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5. Automation of Copper-Mediated 18 F-Fluorination of Aryl Pinacol Boronates Using 4-Dimethylaminopyridinium Triflate.

Author

Nadporojskii, Mikhail A., Orlovskaya, Viktoriya V., Fedorova, Olga S., Sysoev, Dmitry S., and Krasikova, Raisa N.

Subjects
COPPER, BIOCHEMICAL substrates, RADIOISOTOPES, SULFONATES, AUTOMATION, RADIOACTIVE tracers
Abstract

Currently, the copper-mediated radiofluorination of aryl pinacol boronates (arylBPin) using the commercially available, air-stable Cu(OTf)2Py4 catalyst is one of the most efficient synthesis approaches, greatly facilitating access to a range of radiotracers, including drug-like molecules with nonactivated aryl scaffolds. Further adjustment of this methodology, in particular, the [18F]fluoride recovery step for the routine preparation of radiotracers, has been the focus of recent research. In our recent study, an organic solution of 4-dimethylaminopyridinium trifluoromethanesulfonate (DMAPOTf) was found to be an efficient PTC for eluting radionuclides retained on the weak anion exchange cartridge, Oasis WAX 1cc, employing the inverse sorption–elution protocol. Notably, the following Cu-mediated radiofluorination of arylBPin precursors in the presence of the Cu(OTf)2(Py)4 catalyst can be performed with high efficiency in the same solvent, bypassing not only the conventional azeotropic drying procedure but any solvent replacement. In the current study, we aimed to translate this methodology, originally developed for remote-controlled operation with manual interventions, into the automated synthesis module on the TRACERlab automation platform. The adjustment of the reagent amounts and solvents allowed for high efficiency in the radiofluorination of a series of model arylBPin substrates on the TRACERlab FXFE Pro synthesis module, which was adapted for nucleophilic radiofluorinations. The practical applicability of the developed radiofluorination approach with DMAPOTf elution was demonstrated in the automated synthesis of 6-L-[18F]FDOPA. The radiotracer was obtained with an activity yield (AY; isolated, not decay-corrected) of 5.2 ± 0.5% (n = 3), with a synthesis time of ca. 70 min on the TRACERlab FX N Pro automation platform. The obtained AY was comparable with one reported by others (6 ± 1%) using the same boronate precursor, while a slightly higher AY of 6-L-[18F]FDOPA (14.5 ± 0.5%) was achieved in our previous work using commercially available Bu4NOTf as the PTC. [ABSTRACT FROM AUTHOR]

Published
2024
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16. Analyses of pre-steady-state kinetics and isotope effects of the γ-elimination reaction catalyzed by Citrobacter freundii methionine γ-lyase

Author

Kuznetsova, Aleksandra A., primary, Faleev, Nicolai G., additional, Morozova, Elena A., additional, Anufrieva, Natalya V., additional, Gogoleva, Olga I., additional, Tsvetikova, Marina A., additional, Fedorova, Olga S., additional, Demidkina, Tatyana V., additional, and Kuznetsov, Nikita A., additional

Published
2022
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20. Opisthorchis Felineus Infection is a Risk Factor for Cholangiocarcinoma in Western Siberia: A Hospital-based Case-control Study

Author

Fedorova, Olga S, primary, Kovshirina, Anna E, additional, Kovshirina, Yulia V, additional, Hattendorf, Jan, additional, Onishchenko, Sergey V, additional, Katanakhova, Ludmila L, additional, Taslicki, Stanislav S, additional, Chizhikov, Andrey V, additional, Tataurov, Ilya А, additional, Vtorushin, Sergey V, additional, Sripa, Banchob, additional, Ogorodova, Ludmila M, additional, and Odermatt, Peter, additional

Published
2022
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23. One-Pot Radiosynthesis of [ 18 F]Anle138b—5-(3-Bromophenyl)-3-(6-[ 18 F]fluorobenzo[ d ][1,3]dioxol-5-yl)-1 H -pyrazole—A Potential PET Radiotracer Targeting α-Synuclein Aggregates.

Author

Orlovskaya, Viktoriya V., Fedorova, Olga S., Viktorov, Nikolai B., Vaulina, Daria D., and Krasikova, Raisa N.

Subjects
*RADIOACTIVE tracers, *ALPHA-synuclein, *RING formation (Chemistry), *POSITRON emission tomography, *PARKINSON'S disease, *CONDENSATION reactions, *RADIOLABELING
Abstract

Availability of PET imaging radiotracers targeting α-synuclein aggregates is important for early diagnosis of Parkinson's disease and related α-synucleinopathies, as well as for the development of new therapeutics. Derived from a pyrazole backbone, 11C-labelled derivatives of anle138b (3-(1,3-benzodioxol-5-yl)-5-(3-bromophenyl)-1H-pyrazole)—an inhibitor of α-synuclein and prion protein oligomerization—are currently in active development as the candidates for PET imaging α-syn aggregates. This work outlines the synthesis of a radiotracer based on the original structure of anle138b, labelled with fluorine-18 isotope, eminently suitable for PET imaging due to half-life and decay energy characteristics (97% β+ decay, 109.7 min half-life, and 635 keV positron energy). A three-step radiosynthesis was developed starting from 6-[18F]fluoropiperonal (6-[18F]FP) that was prepared using (piperonyl)(phenyl)iodonium bromide as a labelling precursor. The obtained 6-[18F]FP was used directly in the condensation reaction with tosylhydrazide followed by 1,3-cycloaddition of the intermediate with 3′-bromophenylacetylene eliminating any midway without any intermediate purifications. This one-pot approach allowed the complete synthesis of [18F]anle138b within 105 min with RCY of 15 ± 3% (n = 3) and Am in the range of 32–78 GBq/µmol. The [18F]fluoride processing and synthesis were performed in a custom-built semi-automated module, but the method can be implemented in all the modern automated platforms. While there is definitely space for further optimization, the procedure developed is well suited for preclinical studies of this novel radiotracer in animal models and/or cell cultures. [ABSTRACT FROM AUTHOR]

Published
2023
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24. Opisthorchis Felineus Infection is a Risk Factor for Cholangiocarcinoma in Western Siberia: A Hospital-based Case-control Study.

Author

Fedorova, Olga S, Kovshirina, Anna E, Kovshirina, Yulia V, Hattendorf, Jan, Onishchenko, Sergey V, Katanakhova, Ludmila L, Taslicki, Stanislav S, Chizhikov, Andrey V, Tataurov, Ilya A, Vtorushin, Sergey V, Sripa, Banchob, Ogorodova, Ludmila M, and Odermatt, Peter

Subjects
*HOSPITALS, *PHYSICAL diagnosis, *LIVER function tests, *CONFIDENCE intervals, *IMMUNOGLOBULINS, *CHOLANGIOCARCINOMA, *LIVER, *MICROSCOPY, *SERUM, *FOOD consumption, *CASE-control method, *INTERVIEWING, *ACQUISITION of data, *EARLY detection of cancer, *RISK assessment, *FECES, *FISHING, *HOSPITAL care, *RESEARCH funding, *DESCRIPTIVE statistics, *QUESTIONNAIRES, *ENZYME-linked immunosorbent assay, *MEDICAL records, *BLOOD sedimentation, *FISHES, *SOCIAL classes, *BILE ducts, *ODDS ratio, *DATA analysis software, *ABDOMINAL pain, *BLOOD cell count, *SMOKING, *STATISTICAL models, *OPISTHORCHIASIS, *DIETARY sodium, *EARLY medical intervention, *DISEASE risk factors, ULTRASONIC imaging of the abdomen
Abstract

Background Cholangiocarcinoma (CCA), a fatal bile duct cancer, has a high incidence in Western Siberia, Russian Federation. In addition, Opisthorchis felineus , a bile duct–dwelling trematode liver fluke is highly endemic. Closely related species have been shown to be cancerogenic agents in Asia. We therefore examined the association between O felineus infection and CCA in Western Siberia. Methods We conducted a hospital-based, individually matched case-control study between January 2017 and August 2020 in Tomsk Oblast and Khanty-Mansiysk Autonomous Okrug, Yugra, Russian Federation. Histologically confirmed CCA patients (cases) were compared with matched age, sex, and place of residence hospital controls. The examination of study participants included the diagnosis of current and past O felineus infection, abdominal ultrasonographical assessment, physical examination, and interview on exposures to potential risk factors. Results We identified 40 patients with CCA and 160 controls. Exposures to O felineus infection was strongly associated with CCA (odds ratio [OR], 3.9; 95% confidence interval [CI], 1.4–10.8; P =.008). Also, cases reported more often that they were currently or in the past were infected by O felineus compared with controls (OR, 4.03; 95% CI, 1.7–9.5; P =.001). Furthermore, cases reported river fish consumption and fishing habits significantly more often than controls (OR, 5.5; 95% CI, 1.5–19.8; P =.009 and OR, 3.3; 95% CI, 1.4–7.7; P =.005). Conclusions The study results revealed a strong significantly increased risk for CCA development in O felineus –infected individuals. Elaboration of the guidelines on screening programs for early CCA diagnosis, prevention, and treatment is socially important in endemic regions. [ABSTRACT FROM AUTHOR]

Published
2023
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30. Pre-Steady-State Kinetics of the SARS-CoV-2 Main Protease as a Powerful Tool for Antiviral Drug Discovery

Author

Zakharova, Maria Yu., primary, Kuznetsova, Alexandra A., additional, Uvarova, Victoria I., additional, Fomina, Anastasiia D., additional, Kozlovskaya, Liubov I., additional, Kaliberda, Elena N., additional, Kurbatskaia, Inna N., additional, Smirnov, Ivan V., additional, Bulygin, Anatoly A., additional, Knorre, Vera D., additional, Fedorova, Olga S., additional, Varnek, Alexandre, additional, Osolodkin, Dmitry I., additional, Ishmukhametov, Aydar A., additional, Egorov, Alexey M., additional, Gabibov, Alexander G., additional, and Kuznetsov, Nikita A., additional

Published
2021
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31. Automated Optimized Synthesis of [ 18 F]FLT Using Non-Basic Phase-Transfer Catalyst with Reduced Precursor Amount.

Author

Fedorova, Olga S., Orlovskaya, Viktoriya V., and Krasikova, Raisa N.

Subjects
*PHASE-transfer catalysts, *POSITRON emission tomography, *RADIOCHEMICAL purification, *BREAST, *SOLID phase extraction, *HYDROLYSIS, *BREAST tumors
Abstract

3′-deoxy-3′-[18F]fluorothymidine ([18F]FLT) is a positron emission tomography (PET) tracer useful for tumor proliferation assessment for a number of cancers, particularly in the cases of brain, lung, and breast tumors. At present [18F], FLT is commonly prepared by means of the nucleophilic radiofluorination of 3-N-Boc-5′-O-DMT-3′-O-nosyl thymidine precursor in the presence of a phase-transfer catalyst, followed by an acidic hydrolysis. To achieve high radiochemical yield, relatively large amounts of precursor (20–40 mg) are commonly used, leading to difficulties during purification steps, especially if a solid-phase extraction (SPE) approach is attempted. The present study describes an efficient method for [18F]FLT synthesis, employing tetrabutyl ammonium tosylate as a non-basic phase-transfer catalyst, with a greatly reduced amount of precursor employed. With a reduction of the precursor amount contributing to lower amounts of synthesis by-products in the reaction mixture, an SPE purification procedure using only two commercially available cartridges—OASIS HLB 6cc and Sep-Pak Alumina N Plus Light—has been developed for use on the GE TRACERlab FX N Pro synthesis module. [18F]FLT was obtained in radiochemical yield of 16 ± 2% (decay-corrected) and radiochemical purity >99% with synthesis time not exceeding 55 min. The product was formulated in 16 mL of normal saline with 5% ethanol (v/v). The amounts of chemical impurities and residual solvents were within the limits established by European Pharmacopoeia. The procedure described compares favorably with previously reported methods due to simplified automation, cheaper and more accessible consumables, and a significant reduction in the consumption of an expensive precursor. [ABSTRACT FROM AUTHOR]

Published
2022
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36. Production of 6-l-[F-18]Fluoro-m-tyrosine in an Automated Synthesis Module for C-11-Labeling

Author

Orlovskaya, Viktoriya V., Craig, Austin S., Fedorova, Olga S., Kuznetsova, Olga F., Neumaier, Bernd, Krasikova, Raisa N., Zlatopolskiy, Boris D., Orlovskaya, Viktoriya V., Craig, Austin S., Fedorova, Olga S., Kuznetsova, Olga F., Neumaier, Bernd, Krasikova, Raisa N., and Zlatopolskiy, Boris D.

Abstract

6-l-[F-18]Fluoro-m-tyrosine (6-l-[F-18]FMT) represents a valuable alternative to 6-l-[F-18]FDOPA which is conventionally used for the diagnosis and staging of Parkinson's disease. However, clinical applications of 6-l-[F-18]FMT have been limited by the paucity of practical production methods for its automated production. Herein we describe the practical preparation of 6-l-[F-18]FMT using alcohol-enhanced Cu-mediated radiofluorination of Bpin-substituted chiral Ni(II) complex in the presence of non-basic Bu4ONTf using a volatile iPrOH/MeCN mixture as reaction solvent. A simple and fast radiolabeling procedure afforded the tracer in 20.0 +/- 3.0% activity yield within 70 min. The developed method was directly implemented onto a modified TracerLab FX C Pro platform originally designed for C-11-labeling. This method enables an uncomplicated switch between C-11- and F-18-labeling. The simplicity of the developed procedure enables its easy adaptation to other commercially available remote-controlled synthesis units and paves the way for a widespread application of 6-l-[F-18]FMT in the clinic.

Published
2021

41. Amino Acid Formulas in Patients with Gastrointestinal Diseases

Author

Baranov, Alexander A., primary, Namazova-Baranova, Leyla S., additional, Alexeeva, Anna A., additional, Ambarchian, Eduard T., additional, Aslamazyan, Lianna K., additional, Astafieva, Natalia G., additional, Balykova, Larisa A., additional, Belyaeva, Irina A., additional, Bulgakova, Vilya A., additional, Vakhlova, Irina V., additional, Vashakmadze, Nato D., additional, Vishneva, Elena A., additional, Getiya, Ekaterina G., additional, Il’ina, Natalia I., additional, Kaytukova, Elena V., additional, Kamaltynova, Elena M., additional, Karkashadze, Georgiy A., additional, Kovtun, Olga P., additional, Komarova, Elena V., additional, Kulichenko, Tatiana V., additional, Kurbacheva, Oksana M., additional, Levina, Yuliya G., additional, Makarova, Svetlana G., additional, Murashkin, Nikolay N., additional, Nesterova, Yuliya V., additional, Novik, Gennady A., additional, Piskunova, Svetlana G., additional, Popova, Larisa Yu., additional, Privalova, Tatyana E., additional, Selimzyanova, Lilia R., additional, Sergienko, Natalia S., additional, Serebryakova, Elena N., additional, Stasiy, Ekaterina D., additional, Tkachenko, Mikhail A., additional, Turti, Tatiana V., additional, Ustinova, Natalia V., additional, Fedorova, Olga S., additional, Fomina, Daria S., additional, Fugol’, Denis S., additional, Chemakina, Daria S., additional, Shepeleva, Irina M., additional, and Efendieva, Kamilla E., additional

Published
2021
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43. C-11- and F-18-labelled tryptophans as PET-tracers for imaging of altered tryptophan metabolism in age-associated disorders

Author

Zlatopolskiy, Boris D., Endepols, Heike, Krasikova, Raisa N., Fedorova, Olga S., Ermert, Johannes, Neumaier, Bernd, Zlatopolskiy, Boris D., Endepols, Heike, Krasikova, Raisa N., Fedorova, Olga S., Ermert, Johannes, and Neumaier, Bernd

Abstract

The ageing of the world's population is the result of increased life expectancy observed in almost all countries throughout the world. Consequently, a rising tide of ageing-associated disorders, like cancer and neurodegenerative diseases, represents one of the main global challenges of the 21st century. The ability of mankind to overcome these challenges is directly dependent on the capability to develop novel methods for therapy and diagnosis of age-associated diseases. One hallmark of age-related pathologies is an altered tryptophan metabolism. Numerous pathological processes including neurodegenerative and neurological diseases like epilepsy, Parkinson's and Alzheimer's diseases, cancer and diabetes exhibit marked changes in tryptophan metabolism. Visualization of key processes of tryptophan metabolic pathways, especially using positron emission tomography (PET) and related hybrid methods like PET/CT and PET/MRI, can be exploited to early detect the aforementioned disorders with considerable accuracy, allowing appropriate and timely treatment of patients. Here we review the published C-11- and F-18-labelled tryptophans with respect to the production and also preclinical and clinical evaluation as PET-tracers for visualization of different branches of tryptophan metabolism.

Published
2020

44. Amino acid formulas in patients with food allergy

Author

Baranov, Alexander A., primary, Namazova-Baranova, Leyla S., additional, Alexeeva, Anna A., additional, Ambarchian, Eduard T., additional, Aslamazyan, Lianna K., additional, Astafieva, Natalia G., additional, Balykova, Larisa A., additional, Belyaeva, Irina A., additional, Bulgakova, Vilya A., additional, Vakhlova, Irina V., additional, Vashakmadze, Nato D., additional, Vishneva, Elena A., additional, Getiya, Ekaterina G., additional, Il'ina, Natalia I., additional, Kaytukova, Elena V., additional, Kamaltynova, Elena M., additional, Karkashadze, Georgiy A., additional, Kovtun, Olga P., additional, Komarova, Elena V., additional, Kulichenko, Tatiana V., additional, Kurbacheva, Oksana M., additional, Levina, Yuliya G., additional, Makarova, Svetlana G., additional, Murashkin, Nikolay N., additional, Nesterova, Yuliya V., additional, Novik, Gennady A., additional, Piskunova, Svetlana G., additional, Popova, Larisa Yu., additional, Privalova, Tatyana E., additional, Selimzyanova, Lilia R., additional, Sergienko, Natalia S., additional, Serebryakova, Elena N., additional, Stasiy, Ekaterina D., additional, Tkachenko, Mikhail A., additional, Turti, Tatiana V., additional, Ustinova, Natalia V., additional, Fedorova, Olga S., additional, Fomina, Daria S., additional, Fugol, Denis S., additional, Chemakina, Daria S., additional, Shepeleva, Irina M., additional, and Efendieva, Kamilla E., additional

Published
2021
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46. Thermodynamic, kinetic, and structural basis for recognition and repair of 8-oxoguanine in DNA by Fpg protein from Escherichia coli

Author

Ishchenko, Alexander A., Vasilenko, Nataliya L., Sinitsina, Olga I., Yamkovoy, Vitalyi I., Fedorova, Olga S., Douglas, Kenneth T., and Nevinsky, Gregory A.

Subjects
DNA repair -- Models, Oligodeoxynucleotides -- Testing, DNA-ligand interactions -- Analysis, Protein binding -- Analysis, Biological sciences, Chemistry
Abstract

Thermodynamic models for the interaction between specific and nonspecific DNA sequences and Fpg protein reveal that Fpg interacts nonspecifically with all the base-pair units within its DNA-binding cleft with a 7 orders of magnitude of affinity for DNA. However, with 8-oxoguanine unit of the substrate Fpg exhibits 6-8 orders of magnitude affinity for specific oligodeoxynucleotides.

Published
2002

47. Stopped-flow kinetic studies of the interaction between Escherichia coli Fpg protein and DNA substrates

Author

Fedorova, Olga S., Nevinsky, Georgy A., Koval, Vladimir V., Ishchenko, Alender A., Vasilenko, Nataly L., and Douglas, Kenneth T.

Subjects
Biochemistry -- Research, Escherichia coli -- Physiological aspects, Proteins -- Physiological aspects, DNA damage -- Physiological aspects, Tryptophan -- Physiological aspects, Fluorescence -- Physiological aspects, Biological sciences, Chemistry
Abstract

Research has been conducted on Escherichia coli's formamidopyrimidine-DNA-glycosylase which repairs oxidative DNA damage. The kinetic mechanism for the 8-oxoguanine excision from DNA substrate with Fpg protein has been investigated via the tryptophan fluorescence application and the results are reported.

Published
2002

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