English version Ukrainian version
Last issue Archive Editorial board Instructions to authors Contact us




This site supported by
 
2006 Vol IV #1



Microwave assisted synthesis of 1,4-dihydropyridines

Sandeep A. Kotharkar, Devanand B. Shinde

Department of Chemical Technology
Dr Babasaheb Ambedkar Marathwada University, Aurangabad (M.S.) – 431004 India

Abstract: A novel method, which is eco-friendly, cost effective, solvent free, was developed for the synthesis of 1,4-dihydropyridines from ethyl acetoacetate, aldehyde and ammonium acetate under domestic microwave oven.

Keywords: Hantzsch synthesis, microwave

Full-text in PDF Contact authors



S
ynthesis of 1,2-trans glycosyl fluorides of 2-amino-2-deoxysugars containing urethane N-protecting groups


S.S. Pertel, E.S. Kakayan, V.Ya. Chirva

National Taurida V. Vernadsky University
4 Vernadsky ave., Simferopol, Crimea, 95007, Ukraine

Abstract: An interaction of 2-acylamino-2-deoxysugar glycosyl halides with tetrabutylammonium fluoride was studied. For the most part the relatively stable 2-alkyl glyco-[2,1-d]-2-oxazolines was the main products of the reaction. 2-alkyl glycooxazolines did not react with TBAF probably because of high basicity and low nucleophilicity of fluoride ions. It was found that the target 1,2-trans glycosyl fluorides of 2-acylamino-2-deoxysugars could be obtained by the reaction of 2-alcoxycarbonylamino-2-deoxyglycosyl halides with TBAF. It seems that the 1,2-trans-glycosyl fluorides are formed in this case due to high reactivity of intermediate 2-alkoxy glyco-[2,1-d]-2-oxazolines.

Keywords: 1,2-trans glycosyl fluorides of 2-acylamino-2-deoxy sugars, intramolecular nucleophilic substitution, glycooxazolines, anchimeric participation.

Full-text in PDF Contact authors



New approach to the synthesis of 4'-dialkylamino-3-hydroxyflavones


S.A. Demchenko, V.G. Pivovarenko

Taras Shevchenko National University
64 Volodymyrska str., Kyiv, 01033, Ukraine


Abstract: A series of 3-hydroxy-4'-piperazinoflavones (3HF) were synthesized with the purpose of development of new fluorescence probes. A new approach was proposed to the synthesis of this group of compounds, consisting in nucleophilic substitution of fluorine atom in aromatic ring by the dialkylamino group of secondary amines. Optimal conditions for the preparation of 3HF were found.

Keywords: flavonols, 3-hydroxyflavones, fluorescent probes, nucleophilic substitution.

Full-text in PDF Contact authors


This article is sponsored by Otava, Ltd.

Novel styrylcyanines and their dimers as fluorescent dyes for nucleic acids detection: synthesis and spectral-luminescent studies

A.O. Balanda, K.D. Volkova, V.B. Kovalska, M.Yu. Losytskyy, S.S. Lukashov, S.M. Yarmoluk

Institute of Molecular Biology and Genetics, NAS of Ukraine
150 Zabolotny Str., Kyiv, 03143, Ukraine


Abstract: With the aim to design DNA-sensitive fluorescent probes, a series of novel (p-dimethylaminostyryl) benzothiazolium dyes with tetraalkylammonium residues were synthesized. Spectral-luminescent properties of obtained dyes in free state and in the presence of nucleic acids and BSA (bovine serum albumin) were studied. It was shown that dimeric styrylcyanines with linker containing two tetraalkylammonium residues demonstrated 3 orders of magnitude fluorescence increase in the presence of DNA. The interaction mechanism between synthesized styrylcyanines and dsDNA was studied and possible binding mechanism was suggested. The possibility to use styrylcyanines as probes for fluorescent nucleic acids in vivo visualization was revealed.

Keywords: styrylcyanine dyes, nucleic acids detection.

Full-text in PDF Contact authors


This article is sponsored by Otava, Ltd.

N
ew highly sensitive fluorescent dye Barva NA for DNA visualization after the denaturing gradient gel electrophoresis


O.O. Solovyov, L.A. Livshits, V.B. Kovalska, M.Yu. Losytskyy, Yu.L. Slominski
1, S.M. Yarmoluk

Institute of Molecular Biology and Genetics, NAS of Ukraine
150 Zabolotny str., Kyiv, 03143, Ukraine
1Institute of Organic Chemistry, NAS of Ukraine
5 Murmans’ka str., Kyiv, 02094, Ukraine

Abstract: The comparison of the efficiency of cyanine dye Barva NA (Otava, Ukraine), the analogue of SYBR Green, and ethidium bromide for visualization of PCR products of exon 20 CFTR gene after mutant alleles separation using denaturing gradient gel electrophoresis (DGGE) was performed. The higher sensitivity of Barva NA was shown.

Keywords: DGGE, gene, cystic fibrosis, mutations, Barva NA, ethidium bromide, DNA visualization.

Full-text in PDF Contact authors



Intramolecular hydrogen bonds in 2'-deoxyuridine conformers: results of non-empirical quantum chemical analysis of electron density topology


R.O. Zhurakivsky, D.M. Hovorun
1

Taras Shevchenko National University
2 Glushkova ave, Kyiv, 03127, Ukraine
1Institute of Molecular Biology and Genetics, NAS of Ukraine
150 Zabolotny Str., Kyiv, 03143, Ukraine

Abstract: In 94 all the conceivable conformers of minor nucleoside 2'-deoxyuridine 14 types of intramolecular hygrogen bonds (among the total number of 175 ones) were first established by the AIM (Atom-in-Molecules) theory analysis of electron density topology obtained at the B3LYP/6-31G(d,p) level of quantum chemical calculations. These types are C1'H...O2, C2'H2...O5', C2'H2...O2, C3'H...O2, C5'H1...O2, C5'H2...O2, C6H...O4', C6H...O5', C3'H...HC6, O5'H...HC6, O3'H...O5', O5'H...O3', O5'H...O4', O5'H...O2. Conformational, geometric and electron-topological properties of H-bonds are presented.

Keywords: 2'-deoxyuridine, nucleosides, intramolecular hydrogen bonds, electron density topology analysis, quantum chemical conformational analysis.

Full-text in PDF Contact authors



Oligonucleotide conjugates with intercalating agents: synthesis and biological activity


I.Ya. Dubey

Institute of Molecular Biology and Genetics, NAS of Ukraine
150 Zabolotny Str., Kyiv, 03143, Ukraine

Abstract: Modification of oligonucleotides with intercalating agents improves their binding affinity to target nucleic acids while maintaining high sequence specificity that allows an efficient regulation of gene expression by blocking the replication, transcription or translation process. Intercalators are planar polyaromatic compounds that interact with DNA double and triple helix. They bind by insertion between adjacent base pairs and stabilize complementary complexes of nucleic acids. These conjugates have been extensively studied in vitro and in vivo as a tool to investigate the biological processes and as potential anticancer and antiviral therapeutic agents. In this review, the various approaches to the synthesis of modified oligonucleotides are summarized, and their conjugates with major intercalating agents are described. Factors influencing the hybridization efficiency and biologic activity of conjugates are discussed.

Keywords: Oligonucleotide conjugates, intercalating agents, DNA, duplexes, triple helix.

Full-text in PDF Contact authors

 

Home