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1.
[reaction: see text] A new aminobenzannulation methodology has been developed and applied successfully to the synthesis of 1-amino-acridines. The key and last step goes through an enamine intermediate that was detected in some cases. When pyrrolidine and powdered 4 A molecular sieves were used, the enamine synthesis and the aminobenzannulation step took place subsequently, whereas for other secondary amines, neutral Al(2)O(3) or PtCl(2) catalysis was necessary. 相似文献
2.
The inhibition performance of five azomethine derivatives such as: 1-(4-Methyloxy phenylimino)-1-(phenylhydrazono)-propan-2-one (SB1), 1-(4-Methylphenylimino)-1-(phenylhydrazono) propan-2-one (SB2), 1-(phenylimino)-1(phenylhydrazono)-propan-2-one (SB3), 1-(4-Bromo phenylimino)-1(phenylhydrazono)-propan-2-one (SB4) and 1-(4-Chlorophenylimino)-1(phenylhydrazono) -propan-2-on (SB5) as corrosion inhibitors for mild steel in sulfuric acid 0.5 ?M were investigated using different methods. All experimental results demonstrate that these compounds are eficients inhibitors. The inhibition efficiencies () increase with inhibitors concentration. At 7.5 10?5 ?M, the was 97.27%, 96.31%, 94.23%, 93.19 and 91.64% for SB1, SB2, SB3, SB4 and SB5, respectively. The potentiodynamic polarization results indicated that all the studied inhibitors act as mixed type. The adsorption process on mild steel surface obeyed Langmuir isotherm. The associated activation parameters and thermodynamic have been calculated and discussed. The adsorbed film formed on the metal surface was characterized by SEM and EDX. 相似文献
3.
Chaabouni SE Mechichi T Limam F Marzouki N 《Applied biochemistry and biotechnology》2005,125(2):99-112
Two endoglucanases (EGs), EG A and EG B, were purified to homogeneity from Penicillium occitanis mutant Pol 6 culture medium. The molecular weights of EG A and EG B were 31,000 and 28,000 kDa, respectively. The pI was about 3 for EG A and 7.5 for EG B. Optimal activity was obtained at pH 3.5 for both endoglucanases. Optimal temperature for enzyme activity was 60 degrees C for EG A and 50 degrees C for EG B. EG A was thermostable at 60 degrees C and remained active after 1 h at 70 degrees C. EGs hydrolyzed carboxymethylcellulose, phosphoric acid swollen cellulose, and beta-glucan efficiently, whereas microcrystalline cellulose (Avicel) and laminarin were poorly hydrolyzed. Only EG B showed xylanase activity. Furthermore, these EGs were insensitive to the action of glucose and cellobiose but were inhibited by the divalent cations Hg2+, Co2+, and Mn2+. 相似文献
4.
L. Poul M. Fakhfakh M. Taibi N. Jouini P. Herson F. Fiévet 《Journal of chemical crystallography》2005,35(4):285-291
[Cd5(OH)(H2O)3][CH3CO2]9 crystallizes in the triclinic system, with the space group P
, a = 10.897(3) Å, b = 11.035(5) Å, c = 16.061(12) Å, = 96.83(7), = 95.31(8), = 118.22(6) and z = 2. Its structure has been determined using 9497 unique single crystal data. The final refinements let the agreement factors R1 and wR2(F2) converge to reach the respective values of 0.0548 and 0.0986. R1 = 0.0338 for the 7264 unique data with I > 2(I). [Cd5(OH)(H2O)3][CH3CO2]9 is a cadmium hydroxide acetate compound with a bi-dimensional structure in which hydrogen bonds insure cohesion between layers stacked along the [1
10] direction. The inorganic network is built up of layers constituted of CdO6 octahedra and CdO7 pentagonal bi-pyramids sharing edge or corner. 相似文献
5.
Slaheddine Chaabouni Slaheddine Kamoun Abdelaziz Daoud Tahar Jouini 《Journal of chemical crystallography》1997,27(7):401-404
The pentakis ethylenediammonium bis undecachlorodiantimonate(III) tetrahydrate salt is monoclinic with the following unit
cell dimensions:a=16.271(5) Å,b=13.004(4) Å,c=13.932(4) Å, β=111.72(2)°, space groupP21/c withZ=2. The structure was solved by Patterson methods and refined to a finalR value of 0.023 for 4435 reflections withF
0>4σ(F
0). The structure shows a layer arrangement perpendicular to thea axis: planes of the [Sb2Cl11]5− bioctahedra alternate with planes of [NH3(CH2)2NH3]2+ dications. The [Sb2Cl11]5− bioctahedra are connected through O−H...Cl hydrogen bonds, such that infinite chains of composition [Sb2Cl11(H2O]n
5n− are formed in the structure, parallel to the twofold axis. These chains are themselves interconnected by means of N−H...Cl
and O−H...Cl bonds originating from the [NH3(CH2)2NH3]2+ entities and the water molecules, respectively, and form a threedimensional network. 相似文献
6.
Slaheddine Chaabouni Slaheddine Kamoun Abdelaziz Daoud Tahar Jouini 《Journal of chemical crystallography》1991,27(7):401-404
The pentakis ethylenediammonium bis undecachlorodiantimonate(III) tetrahydrate salt is monoclinic with the following unit
cell dimensions:a=16.271(5) Å,b=13.004(4) Å,c=13.932(4) Å, β=111.72(2)°, space groupP21/c withZ=2. The structure was solved by Patterson methods and refined to a finalR value of 0.023 for 4435 reflections withF
0>4σ(F
0). The structure shows a layer arrangement perpendicular to thea axis: planes of the [Sb2Cl11]5− bioctahedra alternate with planes of [NH3(CH2)2NH3]2+ dications. The [Sb2Cl11]5− bioctahedra are connected through O−H...Cl hydrogen bonds, such that infinite chains of composition [Sb2Cl11(H2O]n
5n− are formed in the structure, parallel to the twofold axis. These chains are themselves interconnected by means of N−H...Cl
and O−H...Cl bonds originating from the [NH3(CH2)2NH3]2+ entities and the water molecules, respectively, and form a threedimensional network. 相似文献
7.
Amen Allah Hajem Basma Trojette Ahmed Driss Tahar Jouini 《Journal of chemical crystallography》1999,29(2):217-221
The synthesis and crystal structure of a new microporous zincophosphate are described. [H2N2C6H16]0.5[Zn2(PO4)(HPO4)(H2O)]·H2O crystallizes in the triclinic space group P1¯ with a = 8.822(4), b = 9.236(4), c = 8.451(3) Å, = 67.19(3), = 91.32(3), = 111.10(3)°, V = 586.7(4) Å3 and Z = 2. This new material consists of infinite two-dimensional anionic layers alternated with planes containing organic diprotonated templates, N, N, N, N-tetramethylethylenediamine [H2N2C6H16]2+ molecules. The framework structure is built up of ZnO4, ZnO3OH2, PO4, and PO3OH tetrahedra, linked through oxygen vertices. The presence of terminal OH2 and OH groups, leads to an open structure containing four- and eight-rings. The organic molecules are interconnected to the framework through hydrogen bonds. 相似文献
8.
Zakaria Elaoud Slaheddine Kamoun Joel Jaud Tahar Mhiri 《Journal of chemical crystallography》1998,28(4):313-315
The salt N-benzylmethylammonium dihydrogenmonophosphate monohydrate is monoclinic with the following unit cell dimensions: a = 6.356(1)Å, b = 8.385(7)Å, c = 11.472(5)Å, = 104.32(1)°, space group P21 with Z = 2. The structure consists of infinite parallel two-dimensional [110] planes built of mutually connected ions and water molecules by strong O–H···O and N–H···O hydrogen bonding. There are no contacts other than normal van der Waals interactions between the layers. 相似文献
9.
Ben Salah M Vilminot S André G Richard-Plouet M Bourée-Vigneron F Mhiri T Kurmoo M 《Chemistry (Weinheim an der Bergstrasse, Germany)》2004,10(8):2048-2057
[Mn(3)(OH)(2)(SO(4))(2)(H(2)O)(2)] and its deuterated analogue were synthesized by a hydrothermal technique and characterized by differential thermal analysis, thermogravimetric analysis, and IR spectroscopy. Its nuclear structure, determined by single-crystal X-ray analysis and Rietveld analysis of neutron powder-diffraction data, consists of a 3D network of chains of edge-sharing Mn(1)O(6), running along the c axis, connected by the apices of Mn(2)O(6) and SO(4) units. It is isostructural to the nickel analogue. Determination of the magnetic structure and measurements of magnetization and heat capacity indicate the coexistence of both magnetic long-range ordering (LRO) and short-range ordering (SRO) below a Néel temperature of 26 K, while the SRO is retained at higher temperatures. The moments of the two independent Mn atoms lie in the bc plane, and that of Mn(1) rotates continuously by 54 degrees towards the c axis on decreasing the temperature from 25 to 1.4 K. While the SRO may be associated with frustration of the moments within a Mn(3) trimer, the LRO is achieved by antiparallel alignment of the four symmetry-related trimers within the magnetic unit cell. A spin-flop field, measured by dc and ac magnetization on a SQUID, is observed at 15 kOe. 相似文献
10.
Ben Salah M Vilminot S Richard-Plouet M André G Mhiri T Kurmoo M 《Chemical communications (Cambridge, England)》2004,(22):2548-2549
The synthetic mineral Co(II)5(OH)6(SO4)2(H2O)4 (1), obtained by hydrothermal reaction of CoSO4.7H2O and NaOH at 165 degrees C and consisting of brucite-like Co4(OH)6O2 layers pillared by OSO3-Co(H2O)4-O3SO, is a ferromagnet (T(Curie)= 12 K, Hc= 580 Oe). 相似文献