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Acid Sodium Salt (acid + sodium_salt)
Selected AbstractsThe effect of polymers and surfactants on the pour point of palm oil methyl estersEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 4 2007Cheah Han Sern Abstract The objective of this research was to find some additives suitable to reduce the pour point (PP) of palm oil methyl esters. The PP properties of palm oil methyl esters (biodiesel) were evaluated with commercially available polymeric and surfactant compounds with various polarities, molecular sizes and structures. The compounds under study were poly(ethylene glycol), poly(methyl methacrylate), poly(ethylene-co-vinyl acetate), poly(styrene-co-maleic anhydride), poly(ethylene glycol) distearate, poly-(octadecyl methacrylate), poly(1-decene), poly(maleic anhydride- alt -1-octadecene), caprylic acid sodium salt, N -lauroylsarcosine sodium salt, polyoxyethylene(2) cetyl ether and polyoxyethylene(10) cetyl ether. Seven out of the twelve polymeric compounds tested were miscible in palm oil methyl esters due to similar polarities of the solute and biodiesel. The blends of the resultant seven polymeric compounds in palm oil methyl esters were evaluated respectively for their effect on the PP property. Poly-(maleic anhydride- alt -1-octadecene) was able to improve the PP of palm oil methyl esters from 12 to 6,°C when 2,wt-% was added. The cloud point was reduced from 12.9 to 8.1,°C, and the cold filter plugging point was reduced from 12 to 7,°C, whilst the flash point value remained unchanged at 156,°C when 2,wt-% of poly(maleic anhydride- alt -1-octadecene) was added to the palm oil methyl esters. [source] Binding and functional affinity of some newly synthesized phenethylamine and phenoxypropanolamine derivatives for their agonistic activity at recombinant human ,3 -adrenoceptorJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 1 2003Maruf Ahmed ABSTRACT ,3 -Adrenoceptor is the predominant ,-adrenoceptor in adipocytes and has drawn much attention during the investigation for anti-obesity and antidiabetes therapeutics. Thirteen new compounds have been evaluated for their potencies and efficacies as ,3 -adrenoceptor agonists on human ,3 - adrenoceptor expressed in COS-7 and Chinese hamster ovary (CHO) cells using radio ligand binding assay and cyclic AMP (cAMP) accumulation assay. Phenoxypropanolamine derivatives, SWR-0334NA (([E)-[4-[5-[(3-phenoxy-2-hydroxypropyl)amino]-2-pentene,3-yl] phenoxy]acetic acid sodium salt), SWR-0335SA ((E)-[4-[5-[(3-phenoxy-2-hydroxypropyl)amino]-2-pentene,3-yl] phenoxy] acetic acid ethanedioic acid), SWR-0342SA (S-(Z)-[4-[[1-[2-[(2-hydroxy,3-phenoxypropyl)]amino]ethyl]-1-pro-penyl]phenoxy] acetic acid ethanedioic acid), SWR-0348SA-SITA ((E)-[4-[5-[(3-phenoxy-2-hydroxy-propyl)amino]-2-hexene,3-yl] phenoxy]acetic acid ethanedioic acid) and SWR-0361SA ((E)-N-methyl-[4-[5-[(3-phenoxy-2-hydroxypropyl)amino]-2-pentene,3-yl]phenoxy]acetoamide ethanedioic acid) showed higher agonistic activity for the ,3 -adrenoceptor. Among the compounds tested, SWR-0334NA exhibited full agonist activity (%Emax = 100.26) despite its lower binding affinity (pK1 = 6.11). Compounds SWR-0338SA((E)-[4-[5-[(2-phenyl-2-hydroxyethyl)amino]-2-pentene,3-yl]phenoxy]acetic acid ethanedioic acid), SWR-0339SA (S-(E)-[4-[5-[(3-phenoxy-2-hydroxypropyl)amino]-2-pentene,3-yl] phenoxy] acetic acid ethanedioic acid), SWR-0345HA ((E)-2-methyl,3-[4-[2-(2-phenyl-2-hydroxyethyl-amino)ethoxy] phenyl]-2-propenoic acid ethyl ester hydrochloride), SWR-0358SA ((E)-(2-methoxy-ethyl)-[4-[5-[(3-phenoxy-2-hydroxypropyl) amino]-2-pentene,3-yl]phenoxy]acetoamide ethanedioic acid) and SWR-0362SA ((E)-1-[[[4-[5-[(3-phenoxy-2-hydroxypropyl)amino]-2-pentene ,3-yl]phenoxy]-acetyl]carbonyl]piperidine ethanedioic acid) had moderate agonistic activity and were phenethylamine and phenoxypropanolamine derivatives. Compounds SWR-0065HA ([4-[2-[3-[[(3,4-dihydro-4-oxo-[1,2,4]-triazino(4,5-a)indol)-lyl]oxy]-2-hydroxypropylamino]ethoxy]phenyl]acetic acid methyl ester hydrochloride), SWR-0098NA ((E)-[4-[3-[(2-phenyl-2-hydroxyethyl)amino]-1-butenyl] phenoxy]-acetic acid sodium salt) and SWR-0302HA ([4-[[4-[2-(3-chlorophenoxy-2-hydroxypropyl)amino]-E-2-butenyl]oxy]phenoxy]acetic acid hydrochloride) had very low binding affinity towards ,3 -adreno-ceptors and they did not induce cAMP accumulation. We concluded that compounds SWR-0334NA, SWR-0335SA, SWR-0342SA, SWR-0348SA-SITA and SWR-0361SA were potential agonists of human ,3 - adrenoceptor. Further investigation on their selectivity towards ,3 -adrenoceptor could be useful for the exploration of the physiological properties of the ,3 -adrenoceptor. [source] Chromatographic methods for the separation of biocompatible iron chelators from their synthetic precursors and iron chelatesJOURNAL OF SEPARATION SCIENCE, JSS, Issue 17-18 2004Petra Kova, íková Abstract Chromatographic methods have been developed for the separation of the three novel biocompatible iron chelators pyridoxal isonicotinoyl hydrazone (PIH), salicylaldehyde isonicotinoyl hydrazone (SIH), and pyridoxal 2-chlorobenzoyl hydrazone (o-108) from their synthetic precursors and iron chelates. The chromatographic analyses were achieved using analytical columns packed with 5 ,m Nucleosil 120-5 C18. For the evaluation of all chelators in the presence of the synthetic precursors, EDTA was added to the mobile phase at a concentration of 2 mM. The best separation of PIH and its synthetic precursors was achieved using a mixture of phosphate buffer (0.01 M NaH2PO4, 5 mM 1-heptanesulfonic acid sodium salt; pH 3.0) and methanol (55 : 45, v/v). For separation of SIH and its synthetic precursors, the mobile phase was composed of 0.01 M phosphate buffer (pH 6.0) and methanol (60 : 40, v/v). o-108 was analyzed employing a mixture of 0.01 M phosphate buffer (pH 7.0), methanol, and acetonitrile (60 : 20 : 20, v/v/v). These mobile phases were slightly modified to separate each chelator from its iron chelate. Furthermore, a RP-TLC method has also been developed for fast separation of all compounds. The chromatographic methods described herein could be applied in the evaluation of purity and stability of these drug candidates. [source] Determination of serotonin, melatonin and metabolites in gastrointestinal tissue using high-performance liquid chromatography with electrochemical detectionBIOMEDICAL CHROMATOGRAPHY, Issue 2 2009Rosanna M. W. Chau Abstract In this paper we show a simple isocratic chromatographic method for the detection of serotonin and its precursors and metabolites from various types of gastrointestinal tissue. The paper measures for the first time basal measurements of melatonin in the gastrointestinal tract, which has recently been shown to be released from the musosal lining of the gut. Tissue samples were stable following sample preparation in either 0.1 m perchloric acid or mobile phase. Analysis was carried out using a mobile phase consisting of 10% acetonitrile,90% acetate acid buffer pH 4.0 with 2 mm decane,sulfonic acid sodium salt at a column temperature of 50°C. Electrochemical detection was utilized at a potential of +850 mV vs Ag/AgCl reference electrode at 10 µA full-scale deflection. The detection limit of 5-HT and melatonin was 241 and 308 nm respectively for a 10 µL injection. As a result of the method optimization, total analysis was reduced to 30 min. Accurate responses of the tissue samples following sample preparation could be obtained following a week after storage at ,80°C. This method is capable of preparing and analysing of samples from all regions of the gastrointestinal tract. Copyright © 2008 John Wiley & Sons, Ltd. [source] Synthesis of Enantiopure Sulfonimidamides and Elucidation of Their Absolute Configuration by Comparison of Measured and Calculated CD Spectra and X-Ray Crystal Structure DeterminationCHEMISTRY - A EUROPEAN JOURNAL, Issue 2 2010Christin Worch Abstract Straightforward syntheses of enantiopure N -benzoyl- and N - tert -butyloxycarbonyl-protected sulfonimidamides, which can be used as building blocks in newly designed catalysts, are presented. Key synthetic step is a dynamic resolution of a racemic sulfinic acid sodium salt. All subsequent transformations proceed stereospecifically. The absolute configurations at the sulfur atoms of both sulfonimidamides were determined by comparison of measured and calculated CD spectra. An X-ray crystal structure determination of a sulfonimidoylguanidine derivative confirmed this result. [source] Bile acid salt binding with colesevelam HCl is not affected by suspension in common beveragesJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 12 2006Martin Hanus Abstract It has been previously reported that anions in common beverages may bind to bile acid sequestrants (BAS), reducing their capacity for binding bile acid salts. This study examined the ability of the novel BAS colesevelam hydrochloride (HCl), in vitro, to bind bile acid sodium salts following suspension in common beverages. Equilibrium binding was evaluated under conditions of constant time and varying concentrations of bile acid salts in simulated intestinal fluid (SIF). A stock solution of sodium salts of glycochenodeoxycholic acid (GCDC), taurodeoxycholic acid (TDC), and glycocholic acid (GC), was added to each prepared sample of colesevelam HCl. Bile acid salt binding was calculated by high-performance liquid chromatography (HPLC) analysis. Kinetics experiments were conducted using constant initial bile acid salt concentrations and varying binding times. The affinity, capacity, and kinetics of colesevelam HCl binding for GCDC, TDC, and GC were not significantly altered after suspension in water, carbonated water, Coca-Cola®, Sprite®, grape juice, orange juice, tomato juice, or Gatorade®. The amount of bile acid sodium salt bound as a function of time was unchanged by pretreatment with any beverage tested. The in vitro binding characteristics of colesevelam HCl are unchanged by suspension in common beverages. © 2006 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 95:2751,2759, 2006 [source] | ||||||||||