine and plasma assays were 25–1500 and 1–150 µg/mL respectively. The lower limits of detection were 0.5 µg/mL for both urine and plasma, with no interference from plasma and urine matices. This method has been fully validated according to FDA guidelines and the new HPLC assay has been applied to a new formulation of IOT (Conray? 43), to calculate GFR in healthy volunteers. The new method is simple, less expensive and it would be instrumental in future clinical and pharmacokinetic studies of iothalamate in kidney patients. 相似文献
202.
Syeda Shahzadi Batool Quratulain Syed Muhammad Salman Haider 《Journal of Coordination Chemistry》2018,71(9):1380-1391
The syntheses, characterization, and crystal structures of the reaction products of Cu2+ with imidazole (Himz) and different aromatic carboxylates, viz.: [Cu(Himz)2(cinn)2(H2O)] (1), [Cu(Himz)2(paba)2] (2) and [Cu(Himz)2(clba)2] (3) (cinn– = C9H7O2–, paba– = C7H6NO2–, clba– = C7H4ClO2–) are described and studied by spectroscopic (UV–visible, FTIR) measurements. Single-crystal X-ray diffraction analyses indicate that each complex is monomeric. The metal ion in 1 adopts square-pyramidal coordination geometry arising from two imidazole nitrogens, two cinnamate oxygens, and an apical aqua. The metal ions of 2 and 3, however, assume a square planar configuration, which is realized by coordination of two nitrogens of two imidazoles and two oxygens; in both complexes, the imidazole moieties are trans to each other. TGA results indicate that upon heating, these complexes lose their carboxylate anions first, followed by removal of the imidazole molecules. 相似文献
203.
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205.
New di-(β-keto) schiff bases were prepared. The molecular structure of those di-(β-keto) schiff bases was determined by 1H and C-13 nmr spectroscopy. 相似文献
206.
Anthony Linden Fatemeh Ghorbani‐Salman Pour Roland A. Breitenmoser Heinz Heimgartner 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(5):634-637
The morpholine ring of the title dione, C13H15NO3, shows a boat conformation that is distorted towards a twist‐boat, with the boat ends being the two Csp3 atoms of the ring. The benzyl substituent is in the favoured `exo' position. In the monothione derivative, (±)‐6‐benzyl‐3,3‐dimethyl‐5‐thioxomorpholin‐2‐one, C13H15NO2S, this ring has a much flatter conformation that is midway between a boat and an envelope, with the dimethyl end being almost planar. The orientation of the benzyl group is `endo'. The dithione derivative, (±)‐6‐benzyl‐3,3‐dimethylmorpholine‐2,5‐dithione, C13H15NOS2, has two symmetry‐independent molecules, which show different puckering of the morpholine ring. One molecule has a flattened envelope conformation distorted towards a screw‐boat, while the conformation in the other molecule is similar to that in the monothione derivative. Intermolecular hydrogen bonds link the molecules in the three compounds, respectively, into centrosymmetric dimers, infinite chains, and dimers made up of one of each of the symmetry‐independent molecules. 相似文献
207.
Aurora-A kinase plays a central role in mitosis, where aberrant activation contributes to cancer by promoting cell cycle progression, genomic instability, epithelial-mesenchymal transition, and cancer stemness. Aurora-A kinase inhibitors have shown encouraging results in clinical trials but have not gained Food and Drug Administration (FDA) approval. An innovative computational workflow named Docking-based Comparative Intermolecular Contacts Analysis (dbCICA) was applied—aiming to identify novel Aurora-A kinase inhibitors—using seventy-nine reported Aurora-A kinase inhibitors to specify the best possible docking settings needed to fit into the active-site binding pocket of Aurora-A kinase crystal structure, in a process that only potent ligands contact critical binding-site spots, distinct from those occupied by less-active ligands. Optimal dbCICA models were transformed into two corresponding pharmacophores. The optimal one, in capturing active hits and discarding inactive ones, validated by receiver operating characteristic analysis, was used as a virtual in-silico search query for screening new molecules from the National Cancer Institute database. A fluorescence resonance energy transfer (FRET)-based assay was used to assess the activity of captured molecules and five promising Aurora-A kinase inhibitors were identified. The activity was next validated using a cell culture anti-proliferative assay (MTT) and revealed a most potent lead 85(NCI 14040) molecule after 72 h of incubation, scoring IC50 values of 3.5–11.0 μM against PANC1 (pancreas), PC-3 (prostate), T-47D and MDA-MB-231 (breast)cancer cells, and showing favorable safety profiles (27.5 μM IC50 on fibroblasts). Our results provide new clues for further development of Aurora-A kinase inhibitors as anticancer molecules. 相似文献
208.
Various oxime-ether derivatives of cholesterol have been synthesized by the alkylation of the steroidal oxime with 1-(2-chloroethyl) pyrrolidine hydrogen chloride/chloroethylamine hydrochloride in the presence of sodium methoxide in dry methanol. The structures of these compounds were elucidated by IR 1H NMR, FAB mass spectroscopic methods and elemental analyses. The anti-bacterial activity was first tested in vitro by the disk diffusion method against two Gram-positive and two Gram-negative bacteria, and then the minimum inhibitory concentration (MIC) of compounds were determined. The results showed that the chloro derivatives exhibited better anti-bacterial activity than the standard drug chloramphenicol. 相似文献
209.
We consider the descendants of self-adjointly extended Hamiltonians in supersymmetric quantum mechanics on a half-line, on an interval, and on a punctured line or interval. While there is a 4-parameter family of self-adjointly extended Hamiltonians on a punctured line, only a 3-parameter sub-family has supersymmetric descendants that are themselves self-adjoint. We also address the self-adjointness of an operator related to the supercharge, and point out that only a sub-class of its most general self-adjoint extensions is physical. Besides a general characterization of self-adjoint extensions and their supersymmetric descendants, we explicitly consider concrete examples, including a particle in a box with general boundary conditions, with and without an additional point interaction. We also discuss bulk-boundary resonances and their manifestation in the supersymmetric descendant. 相似文献
210.