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1.
A. V. Kolotaev L. I. Belen’kii A. S. Kononikhin M. M. Krayushkin 《Russian Chemical Bulletin》2006,55(5):892-897
Symmetrical and unsymmetrical α-diketones of the indole series were synthesized by the Friedel-Crafts reaction of 3-indolylglyoxyl
chlorides with heterocycles. A nonconventional reaction of N-unsubstituted diketones with hydrazine producing 3H-pyrazolo[3,4-c]quinoline derivatives was found.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 862–866, May, 2006. 相似文献
2.
Yu. I. Kostyukevich A. S. Kononikhin I. A. Popov A. E. Bugrova N. L. Starodubtseva E. N. Nikolaev 《High Energy Chemistry》2016,50(6):427-432
At present, the secondary structure of oligonucleotide ions in a gas phase is almost not understood. One of the main points is the retention of a hairpin secondary structure during ionization. In this work, we used a deuterium–hydrogen exchange reaction in a gas phase at atmospheric pressure for studying the conformational dynamics of oligonucleotide ions formed as a result of electrospray ionization. The exchange reactions of two oligonucleotides, which consisted of the identical sets of nucleotides but differed in their sequence, have been studied. One of these oligonucleotides formed a hairpin secondary structure, but the other did not. It has been found that both of the oligonucleotides demonstrate similar reaction dynamics of deuterium/hydrogen exchange in the gas phase; thereby indicating that the secondary structure has been completely destroyed during ionization. 相似文献
3.
Yury Kostyukevich Alexey Kononikhin Alexander Zherebker Igor Popov Irina Perminova Eugene Nikolaev 《Analytical and bioanalytical chemistry》2014,406(26):6655-6664
We report a simple approach for enumeration of non-labile oxygen atoms in individual molecules of dissolved organic matter (DOM), using acid-catalyzed 16O/18O exchange and ultrahigh-resolution Fourier-transform ion-cyclotron-resonance mass spectrometry (FTICR-MS). We found that by dissolving DOM in H2 18O at 95 °C for 20 days it is possible to replace all oxygen atoms of DOM molecules (excluding oxygen from ether groups) with 18O. The number of exchanges in each molecule can be determined using high-resolution FTICR. Using the proposed method we identified the number of non-labile oxygen atoms in 231 molecules composing DOM. Also, using a previously developed hydrogen–deuterium (H/D)-exchange approach we identified the number of labile hydrogen atoms in 450 individual molecular formulas. In addition, we observed that several backbone hydrogen atoms can be exchanged for deuterium under acidic conditions. The method can be used for structural and chemical characterization of individual DOM molecules, comparing different DOM samples, and investigation of biological pathways of DOM in the environment. 相似文献
4.
Observation of the multiple halogenation of peptides in the electrospray ionization source 下载免费PDF全文
Yury Kostyukevich Ekaterina Zhdanova Alexey Kononikhin Igor Popov Eugene Kukaev Eugene Nikolaev 《Journal of mass spectrometry : JMS》2015,50(7):899-905
The chlorination of peptides and proteins is an important posttranslational modification, which is a physiological signature of an enzyme myeloperoxidase and can serve as a potential biomarker of some diseases (Parkinson's disease, Alzheimer's disease, etc.). The quantification of the chlorinated peptides has been very challenging in part due to their low levels and artifacts associated with sample preparation. One of the most convenient and promising methods to detect and investigate the chlorinated peptides in the biological samples is the electrospray ionization (ESI) mass spectrometry coupled to the fragmentation techniques (collision‐induced dissociation and electron capture dissociation/electron transfer dissociation). We have shown that if the chlorine anions are present in the solution, then the peptide can undergo the chlorination during the ESI ionization. The effect was found to depend on the values of electric potentials of metal parts of the ESI interface. It was found that the grounding of ESI syringe results in the formation of an additional electric loop leading to the electrolytic production of Cl2 and as a consequence the hypochlorous acid inside the ESI needle. Hypochlorous acid reacts with amino groups of peptides and proteins producing chloramine or causing the protein cleavage. In the paper, it is shown on the example of the solution of the several peptides in the presence of HCl that by manipulating the ESI syringe potential, it is possible to create complexes with up to five Cl atoms for sample peptides when the ESI is operated in the positive mode. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Vitaliy Chagovets Zhihao Wang Alexey Kononikhin Natalia Starodubtseva Anna Borisova Dinara Salimova Igor Popov Andrey Kozachenko Konstantin Chingin Huanwen Chen Vladimir Frankevich Leila Adamyan Gennady Sukhikh 《Journal of the American Society for Mass Spectrometry》2018,29(2):323-330
Recent research revealed that tissue spray mass spectrometry enables rapid molecular profiling of biological tissues, which is of great importance for the search of disease biomarkers as well as for online surgery control. However, the payback for the high speed of analysis in tissue spray analysis is the generally lower chemical sensitivity compared with the traditional approach based on the offline chemical extraction and electrospray ionization mass spectrometry detection. In this study, high resolution mass spectrometry analysis of endometrium tissues of different localizations obtained using direct tissue spray mass spectrometry in positive ion mode is compared with the results of electrospray ionization analysis of lipid extracts. Identified features in both cases belong to three lipid classes: phosphatidylcholines, phosphoethanolamines, and sphingomyelins. Lipids coverage is validated by hydrophilic interaction liquid chromatography with mass spectrometry of lipid extracts. Multivariate analysis of data from both methods reveals satisfactory differentiation of eutopic and ectopic endometrium tissues. Overall, our results indicate that the chemical information provided by tissue spray ionization is sufficient to allow differentiation of endometrial tissues by localization with similar reliability but higher speed than in the traditional approach relying on offline extraction. 相似文献
7.
The effect of space flight on the protein composition of the exhaled breath condensate of cosmonauts
Fedorchenko K. Yu. Ryabokon’ A. M. Kononikhin A. S. Mitrofanov S. I. Mikhant’eva E. A. Spasskii A. I. Sukhodolov I. R. Popov I. A. Polyakov A. V. Larina I. M. Nikolaev E. N. Varfolomeev S. D. 《Russian Chemical Bulletin》2016,65(11):2745-2750
Russian Chemical Bulletin - As a part of development of medicine for extreme situations, we determined, for the first time, the protein composition of the exhaled breath condensate (EBC) of... 相似文献
8.
The investigation of the bitumen from ancient Greek amphora using FT ICR MS,H/D exchange and novel spectrum reduction approach. 下载免费PDF全文
Yury Kostyukevich Sergey Solovyov Alexey Kononikhin Igor Popov Eugene Nikolaev 《Journal of mass spectrometry : JMS》2016,51(6):430-436
Recently Russian archeologists have discovered on Taman peninsula an ancient (V B.C.) Greek amphora full of dense bitumen. This is the oldest amphora in the world that contains bitumen. We report the investigation of this bitumen using ultrahigh resolution Fourier transform mass spectrometry. Also we used recently developed in‐ESI source Hydrogen/Deuterium exchange approach for the structural characterization of the individual molecules and estimation of the biodegradation of the bitumen. The increase of number of the labile hydrogens compared to the non‐degraded oil can serve as an additional evidence of the degradation of bitumen via oxidation. For the facilitation of the spectrum processing we have developed the special iterative spectrum reduction approach. It was observed that molecules that have only oxygen heteroatoms possess two –OH groups what is unusual for the petroleum. Based on this we suggested that the bitumen degraded during its being in amphora for 2500 years. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
9.
O. V. Demina A. S. Kononikhin A. V. Laptev A. A. Khodonov E. N. Nikolaev S. D. Varfolomeev 《Russian Chemical Bulletin》2012,61(2):422-441
The model peptide synthesis from mixtures of amino acids was carried out under the thermal cycling and isothermal modes. The compositions of the obtained mixtures of products and the primary amino acid sequence of the synthesized peptides were determined by Fourier transform ion cyclotron resonance mass spectrometry and tandem mass spectrometry in combination with high-performance liquid chromatography with the application of de novo sequencing of the synthesized products. The processes of abiogenous synthesis of peptides were shown to occur under relatively mild temperature conditions and give a substantially less number of peptides as compared with the possible statistical set. The evolution of the system takes place in the process of the synthesis in solid phase with the disappearance of a series of the most unstable peptides. The selection process with the formation of complementary peptides takes place in peptide synthesis under the thermal cyclic mode. 相似文献