Search results for "Propylamine"
showing 10 items of 36 documents
A microanalytical method for ammonium and short-chain primary aliphatic amines using precolumn derivatization and capillary liquid chromatography.
2007
Abstract A new microscale method is presented for the determination of ammonium and primary short-chain aliphatic amines (methylamine, ethylamine, propylamine, n -butylamine and n -pentylamine) in water. The assay uses precolumn derivatization with the reagent o -phthaldialdehyde (OPA) in combination with the thiol N -acetyl- l -cysteine (NAC), and capillary liquid chromatography with UV detection at 330 nm. The described method is very simple and rapid as no preconcentration of the analytes is necessary, and the volume of sample required is only 0.1 mL. Under the proposed conditions good linearity has been obtained up to a concentration of the analytes of 10.0 mg L −1 , the limits of detec…
Amphetamine and methamphetamine determination in urine by reversed-phase high-performance liquid chromatography with sodium 1,2-napthoquinone 4-sulfo…
1995
A rapid method is described for the identification and determination of amphetamine and methamphetamine in human urine samples by liquid chromatography with UV-Vis detection. The samples were transferred onto a C18 solid-phase extraction column and chromatographed on a Hypersil ODS RP C18, 5 microns (250 x 4 mm I.D.) with an acetonitrile-water elution gradient containing propylamine. Under these conditions, the amines are eluted with a short retention time. The procedure has been applied to the determination of amphetamine and methamphetamine in the range 0.3-4.0 micrograms/ml in spiked urine samples. The detection limits at 280 nm were 4 and 2 ng/ml for amphetamine and methamphetamine, res…
Derivatization of amines in solid-phase extraction supports with 9-fluorenylmethyl chloroformate for liquid chromatography
1997
Abstract A new method based on reaction in solid-phase extraction cartridges with 9-fluorenylmethyl chloroformate is described for improved derivatization of amines prior to liquid chromatography. The effects of the reaction conditions, the kinetics of the reaction and the kind of packing material on the derivatization have been evaluated. The reliability of the described approach has been tested by derivatizing propylamine, diethylamine, diethanolamine, glycine, glutamic acid, p-aminobenzoic acid and β-phenylethylamine. Reaction yields compared with those of the analogous solution derivatizations were in the 44–169% range, and satisfactory linearity was achieved at concentrations of the am…
An aptamer-gated silica mesoporous material for thrombin detection.
2013
An aptamer-capped mesoporous material for the selective and sensitive detection of &-thrombin in human plasma and serum has been prepared and characterised.
DOTAGA-anhydride: a valuable building block for the preparation of DOTA-like chelating agents.
2012
International audience; A DOTA derivative that contains an anhydride group was readily synthesized by reacting DOTAGA with acetic anhydride and its reactivity was investigated. Opening the anhydride with propylamine led to the selective formation of one of two possible regioisomers. The structure of the obtained isomer was unambiguously determined by 1D and 2D NMR experiments, including COSY, HMBC, and NOESY techniques. This bifunctional chelating agent offers a convenient and attractive approach for labeling biomolecules and, more generally, for the synthesis of a large range of DOTA derivatives. The scope of the reaction was extended to prepare DOTA-like compounds that contained various f…
Increase by 5-hydroxykynuramine of spontaneous acetylcholine release from myenteric neurons: mediated by serotonin M receptors
1987
The effects of 5-hydroxykynuramine (5-OH-K) and of 3-(2-amino-5-hydroxyphenyl)-propaneamine (AHPP) on spontaneous and electrically evoked release of [3H]acetylcholine were studied in the guinea-pig myenteric plexus longitudinal muscle preparation preincubated with [3H]choline. 5-OH-K caused a concentration-dependent increase in spontaneous [3H]acetylcholine release (EC50 5.3 microM). This effect was diminished in the presence of a desensitizing concentration of 5-hydroxytryptamine (5-HT). AHPP (1-100 microM) did not affect the spontaneous outflow of [3H]acetylcholine. The electrically evoked release of [3H]acetylcholine was significantly reduced in the presence of 100 microM of either 5-OH-…
Studies on the reliability of a bihyperbolic functional absorption model. II. Phenylalkylamines
1987
Evidence is given that demonstrates the reliability of the bihyperbolic equation, proposed by Pla-Delfina and Moreno, in fitting the correlation between absorption rate constants (ka) found in the small intestine and in the colon of the living anesthetized rat, and partition constants (1/R.F−1), for a series of phenylalkylamines, a group of compounds which differ largely from others which have been tested. Emphasis is laid on the nonexistence of an optimum of lipophilicity for intestinal absorption/partition correlation: This feature makes inapplicable the probabilistic approaches to the reported data.
Modulation of high impulsivity and attentional performance in rats by selective direct and indirect dopaminergic and noradrenergic receptor agonists
2011
Rationale Impulsivity is associated with a number of psychiatric disorders, most notably attention deficit/hyperactivity disorder (ADHD). Drugs that augment catecholamine function (e.g. methylphenidate and the selective noradrenaline reuptake inhibitor atomoxetine) have clinical efficacy in ADHD, but their precise mechanism of action is unclear. Objective The objective of this study is to investigate the relative contribution of dopamine (DA) and noradrenaline (NA) to the therapeutic effects of clinically effective drugs in ADHD using rats selected for high impulsivity on the five-choice serial reaction time task (5CSRTT). Methods We examined the effects of direct and indirect DA and NA rec…
Efficacy and safety of extended-release guanfacine hydrochloride in children and adolescents with attention-deficit/hyperactivity disorder: A randomi…
2014
AbstractGuanfacine extended-release (GXR), a selective α2A-adrenergic agonist, is a non-stimulant treatment for attention-deficit/hyperactivity disorder (ADHD). This study assessed the efficacy (symptoms and function) and safety of dose-optimized GXR compared with placebo in children and adolescents with ADHD. An atomoxetine (ATX) arm was included to provide reference data against placebo. Patients (6–17 years) were randomized at baseline to dose-optimized GXR (0.05–0.12mg/kg/day – 6–12 years: 1–4mg/day; 13–17 years: 1–7mg/day), ATX (10–100mg/day) or placebo for 4 or 7 weeks. The primary efficacy measure was change from baseline in ADHD Rating Scale version IV (ADHD-RS-IV). Key secondary me…
Rapid one-pot propargylamine synthesis by plasmon mediated catalysis with gold nanoparticles on ZnO under ambient conditions
2013
Surface plasmon excitation of gold nanoparticles on ZnO in the presence of an aldehyde, an amine and phenylacetylene led to rapid and selective formation of propargylamines with good yields (50-95%) at room temperature. Plasmon mediated catalysis is the best available route for this ternary coupling.