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1.
The title compound (C2H7NO·C7H4N2O6) has been obtained by the reaction of etha- nolamine with 3,5-dinitrobenzoic acid in deionized water at room temperature. The crystal crystal- lizes in orthorhombic, space group P212121 with a = 6.048(2), b = 9.146(3), c = 21.955(7)(A), C9H11N3O7, Mr = 273.21, Z = 4, V = 1214.3(7)(A)3, Dc = 1.494 g/cm3, F(000) = 568, μ(MoKα) = 0.131 mm-1, R1 = 0.0338 and wR2 = 0.0497. The new organic adduct is composed of one ethanolamine and one 3,5-dinitrobenzoic acid, which are linked up by O-H…O and N-H…O types of hydrogen bonds to form a nine-membered ring and an eleven-membered ring, extending into a one-dimensional network structure. 相似文献
2.
3.
On the refluxing ofM(II) oxalate (M=Mn, Co, Ni, Cu, Zn or Cd) and 2-ethanolamine in chloroform, the following complexes were obtained: MnC2O4·HOCH2CH2NH2·H2O, CoC2O4·2HOCH2CH2NH2, Ni2(C2O4)2·5HOCH2CH2NH2·3H2O, Cu2(C2O4)2·5HOCH2CH2NH2, Zn2(C2O4)2·5HOCH2CH2NH2·2H2O and Cd2(C2O4)2·HOCH2CH2NH2·2H2O. Following the reaction ofM(II) oxalate with 2-ethanolamine in the presence of ethanolammonium oxalate, a compound with the empirical formula ZnC2O4·HOCH2CH2NH2·2H2O1 was isolated. The complexes were identified by using elemental analysis, X-ray powder diffraction patterns, IR spectra, and thermogravimetric and differential thermal analysis. The IR spectra and X-ray powder diffraction patterns showed that the complexes obtained were not isostructural. Their thermal decompositions, in the temperature interval between 20 and about 900°C, also take place in different ways, mainly through the formation of different amine complexes. The DTA curves exhibit a number of thermal effects. 相似文献
4.
V. A. Samsonov 《Russian Chemical Bulletin》2007,56(12):2510-2512
Heating of benzofurazans with ethanolamine in the presence of catalytic amount of p-toluenesulfonic acid leads to quinoxalines.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2424–2425, December, 2007. 相似文献
5.
Hatsuhiko Harashina Toshio Nakane Takahito Itoh 《Journal of polymer science. Part A, Polymer chemistry》2007,45(11):2184-2193
Semiaromatic poly(ester amide)s (PEAs) were synthesized by the melt polycondensation of ethanolamine (EA) derivatives with dimethyl terephthalate and ethylene glycol in the presence of tetrabutyl titanate as a catalyst, and their crystallization and thermal properties were investigated. The introduction of an amide group into a semiaromatic polyester such as poly(ethylene terephthalate) (PET) produced PEAs (EA-modified PET polymers) with an increase in the melting point. However, these PEAs were found to decompose at a lower temperature than PET on the basis of TGA. Moreover, direct pyrolysis/mass spectrometry measurements suggested that an initial step of the thermal decomposition was a β-CH hydrogen-transfer reaction via asix-member ring transition state at the ester–ethylene–amide unit, at which carbon–oxygen bond scission took place to yield carboxyl and N-vinylamide end groups. Furthermore, molecular orbital calculations using trimer models bis[2-[[4-(methoxycarbonyl)benzoyl]oxy]ethyl]terephthalate, N-[2-[[4-(methoxycarbonyl)benzoyl]oxy]ethyl]-4-[2-[[4-(methoxycarbonyl)benzoyl]oxy]ethyloxycarbonyl]benzamide, and N,N′-bis[2-[[4-(methoxycarbonyl)benzoyl]oxy]ethyl]terephthalamide strongly supported the idea that the β-CH hydrogen-transfer reaction in the thermal decomposition of PEAs might occur more easily at the methylene group next to the amide group in an ester–ethylene–amide unit rather than at the methylene group next to the ester group in an ester–ethylene–ester unit. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 2184–2193, 2007 相似文献
6.
Direct Participation of a Peripheral Side Chain of a Corrin Ring in Coenzyme B12 Catalysis
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Dr. Naoki Shibata Yui Sueyoshi Prof. Dr. Yoshiki Higuchi Prof. Dr. Tetsuo Toraya 《Angewandte Chemie (International ed. in English)》2018,57(26):7830-7835
The crystal structures of the B12‐dependent isomerases (eliminating) diol dehydratase and ethanolamine ammonia‐lyase complexed with adenosylcobalamin were solved with and without substrates. The structures revealed that the peripheral a‐acetamide side chain of the corrin ring directly interacts with the adenosyl group to maintain the group in the catalytic position, and that this side chain swings between the original and catalytic positions in a synchronized manner with the radical shuttling between the coenzyme and substrate/product. Mutations involving key residues that cooperatively participate in the positioning of the adenosyl group, directly or indirectly through the interaction with the a‐side chain, decreased the turnover rate and increased the relative rate of irreversible inactivation caused by undesirable side reactions. These findings guide the engineering of enzymes for improved catalysis and producing useful chemicals by utilizing the high reactivity of radical species. 相似文献
7.
Shift reagents in ion mobility spectrometry: the effect of the number of interaction sites,size and interaction energies on the mobilities of valinol and ethanolamine
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Roberto Fernández‐Maestre Dairo Meza‐Morelos Ching Wu 《Journal of mass spectrometry : JMS》2016,51(5):378-383
Overlapping peaks interfere in ion mobility spectrometry (IMS), but they are separated introducing mobility shift reagents (SR) in the buffer gas forming adducts with different collision cross‐sections (size). IMS separations using SR depend on the ion mobility shifts which are governed by adduct's size and interaction energies (stabilities). Mobility shifts of valinol and ethanolamine ions were measured by electrospray‐ionization ion mobility‐mass spectrometry (MS). Methyl‐chloro propionate (M) was used as SR; 2‐butanol (B) and nitrobenzene (N) were used for comparison. Density functional theory was used for calculations. B produced the smallest mobility shifts because of its small size. M and N have two strong interaction sites (oxygen atoms) and similar molecular mass, and they should produce similar shifts. For both ethanolamine and valinol ions, stabilities were larger for N adducts than those of M. With ethanolamine, M produced a 68% shift, large compared to that using N, 61%, because M has a third weak interaction site on the chlorine atom and, therefore, M has more interaction possibilities than N. This third site overrode the oxygen atoms' interaction energy that favored the adduction of ethanolamine with N over that with M. On the contrary, with valinol mobility shifts were larger with N than with M (21 vs 18%) because interaction energy favored even more adduction of valinol with N than with M; that is, the interaction energy difference between adducts of valinol with M and N was larger than that between those adducts with ethanolamine, and the third M interaction could not override this larger difference. Mobility shifts were explained based on the number of SR's interaction sites, size of ions and SR, and SR–ion interaction energies. This is the first time that the number of interaction sites is used to explain mobility shifts in SR‐assisted IMS. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
8.
Glutaryl-7-aminocephalosporanic acid (GL-7-ACA) acylase isan enzyme that converts GL-7-ACA to 7-aminocephalosporanic acid,
a starting material for semisynthetic cephalosporin antibiotics. In this study, optimal conditions for the immobilization
of GL-7-ACA acylase were determined by experimental observations and statistical methods. The optimal conditions were as follows:
1.1 M phosphate buffer (pH 8.3) as buffer solution, immobilization temperature of 20°C, and immobilization time of 120 min. Unreacted
aldehydegroups were quenched by reaction with a low-molecular-weight material such as l-lysine, glycine, and ethanolamine after immobilization in order to enhance the activity of immobilized GL-7-ACA acylase.
The activities of immobilized GL-7-ACA acylase obtained by using the low-molecular-weight materials were higher than those
obtained by immobilized GL-7-ACA acylase not treated with low-molecular-weight materials. In particular, the highest activity
of immobilized GL-7-ACA acylase was obtained using 0.4% (v/v) ethanolamine. We also investigated the effect of sodium cyanoborohydride
in order to increase the stability of the linkage between the enzyme and the support. The effect on operational stability
was obvious: the activity of immobilized GL-7-ACA acylase treated with 4% (w/w) sodium cyanoborohydride remained almost 100%
after 20 times of reuse. 相似文献
9.
Numerous drugs are carboxylic acid derivatives containing amino group, and hydrolysis reaction of these agents often generates toxic amines. Thus, the detection of amine impurity is of great importance in drug quality control of these amino group-containing ester and amide. A capillary electrophoresis method coupled with end-column electrochemiluminescent detection based on tris(2,2′-bipyridyl)ruthenium(II) system was proposed for the analysis of N,N-dimethyl ethanolamine (DMEA, the degradation product of meclophenoxate) in the presence of its precursor. Baseline separation of DMEA and meclophenoxate can be easily achieved under the selected conditions. DMEA can be assayed within 3 min over the concentration range of 5.0 × 10−8 to 3.0 × 10−6 mol L−1 with a detection limit of 2.0 × 10−8 mol L−1 at the signal-to-noise ratio of 3. The relative standard deviations of the signal intensity and the migration time were less than 5.3 and 2.5% for a standard sample containing 1.0 × 10−7 mol L−1 DMEA (n = 5), respectively. The presented method has been successfully applied for the profiling of DMEA resulting from the hydrolysis of meclophenoxate in commercial formulations. A primary stability investigation of meclophenoxate in aqueous solution was also carried out at different temperatures, and the results showed that the degradation of meclophenoxate accelerated at the higher temperature. 相似文献
10.