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1.
A new asymmetric phenol-based “end-off” dinucleating ligand HL was prepared using a modified methodology through a four-step
synthesis. The ligand comprises two different coordination moieties, namely, a rigid 1,4-dimethyl-1,4,7-triazacyclononane
unit and a more flexible N-(2-pyridyl)methyl-N-2-(2-pyridylethyl)amine unit. Its dinuclear Ni(II) complex containing two phosphate esters in a μ−η2 binding mode was synthesized and characterized by X-ray crystallography, in which each nickel atom is six-coordinate and
adopts a slightly distorted octahedral coordination geometry. 相似文献
2.
Reactions of 2-(4,5-dihydro-3-furyl)-1,3-diphenyl-1,3-diaza-2λ3-phospholidine (1) with nitrile imines are multistep processes involving cleavage of one P-N bond of the diazaphospholidine ring to form substituted
5-(2-chloroethyl)-4-(N,N′-diphenylethylenediamino)-1,4-dihydro-1,2,4λ5-diazaphosphorines 4 as final products. Analogs of phospholidine 1, namely, 4,5-dihydro-3-furylphosphonous dipiperidide and dimorpholide, react with C,N-diphenylnitrile imine with retention of both P-N bonds to give 5-(2-hydroxyethyl)-1,2,4-diazaphosphorinium chlorides.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1590–1593, July, 2005. 相似文献
3.
Omar M. Ali 《Monatshefte für Chemie / Chemical Monthly》2007,138(9):917-922
Summary. 2-(Arylamino)pyrimidin-4-ones were synthesized, silylated, and condensed with l,2,3,5-tetra-O-acetyl-β- d-ribofuranoside to afford the corresponding N
2-aryl protected isocytidines. Deprotection of the acetylated isocytidines using saturated NH3 in MeOH solution gave 1-(β-d-ribofuranosyl)-2-(arylamino)-4-pyrimidinones. Methyl 2-deoxy-3,5-di-O-toluyl-α/β-d-ribofuranoside was prepared and condensed with the previously silylated bases to afford the anomeric mixture of protected
nucleosides. The pure β-anomers were synthesized with better yield by treating the sodium salts of N
2-arylisocytosine derivatives with 2-deoxy-3,5-di-O-toluyl-α-d-ribofuranosyl chloride. Deprotection of the latter anomers afforded the corresponding free hydroxyl derivatives. The synthesized
free nucleosides are under antiviral and oligonucleotide investigations. 相似文献
4.
Nitro-, nitroso-, and azo-1,2,5-oxadiazoles with 4-R1-5-R2-1,2,3-triazol-1-yl substituents were synthesized by oxidation of amino-(1,2,3-triazol-1-yl)-1,2,5-oxadiazoles (aminotriazolylfurazans).
Azido-1,2,5-oxadiazole was prepared by diazotization of amino(triazolyl)furazan followed by treatment of the diazonium salt
with sodium azide. Depending on the nature of the substituents and the reagent, triazolylfurazans can undergo destruction
to give amino-R-furazans (R = NO2, N3, aminofurazanylazo), the amino group being formed from the triazole ring.
__________
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1859–1865, August, 2005. 相似文献
5.
Summary. The regioselective reaction of N1-benzyl-N2-(4-nitrophenyl)ethanediamide with dialkyl acetylenedicarboxylates or alkyl propiolates in the presence of triphenylphosphine
leads to dialkyl 4-benzylamino-1-(4-nitrophenyl)-5-oxo-2,5-dihydro-1H-pyrrole-2,3-dicarboxylates or alkyl 4-benzylamino-1-(4-nitrophenyl)-2-oxo-5-pyrrolidinecarboxylates in good yields. 相似文献
6.
V. V. Shchepin D. V. Fotin M. I. Vakhrin S. N. Shurov 《Russian Journal of General Chemistry》2004,74(9):1406-1409
The Reformatskii reagents formed from alkyl esters of -bromoacetic, -bromopropanoic, and -bromoisobutyric acids and zinc react with N-arylamides of 2-oxochromene-3-carboxylic acid, yielding 3-R1-1-R2-1-R3-4a,10b-dihydro-1H-chromeno[3,4-c]pyridine-2,4,5-triones.Translated from Zhurnal Obshchei Khimii, Vol. 74, No. 9, 2004, pp. 1516–1519.Original Russian Text Copyright © 2004 by Shchepin, Fotin, Vakhrin, Shurov.This revised version was published online in April 2005 with a corrected cover date. 相似文献
7.
Revital Sasson Dan Vaknin Avihai Bross Efraim Lavie 《Journal of Radioanalytical and Nuclear Chemistry》2010,283(3):753-756
A practical and reliable HPLC method was used for the determination of 2-[4-N-(2-hydroxyethyl)-1-piperazinyl]-N′-ethanesulfonic acid (HEPES) content in the 68Ga-labeled [1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid]-1-Nal3-octreotide (DOTANOC). Linearity of this method
was observed in a concentration range of 0.01–10 mg mL−1 and the quantitative limit (signal to noise = 11) was determined as 10 μg mL−1. The HEPES concentration in the final products of 68Ga-DOTANOC was typically lower than the detection limit. Pure water and HEPES buffer as reaction medium were investigated
using various activities of gallium-68. It was demonstrated that the presence of HEPES buffer consistently furnished very
high radiochemical purity of 68Ga-DOTANOC, which remained stable for several hours post-labeling. Evidence is provided that in addition to its role as a
buffer, HEPES also functions as a radioprotectant agent. 相似文献
8.
Autoradiolysis of the 2-deoxy-2-[<Superscript>18</Superscript>F]fluoro-D-glucose radiopharmaceutical
E. Búriová F. Macášek F. Melichar M. Kropáček L. Procházka 《Journal of Radioanalytical and Nuclear Chemistry》2005,264(3):595-602
Summary To control virtually the toxic compounds and to improve quality control of the solution of 2-deoxy-2-[18F]fluoro-d-glucose (2-[18F]FDG), the products of its autoradiolysis were analyzed by high-performance liquid chromatography with electrospray mass spectrometric and radiometric detectors (HPLC/MS/RAD), thin layer chromatography on TLC silica plate and HPTLC on amino modified silica plate. Except Kryptofix™ 2.2.2, glucose and fluoride anion, no by-products and impurities were observed by LC/MS analysis of fresh 2-[18F]FDG samples. The analysis performed in the time interval of 6 to 48 hours after the end of 2-[18F]FDG synthesis indicated that the activity of the autoradiolysis products separated by HPLC did not exceed 1.3%. As the main autoradiolysis products of 3.3 . 10-5 to 4.4 . 10-5M 2-[18F]FDG solution of original specific activity 0.5-1.5 GBq . cm-3 were established: arabinose - 2.8 μM (G= 0.07/100 eV), gluconic and glucuronic acids 1.8-0.5 μM (G =0.01-0.05/100 eV), arabinose and araburonic acids occurred under 0.5 μM concentration at residual glucose contents about 0.14 mM. Radiation chemical yields of active products were calculated from molar activity of 2-[18F]FDG and the percentage of their activity: 0.5% radiochemical yield of 2-[18F]fluoroglucuronic acid corresponds to the G = 0.004/100 eV and 0.3% yield of 2-[18F]fluorogluconic acid issues G = 0.003/100 eV. 相似文献
9.
N-Bromo and N-chlorosuccinimides add to 1-phenyltricyclo[4.1.0.02,7]heptane in CH2Cl2 with cleavage of the C(1)-C(7) bond to give isomeric 1 : 1 Markownikoff-type endo, anti-adducts of the norpinane structure in a ∼3 :7 ratio corresponding to N and O alkylation of succinimide.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No.2, pp. 457–460, February, 2005 相似文献
10.
Kavita Poonia Sunita Maanju Pratibha Chaudhary R. V. Singh 《Transition Metal Chemistry》2007,32(2):204-208
Synthesis and characterization of titanium(IV) and zirconium(IV) complexes of the types Cp2M(Cl)(HPO), Cp2M(HPO)2, Cp2M(O∩N∩O) and Cp2M(O∩N∩S) (where M represents titanium or zirconium and HPO, O∩N∩O and O∩N∩S represent the donor sets of the ligands) have been reported. These new derivatives have been prepared by the reactions of
titanocene dichloride or zirconocene dichloride with 2-hydroxy-N-phenyl benzamide(HPOH), 1-[(2-hydroxyphenyl)-1-N-phenylamino]hydrazine-carboxamide
(HO∩N∩OH) and 2-hydroxy-N-phenyl benzamide benzothiazoline (HO∩N∩SH) in different molar ratios. The ligands and their complexes have been characterized by the elemental analyses, conductance
measurement, molecular weight determinations and spectral studies. On the basis of electronic, I.r., 1H.-n.m.r. and 13C.-n.m.r. spectral studies, trigonal bipyramidal and octahedral geometries have been proposed for the resulting complexes.
All the ligands and their complexes have been screened for their biological activity on several pathogenic fungi and bacteria
and were found positive in this respect. 相似文献
11.
Rollie J. Myers 《Journal of solution chemistry》2007,36(3):395-403
We have measured the second acid dissociation constant, K
2a
, at several ionic strengths for hydrogen telluride (H2Te) using the Charge Transfer to Solvent (CTTS) uv spectra of its anions HTe− and Te2−. Since it is produced in our solutions, we have also determined the spectra of Te2
2− both in the uv and in the visible regions. At 25 ∘C, K
2a
= (1.28 ± 0.02) × 10−12 by extrapolation to zero ionic strength. Its value at an ionic strength equal to 0.5 mol.dm-3 was estimated to be (8.7 ± 0.2) × 10−12. The solution thermodynamics of these species are also discussed and comparisons are made to related acids. 相似文献
12.
Isothermal titration calorimetry has been used to determine the stoichiometry, formation constants and thermodynamic parameters
(ΔG
o, ΔH, ΔS) for the formation of the citrate complexes with the Mn2+, Co2+, Ni2+ and Zn2+ ions. The measurements were run in Cacodylate, Pipes and Mes buffer solutions with a pH of 6, at 298.15 K. A constant ionic
strength of 100 mM was maintained with NaClO4. The influence of a metal ion on its interaction energy with the citrate ions and the stability of the resulting complexes
have been discussed. 相似文献
13.
A. I. Kuramshin E. V. Asafyeva R. A. Cherkasov 《Russian Journal of Organic Chemistry》2005,41(5):779-783
New tungsten complexes were prepared of a composition η3-[(1,3,5-triorganyl)-1,3,5-triazacyclohexane]-tricarbonyltungsten(0) where a tridentate coordination of the triazinane fragment to the metal center was found. The reaction of tricarbonyltriazinane tungsten complexes with 1,3-diphenyl-2-propen-1-one (chalcone) under thermochemical activation resulted in replacement of two carbon monoxide molecules in the coordination sphere of tungsten by a chalcone molecule linked to the transition metal atom through a system of π-bonds C=C and C=O. The phosphorylation of η4-(1,3-diphenyl-2-propen-1-one)-η3-[(1,3,5-triphenyl)-1,3,5-triazacyclohexane]-monocarbonyltungsten(0) with diethyl phosphite occurred at the carbonyl group of the coordinated heterodiene; the phosphonate thus formed underwent intracomplex phosphonate-phosphate rearrangement affording an organometallic phosphate.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 5, 2005, pp. 793–797.Original Russian Text Copyright © 2005 by Kuramshin, Asafyeva, Cherkasov. 相似文献
14.
Yu. K. Grishin I. P. Gloriozov S. M. Gerdov V. A. Roznyatovsky L. L. Frolova A. V. Kuchin Yu. A. Ustynyuk 《Russian Chemical Bulletin》2008,57(8):1689-1696
The selectivity of deuterium distribution between the nonequivalent positions in 3-carene (1), 4-α-acetyl-2-carene (2), and 4-(1-hydroxyethyl)-2-carene (3) has been measured by 2H-{1H} NMR spectroscopy at the natural abundance of deuterium. These “H/D-isotope portraits” were shown to be typical of terpenes
and terpenoids produced in plants via the biosynthetic DXP pathway. The mechanism of acylation of 1 was studied by the density functional theory method (PBE functional, TZ2p basis set). The six-membered ring in compound 1 is planar. However, the endo attack of electrophiles on this ring is more favorable both kinetically and thermodynamically. It was shown both experimentally
and theoretically that the elimination of a hydrogen atom in the second reaction step proceeds stereoselectively at the C(2)
atom from the anti position with respect to the three-membered ring and occurs with pronounced nucleophilic assistance from the carbonyl group.
For Part 2, see Ref. 1.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1657–1664, August, 2008. 相似文献
15.
Comparative quantum chemical calculations of structural parameters, chemical shifts of 11B NMR spectra, and atomic charges in 10-vertex boron hydride anions [1-CB9H10]− and [1-B10H9N2]− were performed using the restricted Hartree-Fock method with the 6-31++G(D,P) basis set.
Dedicated to Academician G. A. Abakumov on the occasion of his 70th birthday.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1853–1855, September, 2007. 相似文献
16.
I. E. Tolpygin Yu. V. Revinskii A. V. Tsukanov A. D. Dubonosov V. A. Bren’ V. I. Minkin 《Russian Journal of Organic Chemistry》2011,47(9):1305-1309
Condensation of N
2-(anthracen-9-ylmethyl)naphthalene-2,3-diamine with aromatic and heterocyclic aldehydes gave a series of the corresponding
Schiff bases and N-(anthracen-9-ylmethyl)-substituted naphtho-[2,3-d]imidazoles. Study on the luminescence spectra and complexing ability of the condensation products revealed their sensor properties
toward some heavy metal cations. 相似文献
17.
H. N. Altshuler L. P. Abramova N. V. Malyshenko G. Yu. Shkurenko E. V. Ostapova 《Russian Chemical Bulletin》2005,54(8):1978-1981
The ion-exchange equilibrium in network polymers obtained from cis-2,8,14,20-tetraphenyl-4,6,10,12,16,18,22,24-octahydroxycalix[4]arene by template synthesis on cations Na+, K+, and Ba2+ as matrices was studied. The selectivity coefficients of ion exchanges Ba2+-H+, Na+-H+, K+-H+, Na+-K+, and Na+-NH4
+ were determined. The template synthesis enhanced the affinity of the polymers to matrix-forming cations by 6–8 kJ mol−1.
__________
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1919–1922, August, 2005. 相似文献
18.
L. O. Nindakova N. N. Chipanina V. K. Turchaninov M. V. Ustinov B. A. Shainyan 《Russian Chemical Bulletin》2005,54(10):2343-2347
The reaction of di-μ-chlorobis(1,5-cyclooctadiene)dirhodium with (4S, 5S)-2,2-dimethyl-4,5-bis(methylaminomethyl)-1,3-dioxolane (1) gave the complex [Rh(cod)(1)]Cl (cod is 1,5-cyclooctadiene). The composition of the complexes CoCl2 · L2 and [Rh(cod)(L2)]X (L2 = 1, (4S,5S)-2,2-dimethyl-4,5-bis(aminomethyl)-1,3-dioxolane, and (4S, 5S)-2,2-dimethyl-4,5-bis(dimethylaminomethyl)-1,3-dioxolane; X = Cl, TfO) was studied using IR and 1H NMR spectroscopy. In the RhI cyclooctadienediamine complexes, the diene molecule forms a stronger bond with the metal atom than that in the cyclooctadienediphosphine
analogs.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2270–2274, October, 2005. 相似文献
19.
K. P. Butin A. A. Moiseeva E. K. Beloglazkina Yu. B. Chudinov A. A. Chizhevskii A. V. Mironov B. N. Tarasevich A. V. Lalov N. V. Zyk 《Russian Chemical Bulletin》2005,54(1):173-188
N,N’-Polymethylenebis(thiosalicylidene)iminate and macrocyclic dithiadiazadibenzocycloalkadiene complexes of nickel(II) were synthesized and their electrochemical and spectroscopic properties were studied. Dithiadiazadibenzocycloalkadiene complexes containing two DMSO molecules coordinated to Ni2+ and two outer-sphere ClO4
− anions were synthesized by the reaction of the corresponding macrocyclic ligands with Ni(ClO4)2·6H2O. The structure of 3,6-dithia-10,14-diazadibenzo[a,g]cyclopentadeca-9,14-dienylnickel(II)[bis(dimethyl sulfoxide) bis-perchlorate] was established by X-ray diffraction. The UV-Vis spectroscopic data are consistent with octahedral structures of diiminobis(sulfide) complexes, a square-planar structure of the thiosalen complex, and distorted tetrahedral structures of other diiminodithiolate complexes. The reaction of S-tert-butylthiosalicylaldehyde with hydrazine hydrate afforded di(ortho-tert-butylthiobenzal)azine. The reaction of the latter with anhydrous NiCl2 produced a colored complex with the simplest molecular formula Ni(C16H12N2S2) in 15% yield. Semiempirical PM3(tm) calculations and the results of UV-Vis, ESR, and 1H NMR spectroscopy demonstrate that this complex has most probably a dimeric structure, in which two Ni centers adopt a nearly square-planar configuration. The complexes are clearly divided into two types according to their electrochemical behavior in DMF solutions. The type 1 is characterized by reversibility of the first reduction steps. The type 2 is characterized by irreversible two-electron reduction as the first step accompanied by deposition of Ni metal on the electrode surface. Rapid electrochemically initiated alkylation occurs in the presence of various alkylating agents (BunI, BunBr, (DmgH)2CoCH3) in a solution of complex 1 in DMF.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 169–183, January, 2005. 相似文献
20.
A. I. Uraev I. S. Vasil’chenko G. S. Borodkin I. G. Borodkina V. G. Vlasenko A. S. Burlov L. N. Divaeva K. A. Lyssenko M. Yu. Antipin A. D. Garnovskii 《Russian Chemical Bulletin》2005,54(3):633-640
New metal chelates of ZnII and CdII (ML2) based on (4Z)-3-methyl-1- phenyl-5-thioxo-1,5-dihydro-4-H-pyrazol-4-one quinolin-8-ylhydrazone (HL1) and (4Z)-5- methyl-2-phenyl-4-[(quinolin-8-ylimino)methyl]-2,4-dihydro-3H-pyrazole-3-thione (HL2) were synthesized. The structures of the metal chelates were studied by EXAFS and NMR (1H, 13C, and 111Cd) spectroscopy. The structure of the Cd(L1)2 complex was established by X-ray diffraction analysis. The complexes have pseudooctahedral structures with the N4S2 ligand environment.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 623–629, March, 2005. 相似文献