Synthesis of 4-arylmorpholine -2,3-diones by the reaction of n-(2-hydroxyethyl)arylamines with diethyl oxalate

The corresponding 4-arylmorpholine-2,3-diones were obtained by the reaction of N-(2-hydroxyethyl)aniline, N-(2-hydroxypropyl)aniline, N-(2-hydroxyethyl)-p-chloroaniline, and N-(2-hydroxyethyl)-p-anisidine with diethyl oxalate. The N-(2-hydroxyethyl)-o-, p-, and m-toluidines and N-(2-hydroxyethyl)-o-anisidine form 1,4-(ditolyl)piperazines and 1,4-di(o-anisyl)piperazine.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 22–24, January, 1971.     

Saturated Nitrogen-containing Heterocycles. 20. Catalytic Reduction of N-Hydroxyethylpyridinium and Quinolinium Salts

Previously unknown N-(2-hydroxyethyl)perhydroquinolines and N-(2-hydroxyethyl)piperidines were synthesized by catalytic reduction of N-(2-hydroxyethyl)tetrahydroquinolinium and N-(2-hydroxyethyl)tetrahydropyridinium tetrafluoroborates. A scheme for the formation of the hydrogenation products is presented.     

一种结构新颖的螺锗化合物的合成

在吡啶存在下，本文利用手性配体试剂L-N，N-双(2-羟乙基)苏氨酸(1)与β-羧基乙基锗倍半氧化物(2)反应，首次得到一种具有旋光性、含δ-内酯环新颖结构的螺锗化合物(3)。^1H NMR ，IR和MS的测定数据均表明NGe配键是存在的。     

X-ray absorption near edge structure as a source of structural information

N-(2-Hydroxyethyl)-β-alaninatonickel(II) was synthesized by the interaction of basic nickel carbonate with N-(2-hydroxyethyl)-β-alanine. The structures of the chelating agent and its nickel complex were studied by single crystal X-ray diffraction. In the synthesized compound, the nickel ion lies at the center of an octahedron of the N and 2O donor atoms of two tridentate ligands, each ligand having a meridional conformation. The ligands around the central atom are arranged in perpendicular planes. This coordination of two ligands yields two stereoisomers, whose cocrystallization affords a racemate.     

New radiopharmaceuticals based on N-substitution of nitrilotriacetic acid

In this paper, the labeling characteristics and biological behavior of five aminopolycarboxylic acid derivatives have been studied: N-(phosphonomethyl) nitrilodiacetic acid (^99mTc-MPIDA), N,N-(diphosphono) aminoacetic acid (^99mTc-GDP), N-(2-carbamoylethyl) nitrilodiacetic acid (^99mTc-KEIDA), N-(2,3-dihydroxypropyl) nitrilodiacetic acid (^99mTc-DPKA), 2-[N-(2-hydroxyethyl)-N-carboxymethyl] aminopropanoic acid (^99mTc-EAPA).     

合成固载希夫碱配合物作为配体交换材料

Two new sporopollenin-immobilized Schiff bases, S-[N-(2-aminoetil) salicylaldiimino] and S-[N-(2-aminoetil) benzaldiimino], and their cobalt (Ⅲ) and nickel (Ⅱ) complexes, S-[N-(2-aminoetil) benzaldiimino] aquatriacetato cobalt (Ⅲ), S-[N-(2-aminoetil) salicylaldiimino] aquadiacetato cobalt (Ⅲ), S-[N-(2-aminoetil) benzaldiimino] diacetato nickel (Ⅱ), and S-[N-(2-aminoetil) salicylaldiimino] diacetato nickel (Ⅱ), were synthesized onto a chemically modified sporopollenin with ethylenediamine. The immobilized ligands and their metal complexes were characterized by thermal analysis and spectroscopic techniques such as infrared, ultraviolet-visible, and atomic absorption spectrometry. Immobilized Schiff base metal complexes, S-[N-(2-aminoetil) benzaldiimino] aquatriacetato cobalt (Ⅲ) and S-[N-(2-aminoetil) salicylaldiimino] aquadiacetato cobalt (Ⅲ), were used as ligand exchanger media to investigate ligand adsorption behavior of methylene blue (MB) with column technique. The result shows that the chelation of methylene blue with S-[N-(2-aminoetil) salicylaldiimino] aquadiacetato cobalt (Ⅲ) complex increases ligand adsorption capacity.     

5-(N-2-羟乙基)羟乙酰氨基-N,N'-双(2,3-二羟丙基)-2,4,6-三碘-1,3-苯二甲酰胺的合成

5-氨基-N,N'-双(2,3-二羟丙基)-2,4,6-三碘-1,3-苯二甲酰胺(2)在N,N-二甲基乙酰胺中可直接与乙酰氧基乙酰氯反应,产物再经碱性水解得5-羟乙酰氨基-N,N'-双(2,3-二羟丙基)-2,4,6-三碘-1,3-苯二甲酰胺(3),后者再与氯乙醇反应生成5-(N-2-羟乙基)羟乙酰胺基-N,N'-双(2,3-二羟丙基)-2,4,6-三碘-1,3-苯二甲酰胺(1),经乙二醇甲醚/正丁醇重结晶,纯度高于99%(HPLC),反应总收率由39.3%(文献值)提高到55.1%.     

Functionalization of a polyaspartamide with glycidyl methacrylate: A useful method to prepare hydrogels through gamma irradiation

α,β-Poly(N-2-hydroxyethyl)-DL-aspartamide (PHEA) was derivatized with glycidyl methacrylate (GMA). Aqueous solutions of the obtained copolymer PHEA-GMA (PHG) were irradiated by gamma rays with a dose rate of 0.5 KGy/h and at zero°C in the presence or in the absence of N, N'-methylenebisacrylamide (BIS). New hydrogel systems were obtained and characterized by FT-IR analyses and swelling measurements in aqueous medium at different pH values.     

Biosynthesis of vitamin B1 in yeast. Derivation of the pyrimidine unit from pyridoxine and histidine. Intermediacy of urocanic acid

Incorporation studies with 13C-, 15N-, and 2H-labeled substrates, followed by NMR analysis, show that the pyrimidine unit of thiamin (Vitamin B1) originates from a C5N fragment, derived from C-2',2,N,C-6,5,5' of pyridoxol (Vitamin B6) and an N-C-N fragment derived from L-histidine. Urocanic acid serves as an intermediate on the route of the N-C-N fragment of histidine into the thiamin pyrimidine.     

Electrophoretic determination of calystegines A3 and B2 in potato

Potatoes, members of the Solanaceae plant family, contain calystegines, water-soluble nortropane alkaloids, which are biologically active as glycosidase inhibitors. The content of calystegines A(3) and B(2) in different varieties of potato and in various parts of the tubers (whole potato, peel, flesh, and sprouts) were analysed by new capillary zone electrophoresis and capillary isotachophoresis methods and by the routine GC method. The optimized background electrolyte for capillary zone electrophoretic analysis was mixture of 20 mM histidine, 20 mM N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonic acid and 20% (v/v) methanol in demineralized water. Calystegines were detected by indirect UV detection at 210 nm. A clear separation of calystegines from other components of the methanolic sample extract was achieved within 4 min. The electrolytes for isotachophoretic analysis consisted of 5 mM NH(4)OH, 10 mM N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonic acid, 0.1% hydroxyethylcellulose and 20% (v/v) methanol in demineralized water (leading) and 5 mM histidine+10 mM acetic acid+20% (v/v) methanol in demineralized water (terminating). Calystegines were separated within 20 min and detected by a conductimeter. Method characteristics of both zone electrophoresis and isotachophoresis, i.e., linearity (10-100 ng/microl and 1-10 ng/microl), accuracy (recovery 96+/-5% and 98+/-4%), intra-assay repeatability (4.2% and 3.5%), and detection limit (3 and 0.4 ng/microl) were evaluated. Simple sample preparation, sufficient sensitivity, speed of analysis, and low running cost are important attributes of the electrophoretic methods. The overall results of electrophoretic methods were comparable with GC.     

Reaction of 2-Chloro-5-(chloromethyl)thiophene with Monoethanolamine Vinyl Ether

At the alkylation of monoethanolamine vinyl ether with 2-chloro-5-(chloromethyl)thiophene in ethyl alcohol (60-70°C) a product of disubstitution and transvinylation, viz. N,N-bis(5-chloro-2-thienylmethyl)-N-(2-hydroxyethyl)ammonium chloride is formed. The analogous reaction in the absence of solvent proceeds with the formation of N-(5-chloro-2-thienylmethyl)-N-(2-vinyloxyethyl)amine.     

Synthesis and Properties of N-(2,2,2-Trichloroethyl)-2-thiophenesulfonamides

Chlorination of 2-thiophenesulfonamide gave unstable N,N-dichloro-2-thiophenesulfonamide which was brought into reactions with 1,2-polyhaloethenes. The condensation of 2-thiophenesulfonamide with trichloroacetaldehyde afforded N-(2,2,2-trichloro-1-hydroxyethyl)-2-thiophenesulfonamide which reacted with benzene, toluene, 2-chlorothiophene, and phenol to form the corresponding N-(1-aryl-2,2,2-trichloroethyl)-2-thiophenesulfonamides. Under more severe conditions, the latter were converted into 1,1-diaryl-2,2,2-trichloroethanes. The reaction of N-(2,2,2-trichloro-1-hydroxyethyl)-2-thiophenesulfonamide with substituted arenes, including phenol, was regioselective: only the corresponding para-substituted products were obtained. Hydrolysis of N-[2,2,2-trichloro-1-(4-tolyl)ethyl]-2-thiophenesulfonamide yielded N-(2-thienylsulfonyl)-2-(4-tolyl)glycine.     

Kinetics and mechanism of diethanolamine degradation in aqueous solutions containing carbon dioxide

The problem of diethanolamine (DEA) degradation in gas-treating processes was quantified through a detailed kinetic study. This reaction was found to be catalyzed by CO₂, and degradation occurs in a successive manner to 3-(2-hydroxyethyl)oxazolidone-2, to N,N,N′-tris(2-hydroxyethyl)ethylenediamine and then to N,N′-bis(2-hydroxyethyl)piperazine. A reaction mechanism consistent with these observations was proposed and tested through kinetic analyses. A satisfactory kinetic model which can be of practical use was derived.     

氮氧杂链型配体合成与Cu(Ⅱ)和Zn(Ⅱ)配位性质研究

合成了4种氮氧杂链型配体N,N'-二-(2-羟乙基)-乙二胺(L¹)、N-(2-羟基苄基)-丙醇胺(HL²)、N-(2-羟乙基)-N'-(2-羟基苄基)-乙二胺(HL³)和N-(2-羟乙基)-二乙三胺-(L⁴),通过元素分析、IR和¹H NMR等手段表征了其结构,用pH电位滴定法在25℃、I=0.10(KNO₃)条件下,测定了L¹和HL²与Cu(Ⅱ)离子以及HL³和L⁴与Zn(Ⅱ)离子配位平衡常数.结果表明:L¹和HL²与Cu(Ⅱ)离子配位时,均可生成四配位配合物,其中第三配位点醇羟基配位较强,其质子离解常数pK_a1分别为7.28和7.32;第四配位点是第2个醇羟基或1个水分子配位,其pK_a2分别为9.33和9.04;HL³和L⁴与Zn(Ⅱ)均可生成五配位配合物,第四配位点均为醇羟基,其离解常数pK_a1分别为7.76和7.96,第五配位点均为H₂O,其pK_a2分别为9.47和9.57.从上述热力学结果可见,配合物在中性pH值范围能生成亲核试剂Cu(Ⅱ)…^-OR或Zn(Ⅱ)…^-OR,而且均具备双重催化酯类底物水解的条件.     

Study of Cyclization of Chelating Compounds Using Electrospray Ionization Mass Spectrometry

Electrospray ionization mass spectrometry (ESI-MS) was used for the study of cyclization of organic chelating compounds (chelators). Four chelating compounds were studed: Symmetrical ethylenediaminediacetic acid (s-EDDA), Unsymmetrical ethylenediaminediacetic acid (u-EDDA), N-(2-hydroxyethyl) ethylenediaminetriacetic acid (HEDTA), and N-(2-hydroxyethyl)iminodiacetic acid (HEIDA). The chelators were cyclized with treatments of acids and heating. The open and cyclized form of the chelators were semi-quantified by both positive and negative ion modes ESI-MS. The kinetics of chelator cyclization was studied as a function of reaction temperature and the pH of the matrix. The cyclization of s-EDDA was found to be a pseudo-first order reaction in s-EDDA and overall second order. The cyclizations of HEIDA and HEDTA are reversible reactions. Higher temperature and lower pH favors cyclization.     

氨基酸衍生物PMV，PML和PMA的电喷雾质谱研究

应用电喷雾（ESI）质谱及其多级串联质谱（MS~n）技术研究了三个氨基酸衍 生物N-(N-亚甲基-2-吡咯烷酮）-缬氨酸（PMV），N，N-二-（N-亚甲基-2-吡咯烷 酮）-亮氨酸（PML）和N，N-二-（N-亚甲基-2-吡咯烷酮）-β-丙氨酸（PMA）在电 喷雾条件下的质谱行为。在此条件下三个氨基酸衍生物PMV，PML和PMA可以质子化 形式PMVH~+，PMLH~+和PMAH~+存在，并且检测到它们的Na~+和K~+的加合物。在电 喷雾条件下PMV，PML和PMA优先采取C-N键的断裂，并且通过分子间的氢键作用形成 了许多二聚和三聚物种。     

Reaction of hydroxy derivatives of piperidines and pyridines with acetylene under pressure

Methods for the synthesis of vinyl ethers of N-(β-hydroxyethyl)-piperidine, 3-hydroxy-N-methylpiperidine, 2-(β-hydroxyethyl)pyridine, and 2-(hydroxypyridine) based on the addition of the corresponding derivatives to acetylene have been developed. Their hydrogenation forms the corresponding ethyl ethers.     

A New Perspective of Enthalpies of Proton Transfer of Aliphatic Amines, Hydroxyamines, and Aminoalkylsulfonic Acids in Methanol–Water Mixtures by Direct Calorimetry

The enthalpies of proton transfer in methanol–water mixtures (0–90 wt.% methanol) of the aliphatic amines: triethylamine (Et₃N), t-butylamine, and quinuclidine (Q); the hydroxyamines:2-amino-2-methyl-1-propanol (Amp), 2-amino-2-methyl-1,3-propanediol (Bis), tris(hydroxymethyl)-aminomethane (Tris), and 2,2-bis(hydroxymethyl)-2,2′,2′′-nitrilotriethanol (Bis-Tris); and the aminoalkylsulfonic acids: 3-(N-morpholino)-propanesulfonic acid (MOPS), N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonic acid (Bes), and N-(2-hydroxyethyl)piperazine-N′-2-ethanesulfonic acid (HEPES), have been measured by direct calorimetry at 25°C. The results of the protonation reactions have been reported. All the salient features are now examined together with a view to assessing the success of interpretations using classical electrostatic formulation and three-dimensional structures in methanol–water mixtures. The objective is to find answers to the complex phenomena of solvation.     

Copper(II) binding by fragments of alpha-synuclein containing M1-D2- and -H50-residues; a combined potentiometric and spectroscopic study

Stability constants and ligand donor sets of the copper(II) complexes of the NH2-29-56(L1)(AA30GKTKEGVLYV40GSKTKEGVVH50GVATVA56-NH2), NH2-M29-D30-56(L2) and Ac-M29-D30-56(L3) fragments of alpha-synuclein were determined in aqueous solution for 1 : 1 metal-to-ligand molar ratio in the pH range 2.5-10.5. The tyrosine residue in the 39th position of the alpha-synuclein fragments does not take part in the coordination of the metal ion. The potentiometric and spectroscopic data (UV-Vis, CD, EPR) show that acetylation of the amino terminal group induces significant changes in the coordination properties of the L3 fragment compared to that of the L2 peptide. When the amino group is blocked (L3) the imidazole nitrogen of the histidine residue acts as an anchoring site and at higher pH the 3N {N(Im),2N-} and 4N {N(Im),3N-} complexes are formed. The L1 peptide at physiological pH forms in equilibrium 3N {NH2,N-,CO,N(Im)} and 4N {NH2,2N-,N(Im)} complexes. For the L2 peptide the coordination of the copper(II) ions starts from the N-terminal Met residue and with increasing of pH the Asp residue in second position of amino acid sequence coordinates and stabilizes significantly the 2N complex as a result of chelation through the beta-carboxylate group. At physiological pH the 3N {NH2,N-,beta-COO-,N(Im)} coordination mode dominates. At pH above 6 the results for the L2 fragment suggest the formation of 3N and 4N complexes (in equatorial plane) and the involvement of the lateral NH2 group of Lys residue in the axial coordination of Cu(II) ion. In CD spectra sigma (epsilon-NH2-Lys) --> Cu(II) charge transfer transition is observed. The stability constants for the L2 fragment of alpha-synuclein of the 4N {NH2,2N-,N(Im)} and {NH2,3N-} complexes are higher about 1.5 and 0.7 orders of magnitude, respectively, by comparison to those of the L1 peptide. This increase may be explained by the involvement of the epsilon-NH2 group of Lys residue in the coordination sphere of metal ion.     

Synthesis and DNA cleavage activity of artificial receptor 1,4,7-triazacyclononane containing guanidinoethyl and hydroxyethyl side arms

A novel phosphodiester receptor 1-(2-guanidinoethyl)-4-(2-hydroxyethyl)-1,4,7-triazacyclononane hydrochloride 1 was synthesized. DNA cleavage efficiency of 1 exhibits remarkable increases compared with its ZnII complex and corresponding nonguanidinium compound N-(2-hydroxyethyl)-1,4,7-triazacyclononane and parent 1,4,7-triazacyclononane. Kinetic data of DNA cleavage promoted by 1 fit to a Michaelis-Menten-type equation with kmax of 0.160 h-1 giving 107-fold rate acceleration over uncatalyzed DNA. The acceleration is driven by the spatial proximity of the nucleophilic hydroxyl group and the electrophilic activation for the phosphodiester by the guanidinium group.