578-76-7Relevant articles and documents
Use of 13C as an indirect tag in 15N specifically labeled nucleosides. Syntheses of [8-13C-1,7,NH2-15N3]adenosine, -guanosine, and their deoxy analogues.
Shallop, Anthony J,Gaffney, Barbara L,Jones, Roger A
, p. 8657 - 8661 (2003)
We have previously reported the use of a 13C tag at the C2 of 15N-multilabeled purine nucleosides to distinguish the adjacent-labeled 15N atoms from those in an untagged nucleoside. We now introduce the use of an indirect tag at the C8 of 15N7-labeled purine nucleosides. This tag allows unambiguous differentiation between a pair of 15N7-labeled purines in which only one is 13C8 labeled. Although the very small C8-N7 coupling (200 Hz) because H8 is coupled to both N7 and C8. The 13C8 atom is introduced by means of a ring closure of the exocyclic amino groups of a pyrimidinone using [13C]sodium ethyl xanthate. Here, we present methods for the syntheses of [8-13C-1,7,NH2-15N3]adenosine, -guanosine, and their deoxy analogues.
Use of Nucleoside Phosphorylases for the Preparation of Purine and Pyrimidine 2′-Deoxynucleosides
Drenichev, Mikhail S.,Alexeev, Cyril S.,Kurochkin, Nikolay N.,Mikhailov, Sergey N.
supporting information, p. 305 - 312 (2018/01/15)
Enzymatic transglycosylation – the transfer of the carbohydrate moiety from one heterocyclic base to another – is being actively developed and applied for the synthesis of practically important nucleosides. This reaction is catalyzed by nucleoside phosphorylases (NPs), which are responsible for reversible phosphorolysis of nucleosides to yield the corresponding heterocyclic bases and monosaccharide 1-phosphates. We found that 7-methyl-2′-deoxyguanosine (7-Me-dGuo) is an efficient and novel donor of the 2-deoxyribose moiety in the enzymatic transglycosylation for the synthesis of purine and pyrimidine 2′-deoxyribonucleosides in excellent yields. Unlike 7-methylguanosine, its 2′-deoxy derivative is dramatically less stable. Fortunately, we have found that 7-methyl-2′-deoxyguanosine hydroiodide may be stored for 24 h in Tris-HCl buffer (pH 7.5) at room temperature without significant decomposition. In order to optimize the reagent ratio, a series of analytical transglycosylation reactions were conducted at ambient temperature. According to HPLC analysis of the transglycosylation reactions, the product 5-ethyl-2′-deoxyuridine (5-Et-dUrd) was obtained in high yield (84–93%) by using a small excess (1.5 and 2.0 equiv.) of 7-Me-dGuo over 5-ethyluracil (5-Et-Ura) and 0.5 equiv. of inorganic phosphate. Thymidine is a less effective precursor of α-d-2-deoxyribofuranose 1-phosphate (dRib-1p) compared to 7-Me-dGuo. We synthesized 2′-deoxyuridine, 5-Et-dUrd, 2′-deoxyadenosine and 2′-deoxyinosine on a semi-preparative scale using the optimized reagent ratio (1.5:1:0.5) in high yields. Unlike other transglycosylation reactions, the synthesis of 2-chloro-2′-deoxyadenosine was performed in a heterogeneous medium because of the poor solubility of the initial 2-chloro-6-aminopurine. Nevertheless, this nucleoside was prepared in good yield. The developed enzymatic procedure for the preparation of 2′-deoxynucleosides may compete with the known chemical approaches. (Figure presented.).
Structural and biochemical characterization of the nucleoside hydrolase from C. elegans reveals the role of two active site cysteine residues in catalysis
Singh, Ranjan Kumar,Steyaert, Jan,Versées, Wim
, p. 985 - 996 (2017/05/01)
Nucleoside hydrolases (NHs) catalyze the hydrolysis of the N-glycoside bond in ribonucleosides and are found in all three domains of life. Although in parasitic protozoa a role in purine salvage has been well established, their precise function in bacteria and higher eukaryotes is still largely unknown. NHs have been classified into three homology groups based on the conservation of active site residues. While many structures are available of representatives of group I and II, structural information for group III NHs is lacking. Here, we report the first crystal structure of a purine-specific nucleoside hydrolase belonging to homology group III from the nematode Caenorhabditis elegans (CeNH) to 1.65? resolution. In contrast to dimeric purine-specific NHs from group II, CeNH is a homotetramer. A cysteine residue that characterizes group III NHs (Cys253) structurally aligns with the catalytic histidine and tryptophan residues of group I and group II enzymes, respectively. Moreover, a second cysteine (Cys42) points into the active site of CeNH. Substrate docking shows that both cysteine residues are appropriately positioned to interact with the purine ring. Site-directed mutagenesis and kinetic analysis proposes a catalytic role for both cysteines residues, with Cys253 playing the most prominent role in leaving group activation.
Production, characterization and synthetic application of a purine nucleoside phosphorylase from Aeromonas hydrophila
Ubiali, Daniela,Serra, Carla D.,Serra, Immacolata,Morelli, Carlo F.,Terreni, Marco,Albertini, Alessandra M.,Manitto, Paolo,Speranzab, Giovanna
experimental part, p. 96 - 104 (2012/04/11)
Purine nucleoside phosphorylase (PNP) from Aeromonas hydrophila encoded by the deoD gene has been over-expressed in Escherichia coli, purified, characterized about its substrate specificity and used for the preparative synthesis of some 6-substituted purine-9-ribosides. Substrate specificity towards natural nucleosides showed that this PNP catalyzes the phosphorolysis of both 6-oxo- and 6-aminopurine (deoxy)ribonucleosides. A library of nucleoside analogues was synthesized and then submitted to enzymatic phosphorolysis as well. This assay revealed that 1-, 2-, 6- and 7-modified nucleosides are accepted as substrates, whereas 8-substituted nucleosides are not. A few transglycosylation reactions were carried out using 7-methylguanosine iodide (4) as a d-ribose donor and 6-substituted purines as acceptor. In particular, following this approach, 2- amino-6-chloropurine-9-riboside (2c), 6-methoxypurine- 9-riboside (2d) and 2-amino-6-(methylthio)purine- 9-riboside (2g) were synthesized in very high yield and purity.
HETEROCYCLIC GTP CYCLOHYDROLASE 1 INHIBITORS FOR THE TREATMENT OF PAIN
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Page/Page column 48, (2011/04/19)
The present invention relates to the field of small molecule heterocyclic inhibitors of GTP cyclohydrolase (GCH-I), or a tautomer, prodrug, or pharmaceutically acceptable salt thereof. The invention also features pharmaceutical compositions of the compounds and the medical use of these compounds for the treatment or prevention of pain (e.g., inflammatory pain, nociceptive pain, functional pain, or neuropathic pain).
BODIPY-modified 2′-deoxyguanosine as a novel tool to detect DNA damages
Takamura-Enya, Takeji,Ishii, Ryoko
body text, p. 4206 - 4209 (2011/08/10)
BODIPY-modified 2′-deoxyguanosine was synthesized for use as a detection reagent for genotoxic compounds. BODIPY-FL is a well known fluorescence reagent whose fluorescent light emission diminishes near a guanine base by a photo-induced electron transfer process. We attached BODIPY-Fl to the 5′ position of the deoxyribose moiety of 2′-deoxyguanosine. Although this compound has low fluorescence activity, when depurination by the action of alkylating reagents and dG oxidation by singlet oxygen occurred, the emission of strong fluorescence was observed. BODIPY-dG was found, therefore, to be a very useful tool for selectively detecting DNA damaging activity particularly in natural environmental extracts.
Kinetic properties of Cellulomonas sp. purine nucleoside phosphorylase with typical and non-typical substrates: Implications for the reaction mechanism
Wielgus-Kutrowska, Beata,Bzowska, Agnieszka
, p. 471 - 476 (2008/02/01)
Phosphorolysis catalyzed by Cellulomonas sp. PNP with typical nucleoside substrate, inosine (Ino), and non-typical 7-methylguanosine (m7Guo), with either nucleoside or phosphate (Pi) as the varied substrate, kinetics of the reverse synthetic reaction with guanine (Gua) and ribose-1-phosphate (R1P) as the varied substrates, and product inhibition patterns of synthetic and phosphorolytic reaction pathways were studied by steady-state kinetic methods. It is concluded that, like for mammalian trimeric PNP, complex kinetic characteristics observed for Cellulomonas enzyme results from simultaneous occurrence of three phenomena. These are sequential but random, not ordered binding of substrates, tight binding of me substrate purine bases, leading to the circumstances that for such substrates (products) rapid-equilibrium assumptions do not hold, and a dual role of Pi, a substrate, and also a reaction modifier that helps to release a tightly bound purine base. Copyright Taylor & Francis, Inc.
Spectroscopic and kinetic studies of interactions of calf spleen purine nucleoside phosphorylase with 8-azaguanine, and its 9-(2-phosphonylmethoxyethyl) derivative
Wierzchowski, Jacek,Stepniak, Katarzyna,Bzowska, Agnieszka,Shugar, David
, p. 459 - 464 (2008/02/02)
Spectroscopic and kinetic studies of interactions of calf spleen purine nucleoside phosphorylase with 8-azaguanine, an excellent fluorescent/fluorogenic substrate for the synthetic pathway of the reaction, and its 9-(2-phosphonylmethoxyethyl) derivative, a bisubstrate analogue inhibitor, were carried out. The goal was to clarify the catalytic mechanism of the enzymatic reaction by identification of ionic/tautomeric forms of these ligands in the complex with PNP. Copyright Taylor & Francis, Inc.
2-Pivalamido-3H-pyrimidin-4-one derivatives: Convenient pivalamide hydrolysis using Fe(NO3)3 in MeOH
Bavetsias,Henderson,McDonald
, p. 5643 - 5644 (2007/10/03)
A simple methodology for pivalamide (trimethylacetamide, pivaloylamino) hydrolysis has been discovered using Fe(NO3)3 in MeOH at room temperature. The pivalamido group of 2-pivalamido-3H-pyrimidin-4-ones or fused 2-pivalamido-3H-pyrimidin-4-ones such as 2-pivalamido-3H-quinazolin-4-ones and 2-pivalamido-3H-pteridines have been hydrolysed under these conditions to afford the corresponding amine.
The Cu2+-promoted cleavage of mRNA 5'-cap analogs: A kinetic study with p1(7-methylguanosin-5'-yl) p3-(nucleosid-5'-yl) triphospates and p1- (7-methylguanosin-5'-yl) p4-(guanosin-5'-yl) tetraphosphate
Wieczorek, Zbigniew,Darzynkiewicz, Edward,Kuusela, Satu,Loennberg, Harri
, p. 11 - 21 (2007/10/03)
A kinetic study on the cleavage of a number of mRNA 5'-cap analogs, m7GpppN and m7GppppG, with Cu2+ aquo ion has been performed. Time- dependent product distributions at various pH and metal ion concentrations have been determined by capillary zone electrophoresis, and these data have been used to calculate the rate constants for various parallel reactions of the breakdown of the cap analogs.
