Regeneration of 2-amino-2-methyl-1-propanol used for carbon dioxide absorption

To improve the efficiency of the carbon dioxide cycling process and to reduce the regeneration energy consumption, a sterically hindered amine of 2-amino-2-methyl-1- propranol （AMP） was investigated to determine its regeneration behavior as a CO2 absorbent. The CO2 absorption and amine regeneration characteristics were experimentally examined under various operating conditions. The regeneration efficiency increased from 86.2% to 98.3% during the temperature range of 358 to 403 K. The most suitable regeneration temperature for AMP was 383 K, in this experiment condition, and the regeneration efficiency of absorption/regeneration runs descended from 98.3% to 94.0%. A number of heat-stable salts （HSS） could cause a reduction in CO2 absorption capacity and regeneration efficiency. The results indicated that aqueous AMP was easier to regenerate with less loss of absorption capacity than other amines, such as, monoethanolamine （MEA）, diethanolamine （DEA）, diethylenetriamine （DETA）, and N-methyldiethanolamine （MDEA）.

Microwave-assisted reactions:Three-component process for the synthesis of 2-amino-2-chromenes under microwave heating

2-Amino-2-chromenes are class of heterocycles that posses considerable interest as pigments, cosmetics, potential agrochemicals and being the main constituents of many natural products. Although, they are generally prepared either under conventional heating, benign reagents or very recently, a three component condensation in polyethylene glycol-water in the presence of nanosized magnesium oxide, most of these methods require prolonged reaction time, reagents in stoichiometric amounts and generate moderate yields of products. Microwave technique performs a better yield in a short reaction time （85-94%; 5-8 min）. Also, three-component one step reaction is of great interest for cost savings from the point of raw materials, energy and time, A combination between both techniques will be attractive for researchers in that field.

Synthesis and Structural Characterization of a Tetranuclear Copper Complex with 2-Amino-1,3-thiazole

The title tetranuclear complex,（μ4-oxo）-hexakis（μ2-chloro）-tetrakis（2-amino-1,3-thiazole-N）-tetra-copper（ii） [Cu4（μ4-O）（μ-Cl）6L4]（1,L=2-amino-1,3-thiazole） was synthesized by the reaction of CuCl2·2H2O with 2-amino-1,3-thiazole in methanol and characterized by IR spectra and X-ray diffraction.Complex 1 crystallizes in triclinic,space group P1 with a=9.7137（2）,b=10.7005（2）,c=14.6505（2）,α=83.9550（10）,β=82.0930（10）,γ=67.1640（10）°,V=1387.84（4）3,Mr=883.43,Z=2,μ=3.927 mm-1,Dc=2.1144 g/cm3,F（000）=868,R=0.0332 and wR=0.0814.The complex contains a tetrahedron of four CuII atoms coordinating to a central μ4-O atom,with the six edges of the tetrahedron bridged by six Cl atoms.The Cu-O bond distances range from 1.910（2） to 1.918（2）,Cu-Cl from 2.3501（11） to 2.5924（10）,and Cu-Cu from 3.1003（6） to 3.1663（6）.The coordination geometries of the four coppers distort from trigonal bipramid to tetragonal pyramid with different distortion factors.The free animo groups of the ligands result in a lot of N-H···Cl and N-H···N intra-and intermolecular hydrogen bonds.

Crystal Structures of 2-Aminobenzothiazole-based Inhibitors in Complexes with Urokinase-type Plasminogen Activator

Urokinase-type plasminogen activator （uPA） plays a crucial role in the regulation of plasminogen activation, tumor cell adhesion and migration. The inhibition of uPA activity is a promising mechanism for anti-cancer therapy. Most current uPA inhibitors employ a highly basic group （either amidine or guanidine group） to target the S1 pocket of uPA active site, which leads to poor oral bioavailability. Here we study the possibility of using less basic 2-aminobenzothiazole （ABT） as S1 pocket binding group. We report the crystal structures of uPA complexes with ABT or 2-amino-benzothiazole-6-carboxylic acid ethyl ester （ABTCE）. The inhibitory constants of these two inhibitors were measured by a chromogenic competitive assay, and it was found that ABTCE is a better inhibitor for uPA （Ki = 656 μM） than ABT （Ki = 5.03 mM）. This work shows that 2-amniobenzothiazole can be used as P1 group which may have better oral bioavailability than the commonly used amidine or guanidine group. We also found the ethyl ester group occupies the characteristic oxyanion hole and contacts to uPA 37- and 60-loops. Such work provides structural information for further improvements of potency and selectivity of this new class of uPA inhibitor.

An Efficient and Rapid Synthesis of 2-amino-4-arylthiazoles Employing Microwave Irradiation in Water

A facile, high yielding green chemical synthetic protocol adaptable to the parallel synthesis of a library of potentially bioactive 2-amino-4-arylthiazoles is reported herein. The methodology involves the condensation of various aracyl bromides with N-arylthioureas under MWI using water as solvent, to yield pure products (81%-97%) in very short reaction times (1-20 min).

豹皮菌中2-Amino-3-(1,2-dicarboxyethylthio)propanoic acid非对映异构体的绝对构型

豹皮菌中２Ａｍｉｎｏ３（１，２ｄｉｃａｒｂｏｘｙｅｔｈｙｌｔｈｉｏ）ｐｒｏｐａｎｏｉｃａｃｉｄ非对映异构体的绝对构型顾谦群伏谷真二野副重男（青岛海洋大学海洋药物与食品研究所，青岛２６６００３；东北大学药学部，日本仙台）豹皮菌（Ａｍａｎｉ...

Preparation and Standard Formation Enthalpy of 2-Amino-4,6-dimethylpyrimidine and Its Related Complexes of Copper

The complexes of hydrous copper chloride and copper nitrate with 2-amino-4,6-dimethylpyrimidine(ADMP) were prepared via reflux in alcohol. The compositions of the complexes were identified as Cu(ADMP) 2Cl 2·2H 2O(b) and Cu(ADMP)(NO 3) 2·H 2O(c) by chemical and elemental analyses. The complexes were characterized by IR, XPS, 1H NMR and TG-DTG techniques. The constant-volume combustion energies of ADMP and the complexes, Δ c E , were determined by a precise rotating-bomb calorimeter at 298 15 K. They were (-3664 53±1 18), (-4978 47±2 72) and (-1696 70±1 36) kJ/mol, respectively. Their standard enthalpies of combustion, Δ c H 0 m, and standard enthalpies of formation, Δ f H 0 m, were calculated to be (-3666 39±1 18), (-4977 23±2 72), (-1691 12±1 36) kJ/mol and (19 09±1 43), (-2041 80±3 29), (-2397 24±1 65) kJ/mol, respectively.

Synthesis and Cytotoxicity of Novel Diaryl Ureas Containing 2-Amino-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidinyl Group

A series of 2-amino-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidinyl substituted diaryl urea derivatives was designed and synthesized. Their in vitro cytotoxicities against two cancer cell lines（Bel-7402 and A549） were evaluated by standard MTT assay. Six of tested compounds 6, 8, 10, 17, 21 and 22 exhibited more potent cytotoxicity superior to sorafenib. The structure activity relationship（SAR） study indicates that 2-amino-5,6,7,8-tetrahydropyrido- [4,3-d]pyrimidinyl group was an option for cytotoxic potency.

Synthesis of 2-Amino-4,6-dimethoxypyrimidine(ADM)

Using malononitrile as the raw material, a novel synthesis route of 2-amino-4,6-dimethoxypyrimidine(ADM) was put forward, in order to solve the instability in first step reaction of industrial synthesis. The influence of reactant ratio, temperature and time on product quality and yield was explored. The results showed that ADM was successfully prepared through acetyl chloride route, the yield was higher than that of industrial production process, and the process stability was good, with the product purity over 99%. Therefore, the new synthesis route is suitable for industrial production.

Synthesis and Crystal Structure Analysis of 2-Amino-4,6-bis(diphenoxyl phosphoramide)-1,3,5-triazine

A disubstituted triazine compound, namely, 2-amino-4,6-bis（diphenoxyl phosphorramide）-1,3,5-triazine, which is an inherent flame retardant monomer, was synthesized specifically, and its structure was characterized by using NMR spectrum and X-ray single-crystal diffraction. Unit cell parameters： space group P21/c, Z=4, a=8.7494（15）, b=27.518（5）, c=12.511（2）,β=109.323（16） , Z=4, V=2842.7（9）β3 , Dc=1.380 g/cm3 , F（000）=1224 and Mr=590.46. All the atoms are in the general positions.

Spectroscopic Characterization, Molecular Modeling and DFT/TD-DFT/PCM Calculations of Novel Hydrogen-Bonded Charge Transfer Complex between Chloranilic Acid and 2-Amino-4,6-Dimethylpyridine

A charge transfer hydrogen bonded complex between the electron donor (proton acceptor) 2-amino-4,6-dimethylpyridine with the electron acceptor (proton donor) chloranilic acid has been synthesized and studied experimentally and theoretically. The stability constant recorded high values indicating the high stability of the formed complex. In chloroform, ethanol, methanol and acetonitrile were found the stoichiometric ratio 1:1. The solid complex was prepared and characterized by different spectroscopy techniques. FTIR, 1H and 13C NMR studies supported the presence of proton and charge transfers in the formed complex. Complemented with experimental results, molecular modelling using the density functional theory (DFT) calculations was carried out in the gas, chloroform and methanol phases where the existence of charge and hydrogen transfers. Finally, a good consistency between experimental and theoretical calculations was found confirming that the applied basis set is the suitable one for the system under investigation.

Theoretical Study on the Reaction Mechanism of 2-Methoxybenzaldehyde,4-Bromo-indanone,Malononitrile and Ammonium Acetate One-pot to Form 6-(2-Methoxyphenyl)-2-amino-6-bromo-5H-indeno[1,2-b]pyridine-3-carbonitrile

The reaction mechanism of 2-methoxybenzaldehyde, 4-bromo-indanone, malononitrile and ammonium acetate one-pot to form 6-（2-methoxyphenyl）-2-amino-6-bromo-5 Hindeno[1,2-b]pyridine-3-carbonitrile was studied by density functional theory. The geometries of the reactants, transition states, intermediates and products were optimized at the PW91/DNP level. Vibration analysis was carried out to confirm the transition state structure. Reaction pathways were investigated in this study. The result indicates that the reaction Re→ TSB1→IMB1→ TSB2→ IMB2→TSB3→IMB3→TSB4→IMB4→TSB5→IMB5→TSB6→IMB6→TSB7→IMB7→ TSB8→IMB8→TSB9→IMB9→P2 is the main pathway, the activation energy of which is the lowest. The dominant product predicted theoretically is in agreement with the experiment results.

Synthesis and Evaluation of 2-Amino-4H-Pyran-3-Carbonitrile Derivatives as Antitubercular Agents

A series of 2-amino-4H-pyran-3-carbonitrile derivatives were designed and synthesized. Their antitubercular activities were evaluated against autoluminescent M. tuberculosis H37Ra and standard strain M. tuberculosis H37Rv. No obvious antitubercular activities could be observed (MIC > 10 ug/mL). The results are in sharp contrast with the previously reported data.

A Facile Synthesis of 2-Amino-5-Cyano-4, 6-Disubstitutedpyrimidines under MWI

Microwave Assisted Organic Synthesis (MAOS) is energy efficient and effective tool to speed up the synthesis for drug discovery process. In the present study we report a novel protocol for the rapid, high throughput synthesis of mononuclear 2-amino-5-cyano-4,6-disubstituted pyrimidines, adaptable to parallel synthesis for compound libraries. The overall reaction time in hrs has been reduced to 25 - 50 minutes with improved yields.

Syntheses of Coordination Compounds of 2-Amino-3-Methylbutanoic Acid Their Mixed Ligand Complexes and Antibacterial Activities

Coordination compounds of 2-amino-3-methylbutanoic acid were synthesized with chromium(III) and oxovanadium(IV) ions. M:L;1:2. Adducts of these complexes using 1,10-phenantroline and ethylenediamine were further synthesized, M:L, (1:2). These compounds were characterized using electronic, infra-red spectrophotometry, magnetic susceptibility measurement and percentage metal analyses. The zones of inhibition and minimum inhibitory concentrations of the compounds against eight microbes were studied. The results obtained indicated an octahedral geometry for the Cr(III) complexes, indicative of additional coordination of two water molecules. On the other hand a square pyramid geometry was obtained for the binary oxovanadium complex and its 1,10-phenantroline adduct. However, for the oxovanadium ethylenediamine adduct a distorted octahedral geometry was proposed. The result for the antibacterial studies indicated that both mixed ligand complexes of 1,10-phenantroline exhibited good antibacterial activity, and in some cases better activity than the standard, streptomycin.

Palladium-Catalyzed Sonogashira Coupling Reaction of 2-Amino-3-Bromopyridines with Terminal Alkynes

Palladium-catalyzed the Sonogashira coupling reaction of 3-halogen-2-aminopyridines 1 with terminal alkynes 2 afforded the corresponding 21 target products 3a-3u in the presence of palladium catalyst. The structure of target products 3a-3u was confirmed and characterized by 1H NMR, 13C NMR, and HRMS. The influences of different kinds of catalyst loading, bases, substrates and temperature were also investigated. Under the optimized conditions, including 2.5 mol% Pd?(CF3COO)2, 5 mol% PPh3 and 5 mol% CuI as additive, 1 mL Et3N, substrate 1 with terminal alkynes 2 for the cross-coupling reactions at 100°C for 3 h in DMF afforded the corresponding products of 2-amino-3-alkynylpyridines 3 in moderate to excellent yields (72%?-?96%). The present methodology has provided an effective synthetic method including operational convenience, high efficiency and wide-application.

Photosynthesis and Molecular Structure of 2-Amino-3H-phenoxazin-3-one

The single crystal of the title compound (C12H8N2O2, Mr = 212.20) has been obtained by oxidation of 2-aminophenol in methanol solution with irradiation of sunlight. The crystal belongs to monoclinic space group P21/c with cell dimensions of a = 12.925(2), b = 5.077(3), c = 14.768(3)? b = 99.38(1), V = 956.2(5)?, Z = 4, Dc = 1.474 g/cm3, = 0.103 mm-1, R = 0.054, wR = 0.074 for 785 observed reflections (I > 2s(I)). The molecule consists of three coplanar rings. Much different CC distances (1.494(4)?and 1.343(6) ? observed within the quinoidal ring show the pattern of bond fixation expected for the Kekule formula.

Synthesis of Unprotectedα-Tertiary Amines and 1,2-Amino Alcohols from Vinyl Azides by Light Induced Denitrogenative Alkylarylation/Dialkylation

Sterically congestedα-tertiary primary amines are ubiquitous substructures in pharmaceutical and agrochemical agents yet are challenging to access.Herein,straightforward photoredox-catalyzed access to structurally diverseα,α,α-trisubstituted primary amines from denitrogenative alkylarylation or dialkylation of vinyl azides with N-hydroxyphthalimide(NHPI)esters and cyanoarenes or aryl aldehydes has been developed.The use of vinyl azide as a precursor to a primary aminewas enabled by the dual role of the Hantzsch ester to form an electron donor-acceptor complex and serve as a sacrificial reductant.This strategy provides a modular synthesis ofα-tertiary primary amines,including unprotected 1,2-amino alcohols,from simple materials with excellent functional group tolerance.The synthetic applicability of this method was demonstrated by streamlined access to 2,2-disubstituted tetrahydroquinolines.Preliminary investigations support two parallel reductive photocatalytic cycles allowing for the denitrogenative alkylarylation or dialkylation of vinyl azides via decarboxylative radical addition followed by heteroradical cross-coupling betweenα-amino radicals and aryl anion radicals or ketyl anion radicals.

Qualitative and quantitative detection of aldehydes in DNA with 2-amino benzamidoxime derivative

An aldehyde-reactive probe based on 2-amino benzamidoxime(ABAO)framework was introduced,which can selectively label aldehydes in DNA through intramolecular ring closure under mild aqueous solutions.We screened ABAO derivatives that can undergo a cyclization with the formylated nucleobases to generate a fluorescence nucleoside,and of these derivatives 5–methoxy-ABAO(PMA)emerged as the optimal choice.PMA can sensitively and selectively react with 5f U,5f C and AP to form fluorogenic dihydroquinazoline derivatives,which also can quantify DNA damages induced byγ-irradiation.PMA-initiated labeling strategy provides great convenience for qualitative and quantitative detection of aldehydes in DNA.

磷脂酶A_2氨基末端衍生肽的合成及其抗细菌活性的研究

目的 探讨磷脂酶A_(2)(PLA_(2))氨基末端衍生肽的合成及抗菌活性。方法 根据PLA_(2)氨基末端氨基酸残基的顺序合成为多肽PLA_(2)N_(11)、PLA_(2)N_(15)、PLA_(2)N_(20),将其分别与2种细菌(大肠埃希菌、枯草杆菌)在特定条件下培养,并以生理盐水作为对照,分析抗菌活性。结果 与对照比较,多肽不同作用浓度时PLA_(2)N_(11)、PLA_(2)N_(15)、PLA_(2)N_(20)对革兰氏阳性枯草杆菌杀菌活性更强,各多肽间比较,差异有统计学意义(P<0.05);当多肽作用浓度为500μg/ml时,PLA_(2)N_(15)对革兰氏阳性枯草杆菌杀菌活性可达99.8%,高于PLA_(2)N_(11)、PLA_(2)N_(20),及对照(P<0.05)。与对照比较,各多肽不同作用浓度时对大肠埃希菌杀菌活性比较,差异有统计学意义(P<0.05);多肽作用浓度为7.81、125.00、500.00μg/ml时,PLA_(2)N_(15)的杀菌活性均高于PLA_(2)N_(11)和PLA_(2)N_(20),及对照(P<0.05);多肽作用浓度为31.25μg/ml时,PLA_(2)N_(15)的杀菌活性低于PLA_(2)N_(11)的杀菌活性,且高于PLA_(2)N_(20)的杀菌活性(P<0.05)。结论 多肽PLA_(2)N_(11)、PLA_(2)N_(15)、PLA_(2)N_(20)对枯草杆菌、大肠埃希菌有很强的杀菌作用。