Home About us Contact
|
Home About us Contact | ||
|
|
||
Amino Compounds (amino + compound)
Selected AbstractsA short synthesis of 5,7-bis(dialkylamino)-2-methyl- 8 -hydroxyquinolinesJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 5 2001George B. Okide The bromine atoms of the title compound were replaced by the requisite amino compound to afford the desired derivatives in high yields. Thus, six target compounds viz- bis(diethylamino)-, bis(dibutylamino)-, bis(dicyclohexylamino)-, dipyrrolidino-, dipiperidino-, and dipiperazino-derivatives were obtained and characterized by spectral and elemental analyses. [source] Cross-reactivity among p -amino group compounds in sulfonamide fixed drug eruption: diagnostic value of patch testingCONTACT DERMATITIS, Issue 2 2004P. Tornero We studied 28 patients with fixed drug eruption (FDE) caused by sulfonamide antibiotics to investigate cross-reactivity between sulfonamide derivatives and p -amino compounds and to explore the usefulness of patch testing, as an alternative to controlled oral challenge testing (COCT), in diagnosis within this clinical area. COCT with sulfamethoxazole (SMX), sulfadiazine (SDZ), sulfamethizole (SMZ), furosemide (FU), procaine (PRO) and glipizide (GPZ) was performed. Patch testing (PT) with SMX and SDZ was carried out. In all patients, the diagnosis of FDE was confirmed by positive COCT and allergy to trimethoprim ruled out by COCT. 42.8 and 31.8% of the SMX-induced FDE patients reacted to SMZ and SDZ, respectively. All patients (n = 28) tolerated FU, PRO and GPZ. COCT performed with the 3 sulfonamide antibiotics in 12 patients was positive in 2 subjects with the 3 drugs, in 2 patients only with SMX and SMZ and in the remaining 8, SMX was the only causative drug. PT was positive in 5 of 25 patients positive on COCT. The probability of obtaining a positive PT was higher among patients who had a residual lesion than that among those who lacked this. Cross-reactivity between different sulfonamide antibiotics is thus variable, being most likely between SMX and SMZ. We have found no cross-reactivity between sulfonamide antibiotics and other sulfonamide derivatives or p -amino drugs in FDE. PT is a useful tool in the diagnosis of FDE, especially if there are residual lesions, because it avoided the need for COCT in 20% of patients. [source] Analytical potential of 6-oxy-(N -succinimidyl acetate)-9-(2'-methoxycarbonyl) fluorescein for the determination of amino compounds by capillary electrophoresis with laser-induced fluorescence detectionELECTROPHORESIS, Issue 10 2005Liwei Cao Abstract The analytical potential of a fluorescein analogue, 6-oxy-(N -succinimidyl acetate)-9-(2'-methoxycarbonyl) fluorescein (SAMF), for the first time synthesized in our laboratory, as a labeling reagent for the labeling and determination of amino compounds by capillary electrophoresis (CE) with laser-induced fluorescence (LIF) detection was investigated. Biogenic monoamines and amino acids were chosen as model analytes to evaluate the analytical possibilities of this approach. The derivatization conditions and separation parameters for the biogenic amines were optimized in detail. The derivatization was performed at 30°C for 6 min in boric acid buffer (pH 8.0). The derivatives were baseline-separated in 15 min with 25 mM boric acid running buffer (pH 9.0), containing 24 mM SDS and 12.5% v/v acetonitrile. The concentration detection limit for biogenic amines reaches 8×10,11 mol·L,1 (signal-to-noise ratio = 3). The application of CE in the analysis of the SAMF-derivatized amino acids was also exploited. The optimal running buffer for amino acids suggested that weak acidic background electrolyte offered better separation than the basic one. The proposed method was applied to the determination of biogenic amines in three different beer samples with satisfying recoveries varying from 92.8% to 104.8%. Finally, comparison of several fluorescein-based probes for amino compounds was discussed. With good labeling reaction, excellent photostability, pH-independent fluorescence (pH 4,9), and the resultant widely suited running buffer pH, SAMF has a great prospect in the determination of amino compounds in CE. [source] Bismuth-catalyzed cyclization of amino-1,6-enynesHETEROATOM CHEMISTRY, Issue 6 2008Kimihiro Komeyama Bi(OTf)3 effectively catalyzed the cyclization of amino-1,6-enynes, leading to bicyclic amine and cyclopentadienyl amino compounds. The selectivity of the products depends on the substitution pattern of the olefinic moiety. 19F NMR trace experiment of the reaction and other results indicate a novel alkynophilicity of the bismuth species. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:644,648, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20490 [source] Impact of Elevated PCO2 on Mass Flow of Reduced Nitrogen in Trees,JOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 12 2006Xi-Ping Liu Abstract To analyze the effects of elevated carbon dioxide concentration (PCO2) on the mass flow of reduced nitrogen (N) in the phloem and xylem of trees, juvenile beech (Fagus sylvatica L.) and spruce (Picea abies (L.) Karst.) were grown in phytotrons and exposed to ambient and elevated PCO2 (plus 687.5 mg/m3 CO2) for three growing seasons. Elevated PCO2 significantly decreased the mass flow of N from the shoot to roots of beech by significantly reducing the concentration of soluble amino compounds in the phloem, even if the area of conductive phloem of cross-sectional bark tissue was significantly increased, because of less callus deposition in the sieve elements. In spruce, the downward mass flow of reduced N also tended to be decreased, similar to that in beech. Resembling findings in the phloem, N mass flow from roots to shoot in both tree species was significantly diminished owing to significantly reduced concentrations of amino compounds in the xylem and a lower transpiration rate. Therefore, the mass flow of reduced N between shoots and roots of trees was mainly governed by the concentrations of soluble amino compounds in the phloem and xylem in relation to the loading of reduced N in both long-distance transport pathways. (Managing editor: Ya-Qin Han) [source] Control of Nitrate Uptake by Phloem-Translocated Glutamine in Zea mays L. SeedlingsPLANT BIOLOGY, Issue 4 2002P. Pal'ove-Balang Abstract: The putative role of glutamine, exported from leaves to roots, as a negative feedback signal for nitrate uptake was investigated in Zea mays L. seedlings. Glutamine (Gln) was supplied by immersion of the tip-cut leaves in a concentrated solution. Nitrate (NO3,) uptake was measured by its depletion in amino acid-free medium. The treatment with Gln resulted in a strong inhibition of nitrate uptake rate, accompanied by a significant enrichment of amino compounds in root tissue. The effect of N-availability on NO3, uptake was determined in split-root cultures. The plants were subjected to complete or localized N supply. Inducible NO3, uptake systems were also induced in N-deprived roots when the opposite side of the root system was supplied with KNO3. The inhibitory effect of Gln was unaffected by localized N supply on one side of the split-root. The potential role of Gln in the shoot-to-root control of NO3, uptake is discussed. [source] Hydrogen-bonding interaction between poly(,-caprolactone) and low-molecular-weight amino compoundsPOLYMER INTERNATIONAL, Issue 4 2001Takumi Watanabe Abstract The specific interactions between several low-molecular-weight diamino compounds and poly(,-caprolactone) (PCL) have been investigated by FT-IR. It was found that PCL and 3,3,-diaminodiphenylmethane (3,3,-DADPM) interact through strong intermolecular hydrogen bonds in the blend. Thermal and mechanical properties of PCL/3,3,-DADPM blends were investigated by DSC and tensile measurements, respectively. The glass transition temperature of the blend increases while both the melting point and the elongation-at-break of the blend decrease with the increase of 3,3,-DADPM content. Besides 3,3,-DADPM, several other low-molecular-weight compounds containing two amino groups, such as o -phenylenediamine or 1,6-diaminohexane, were also added into PCL and the corresponding blend systems were investigated by FT-IR and DSC. The effect of the chemical structure of the additives on the properties of PCL is discussed. © 2001 Society of Chemical Industry [source] Chiral stationary phase covalently bound with a chiral pseudo-18-crown-6 ether for enantiomer separation of amino compounds using a normal mobile phaseCHIRALITY, Issue 3 2005Keiji Hirose Abstract In order to apply the excellent chiral recognition ability of chiral pseudo-18-crown-6 ethers that we developed to chiral separation, we prepared a chiral stationary phase (CSP) by immobilizing a chiral pseudo-18-crown-6-type host on 3-aminopropyl silica gel. A chiral column was prepared by the slurry-packing method in a stainless steel HPLC column. A liquid chromatography system using this CSP combined with the detection by mass spectrometry was used for enantiomer separation of amino compounds. A normal mobile phase can be used on this CSP as opposed to conventional dynamic coating-type CSPs. Enantiomers of 18 common natural amino acids were efficiently separated. The chiral separation observed for amino acid methyl esters, amino alcohols, and lipophilic amines was fair using this HPLC system. In view of the correlation between the enantiomer selectivity observed in chromatography and the complexion in solution, the chiral recognition in host,guest interactions might contribute to this enantiomer separation. Chirality 17:142,148, 2005. © 2005 Wiley-Liss, Inc. [source] | |||||||||||||