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1.
Oxidation of 2′-hydroxy-8-methylspiro[4H-benz-1,3-oxazin-2-one-6,1′-cyclopentane] or N-mesyl-2-(cyclopent-1-en-1-yl)-6-methylaniline provided the corresponding ketones. The rearrangement of these ketones oximes under treatment with thionyl chloride gave rise to nitriles of 5-(2-amino-3-methylphenyl)-5-oxopentanoic or 5-(2-methanesulfamido-3-methylphenyl)-5-hydroxypentanoic acids. By heating 5-(2-acetylamido-3-methylphenyl)-5-oxopentanoic acid with LiH in THF3-(2,8-dimethylquinol-4-on-3-yl)propanoic acid was obtained. 相似文献
2.
E. A. Dikusar V. I. Potkin D. A. Rudakov T. D. Zvereva S. K. Petkevich M. M. Ogorodnikova A. P. Yuvchenko M. P. Bei 《Russian Journal of General Chemistry》2012,82(3):413-416
A method of preparative synthesis of o(m)-carborane-containing azomethines via the condensation of o(m)-carboranyl-C-methylene-4-formylbenzoates with aliphatic, cycloaliphatic, and aromatic amines was developed. 相似文献
3.
U. S. Makhmudov Sh. B. Rakhimov B. Tashkhodzhaev M. G. Levkovich V. I. Vinogradova 《Chemistry of Natural Compounds》2008,44(2):208-212
The molecular structures of N-(o-and p-hydroxybenzyl)cytisine were investigated by NMR spectroscopy, x-ray structure analysis, and molecular modeling. It was found
that NMR resonances of the OH and aromatic protons in N-(o-hydroxybenzyl)cytisine were doubled because of the presence of two conformers in solution.
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Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 165–168, March–April, 2008. 相似文献
4.
K. Manoj R. G. Gonnade M. M. Bhadbhade M. S. Shashidhar 《Journal of Structural Chemistry》2010,51(4):725-730
The title compound, C29H26O10S, yields two conformational polymorphs concomitantly from dichloromethane-methanol mixture; the major polymorph grows as
plates (Form I, monoclinic, P21/n) and the minor polymorph grows as needles (Form II, triclinic, P-1). The two forms differ mainly in orientation of the tosyl group. In Form I, sulfonyl oxygen of the tosyl group makes intermolecular
C −H…O interactions, whereas the same group in Form II is involved in an intramolecular short dipolar S=O…C=O (sulfonyl-carbonyl)
contact. The molecular organization and the influence of various weak non-covalent interactions that stabilize these conformers
in the crystal lattices are discussed. 相似文献
5.
S. X. Xiao J. J. Zhang X. Li L. J. Ye H. W. Gu N. Ren 《Journal of Thermal Analysis and Calorimetry》2010,102(2):813-817
A ternary binuclear complex of dysprosium chloride hexahydrate with m-nitrobenzoic acid and 1,10-phenanthroline, [Dy(m-NBA)3phen]2·4H2O (m-NBA: m-nitrobenzoate; phen: 1,10-phenanthroline) was synthesized. The dissolution enthalpies of [2phen·H2O(s)], [6m-HNBA(s)], [2DyCl3·6H2O(s)], and [Dy(m-NBA)3phen]2·4H2O(s) in the calorimetric solvent (VDMSO:VMeOH = 3:2) were determined by the solution–reaction isoperibol calorimeter at 298.15 K to be
\Updelta\texts H\textmq \Updelta_{\text{s}} H_{\text{m}}^{\theta } [2phen·H2O(s), 298.15 K] = 21.7367 ± 0.3150 kJ·mol−1,
\Updelta\texts H\textmq \Updelta_{\text{s}} H_{\text{m}}^{\theta } [6m-HNBA(s), 298.15 K] = 15.3635 ± 0.2235 kJ·mol−1,
\Updelta\texts H\textmq \Updelta_{\text{s}} H_{\text{m}}^{\theta } [2DyCl3·6H2O(s), 298.15 K] = −203.5331 ± 0.2200 kJ·mol−1, and
\Updelta\texts H\textmq \Updelta_{\text{s}} H_{\text{m}}^{\theta } [[Dy(m-NBA)3phen]2·4H2O(s), 298.15 K] = 53.5965 ± 0.2367 kJ·mol−1, respectively. The enthalpy change of the reaction was determined to be
\Updelta\textr H\textmq = 3 6 9. 4 9 ±0. 5 6 \textkJ·\textmol - 1 . \Updelta_{\text{r}} H_{\text{m}}^{\theta } = 3 6 9. 4 9 \pm 0. 5 6 \;{\text{kJ}}\cdot {\text{mol}}^{ - 1} . According to the above results and the relevant data in the literature, through Hess’ law, the standard molar enthalpy of
formation of [Dy(m-NBA)3phen]2·4H2O(s) was estimated to be
\Updelta\textf H\textmq \Updelta_{\text{f}} H_{\text{m}}^{\theta } [[Dy(m-NBA)3phen]2·4H2O(s), 298.15 K] = −5525 ± 6 kJ·mol−1. 相似文献
6.
A. V. Piskunov I. N. Meshcheryakova E. V. Baranov G. K. Fukin V. K. Cherkasov G. A. Abakumov 《Russian Chemical Bulletin》2010,59(2):361-370
New tin(iv) mono- and bis-o-iminosemiquinone complexes were obtained by the exchange reaction of radical anion lithium salt of 4,6-di-tert-butyl-N-(2,6-diisopropylphenyl)-o-imino-benzoquinone with tin(iv) organochlorides. The compounds synthesized were characterized by EPR spectroscopy and X-ray diffraction analysis. Substituents
on the tin atom were found to affect stability of paramagnetic metal derivatives formed. 相似文献
7.
Mixed complexes of the type: Zn(Hsal)2(2-MeHim)2, Zn(Han)2(2-MeHim)2, Cd(Hsal)2(2-MeHim)2, Cd(Han)2(2-MeHim)2, where Hsal=OHC6H4COO−, Han=NH2C6H4COO−, 2-MeHim=2-methylimidazol) have been synthesized and characterized by IR spectroscopic and X-ray diffraction studies. Single-crystal
X-ray structure of Cd(Hsal)2(2-MeHim)2 has been obtained. Thermal behaviour of the compounds was investigated by thermal analysis (TG, DTG, DTA). A coupled TG-MS
system was used to analyse the principal volatile products of complexes. Thermal decomposition pathways have been postulated. 相似文献
8.
T. F. Ibragimov M. G. Levkovich V. A. Saprykina Kh. M. Shakhidoyatov 《Chemistry of Natural Compounds》2010,46(5):767-770
N-Chloroacetylcytisine was synthesized by acylation of (–)-cytisine. Stable Z- and E-conformers with respect to rotational isomerism around the N-12–CO bond were found in PMR spectra at room temperature. The
point at which PMR resonances of the Z- and E-conformers coalesced upon heating was measured. The transition barrier between the conformers was estimated. 相似文献
9.
The photochemical reaction of o-iodo- and o-bromophenol in an aqueous sodium sulfite solution proceeds via both nonchain and chain mechanisms. The formation of the intermediate
product, aromatic radical anion, was observed. The quantum yield of the photochemical reaction of o-iodophenol increases, when the electron donor diphenylamine is irradiated. In the photolysis of o-halophenols in organic solvents, free iodine is evolved in addition to aromatic products. The products of the photolysis
of o-iodophenol in ethanol and carbon tetrachloride were identified by gas chromatography-mass spectrometry. These are phenol
in the case of ethanol and a mixture of o-chlorophenol and hydroxychloro-substituted biphenyls in the case of carbon tetrachloride. The quantum yields were determined
for all photochemical reactions studied. 相似文献
10.
A. V. Lezov G. E. Polushina A. A. Lezov P. S. Vlasov N. S. Domnina 《Polymer Science Series A》2011,53(2):93-101
The hydrodynamic and conformational properties of molecules of poly(N,N-diallyl-N,N-dimethylammonium chloride) and N,N-diallyl-N,N-dimethylammonium chloride-maleic acid copolymers of different compositions in solutions with various ionic-strength and pH
values, as well as of the polyelectrolyte complex based on the copolymer with dodecyl sulfate anions in chloroform, are studied.
For poly(N,N-diallyl-N,N-dimethylammonium chloride) molecules in a 1 M NaCl solution, the Kuhn segment length and the hydrodynamic diameter of the
chain are estimated as A = 3.9 nm and d = 0.48 nm, respectively. In acidic solutions with pH 3.5, the copolymers demonstrate behavior typical for polyelectrolytes.
In an alkaline solution with pH 13, when 1 M NaCl is added to the solution of the copolymer containing 29 mol % maleic acid
units, there is an antipolyelectrolyte effect that manifests itself as an increase in the intrinsic viscosity of the copolymer
and in the hydrodynamic radius of its molecules. It is found that an increase in the fraction of maleic acid units in the
copolymer from 12 to 42 mol % brings about a reduction in the equilibrium rigidity of its macromolecules from 4.1 to 2.2 nm.
The equilibrium rigidity of polyelectrolyte-complex molecules is higher than that of initial copolymer molecules owing to
steric interactions arising between the aliphatic chains of dodecyl sulfate anions. In an electric field, the molecules of
the complex are oriented owing to the induced dipole moment resulting from the displacement of dodecyl sulfate anions along
the chain contour. 相似文献
11.
D. F. Grishin L. B. Vaganova A. V. Piskunov O. S. Lizyakina M. G. Chegerev 《Doklady Chemistry》2017,475(1):149-154
The effect of a number of quinoid compounds on methyl methacrylate polymerization initiated by azo-bis(isobutyronitrile) has been studied. It has been revealed that N-aryl-o-iminobenzoquinones, in contrast to o-benzoquinones, can provide radical polymerization of methyl methacrylate in controllable mode. The efficiency of the compounds as chain growth regulators has been found to depend on their composition and reaction conditions. It has been established that 4,6-di-tert-butyl-N-(2,6-diethylphenyl)-o-iminobenzoquinone and 4,6-di-tert-butyl-N-(2,6-diisopropylphenyl)-o-iminobenzoquinone under radical initiation conditions provide the synthesis of poly(methyl methacrylate) with wide-range molecular weight, retaining polydispersity indices about ~1.4–1.8 up to deep conversions. 相似文献
12.
A. I. Vorob’eva M. S. Babaev L. V. Spirikhin N. M. Shishlov S. V. Kolesov 《Russian Journal of Applied Chemistry》2016,89(1):160-164
A copolymer of N,N-diallyl-N,N-dimethylammonium chloride with maleic acid of constant composition was prepared under the conditions of radical initiation. The possibility of the functionalization of the copolymer with drugs containing amino groups by polymer-analogous transformations was examined. Conditions were found for preparing conjugates of the copolymer with isoniazid. The structures and the quantitative compositions of the conjugates were determined by 13С NMR spectroscopy, and the possibility of preparing conjugates with controlled drug content was demonstrated. 相似文献
13.
o- and p-Hydroxybenzohydrazides reacted with various unsaturated aromatic aldehydes to give the corresponding N′-(hydroxybenzoyl)hydrazones. Inhibitory activity of the obtained hydrazones against cathepsin E was evaluated. 相似文献
14.
L. A. Baltina A. I. Fairushina L. A. Baltina 《Russian Journal of General Chemistry》2015,85(12):2735-2738
Synthesis of amino acid conjugates of glycyrrhizic acid with the use of N-hydroxyphthalimide, N,N'-dicyclohexylcarbodiimide, and tert-butyl esters of L-amino acids (valine, isoleucine, phenylalanine, and methionine) was performed followed by deprotection with trifluoroacetic acid. The target amino acid conjugates were isolated by column chromatography on silica gel in 40–45% yield. The structure of the prepared compounds was confirmed by IR and 13C NMR spectroscopy. 相似文献
15.
A. A. Druzhinin N. E. Kaurov S. A. Nemkov V. A. Ishutin 《Journal of Analytical Chemistry》2010,65(12):1242-1244
A chemiluminescence method was developed for determining o-chlorobenzylidenemalonic acid dinitrile (o-CBMA DN) in extracts. The method is based on chemiluminescence developed in a strong alkaline solution upon the interaction between
3-aminophthalic hydrazide (luminol) with the superoxide radical formed in the reaction of atmospheric oxygen activated by
hemin with the products of the alkaline hydrolysis of o-chlorobenzylidenemalonic acid dinitrile and with the products of their condensation with p-nitrobenzaldehyde. The luminescence intensity of luminol was proportional to the concentration of o-CBMA DN in the range 1 × 10−6−1 × 10−1 mg/mL. The determination limit for o-CBMA DN was (1 ± 0.3) × 10−6 mg/mL (p = 95%, n = 5, RSD = 29%) at 293 K. 相似文献
16.
M. A. Kinzhalov G. L. Starova M. Haukka V. P. Boyarskii 《Russian Journal of General Chemistry》2016,86(10):2350-2355
Reactions of palladium(II) bis-isocyanide complexes cis-[PdCl2(CNR)2] (R = 2,6-Me2C6H3, 2-Me-6-ClC6H3) with an equimolar amount of chelating N,O-binucleophiles, 2-aminophenol and (2-aminophenyl)-methanol, in acetonitrile at room temperature in 24 h selectively afforded the corresponding open-chain monocarbene complexes. The complexation involved one isocyanide ligand and amino group of the aromatic amine. Neither bis(carbene) complexes (in the reactions with 4 equiv of the nucleophile under harsh conditions) nor C,O-chelate structures were detected. The isolated complexes were characterized by elemental analyses, IR, NMR, and mass spectra, and X-ray diffraction data. 相似文献
17.
A number of (Z)-N,N-dialkyl- and (Z)-N-acyl-N-alkyl-O-methylnicotinamide oximes was synthesized. Their configuration was confirmed by the NOESY experiment. Evaluation of fungicidal
activity of compounds obtained was performed. 相似文献
18.
4-Nitro-o-xylene was selectively oxidized to 2-methyl-4-nitrobenzoic acid using dilute nitric acid as the oxidizing agent under atmospheric pressure. The oxidation of 4-nitro-o-xylene was effectively promoted by an addition of radical initiators. Under reflux, 2-methyl-4-nitrobenzoic acid was afforded in high yield using nitric acid combined with N-hydroxyphthalimide, cobalt dichloride (CoCl2 · 6H2O), manganese acetate (Mn(OAc)2 · 4H2O) and phase transfer catalyst. 相似文献
19.
20.
G. S. Kuanysheva K. U. Dzhamansarieva G. Zh. Sdikova 《Russian Journal of Inorganic Chemistry》2007,52(9):1359-1362
The mean atomic Gibbs energies of formation of (Δ f ? at 0 ) of s-, p-, and d-element diphosphates have been calculated using ion increments of the Gibbs energy (Δ f G 0). The diphosphate hydrolysis kinetics is considered, and a correlation between the Δ f ? at 0 values and the hydrolysis rate constants is presented. 相似文献