scholarly journals Design and synthesis of purine nucleoside analogues for the formation of stable anti-parallel-type triplex DNA with duplex DNA bearing the 5mCG base pair

RSC Advances ◽  
2021 ◽  
Vol 11 (35) ◽  
pp. 21390-21396
Author(s):  
Ryotaro Notomi ◽  
Lei Wang ◽  
Shigeki Sasaki ◽  
Yosuke Taniguchi
Keyword(s):  
Base Pair ◽  
Purine Nucleoside ◽  
Nucleoside Analogues ◽  
Triplex Dna ◽  
Duplex Dna ◽  
Design And Synthesis ◽  
Direct Recognition ◽  
First Time ◽  
Parallel Type

We herein demonstrated for the first time the direct recognition of duplex DNA bearing the 5-methyl-2′-deoxycytosine and 2′-deoxyguanosine base pair by triplex DNA formation.

Development of novel C-nucleoside analogues for the formation of antiparallel-type triplex DNA with duplex DNA that includes TA and dUA base pairs

2020 ◽  
Vol 18 (15) ◽  
pp. 2845-2851 ◽  
Author(s):  
Yosuke Taniguchi ◽  
Yuya Magata ◽  
Takayuki Osuki ◽  
Ryotaro Notomi ◽  
Lei Wang ◽  
...  
Keyword(s):  
Nucleoside Analogues ◽  
Triplex Dna ◽  
Duplex Dna ◽  
Base Pairs

We report the formation of stable triplex DNA for TA duplex sites by using triplex-forming oligonucleotides (TFOs) with novel C-nucleoside analogues.

Synthesis of C-nucleoside analogues based on the pyrimidine skeleton for the formation of anti-parallel-type triplex DNA with a CG mismatch site

2020 ◽  
Vol 28 (23) ◽  
pp. 115782
Author(s):  
Ryotaro Notomi ◽  
Lei Wang ◽  
Takayuki Osuki ◽  
Hidenori Okamura ◽  
Shigeki Sasaki ◽  
...  
Keyword(s):  
Nucleoside Analogues ◽  
Triplex Dna ◽  
Parallel Type

scholarly journals Radical Dehalogenation and Purine Nucleoside Phosphorylase E. coli: How Does an Admixture of 2′,3′-Anhydroinosine Hinder 2-fluoro-cordycepin Synthesis

Biomolecules ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 539
Author(s):  
Alexey L. Kayushin ◽  
Julia A. Tokunova ◽  
Ilja V. Fateev ◽  
Alexandra O. Arnautova ◽  
Maria Ya. Berzina ◽  
...  
Keyword(s):  
Nmr Spectroscopy ◽  
Chemical Synthesis ◽  
Purine Nucleoside Phosphorylase ◽  
Purine Nucleoside ◽  
Preparative Synthesis ◽  
Nucleoside Phosphorylase ◽  
E Coli ◽  
First Time

During the preparative synthesis of 2-fluorocordycepin from 2-fluoroadenosine and 3′-deoxyinosine catalyzed by E. coli purine nucleoside phosphorylase, a slowdown of the reaction and decrease of yield down to 5% were encountered. An unknown nucleoside was found in the reaction mixture and its structure was established. This nucleoside is formed from the admixture of 2′,3′-anhydroinosine, a byproduct in the preparation of 3-′deoxyinosine. Moreover, 2′,3′-anhydroinosine forms during radical dehalogenation of 9-(2′,5′-di-O-acetyl-3′-bromo- -3′-deoxyxylofuranosyl)hypoxanthine, a precursor of 3′-deoxyinosine in chemical synthesis. The products of 2′,3′-anhydroinosine hydrolysis inhibit the formation of 1-phospho-3-deoxyribose during the synthesis of 2-fluorocordycepin. The progress of 2′,3′-anhydroinosine hydrolysis was investigated. The reactions were performed in D2O instead of H2O; this allowed accumulating intermediate substances in sufficient quantities. Two intermediates were isolated and their structures were confirmed by mass and NMR spectroscopy. A mechanism of 2′,3′-anhydroinosine hydrolysis in D2O is fully determined for the first time.

Synthesis of novel racemic carbocyclic nucleoside analogues derived from 4,8-dioxatricyclo[4.2.1.03,7]nonane-9-methanol and 4-oxatricyclo[4.3.1.03,7]decane-10-methanol, compounds with activity against Coxsackie viruses

2009 ◽  
Vol 74 (3) ◽  
pp. 469-485 ◽  
Author(s):  
Hubert Hřebabecký ◽  
Martin Dračínský ◽  
Armando M. De Palma ◽  
Johan Neyts ◽  
Antonín Holý
Keyword(s):  
Alder Reaction ◽  
Diels Alder ◽  
Purine Nucleoside ◽  
Nucleoside Analogues ◽  
Lithium Aluminium Hydride ◽  
Subsequent Reduction ◽  
Lithium Aluminium ◽  
Diels Alder Reaction ◽  
Carbocyclic Nucleoside ◽  
Carbocyclic Nucleoside Analogues

(1R*,2R*,3R*,4S*)-7-Oxabicyclo[2.2.1]hept-5-ene-2,3-dimethanol (10) and (1R*,2R*,3R*,4S*)-bicyclo[2.2.2]oct-5-ene-2,3-dimethanol (14), which were prepared by the Diels–Alder reaction and subsequent reduction with lithium aluminium hydride, were treated with benzyl azidoformate to give benzylN-[(1R*,2R*,3S*,6S*,7S*,9S*)-9-(hydroxymethyl)-4,8-dioxatricyclo[4.2.1.03,7]nonan-2-yl]carbamate (11) and benzylN-[(1R*,2R*,3R*,6R*,7S*,10S*)-10-(hydroxymethyl)-4-oxatricyclo[4.3.1.03,7]decan-2-yl]carbamate (15). Hydrogenolysis of carbamates11or15afforded (1R*,2R*,3S*,6S*,7S*,9S*)-2-amino-4,8-dioxatricyclo[4.2.1.03,7]nonane-9-methanol (12) or (1R*,2R*,3R*,6R*,7S*,10S*)-2-amino-4-oxatricyclo[4.3.1.03,7]decane-10-methanol (16). The amines12and16were transformed to thymine and purine nucleoside analogues. The target compounds were tested for the activity againstCoxsackievirus.

Fault Detection by Using Instance Segmentation

2021 ◽  
Author(s):  
Donglin Zhu ◽  
Lei Li ◽  
Rui Guo ◽  
Shifan Zhan
Keyword(s):  
Fault Detection ◽  
Seismic Data ◽  
Semantic Segmentation ◽  
Data Interpretation ◽  
Machine Learning Methods ◽  
Segmentation Algorithms ◽  
Direct Recognition ◽  
First Time ◽  
Seismic Images ◽  
Instance Segmentation

Abstract Fault detection is an important, but time-consuming task in seismic data interpretation. Traditionally, seismic attributes, such as coherency (Marfurt et al., 1998) and curvature (Al-Dossary et al., 2006) are used to detect faults. Recently, machine learning methods, such as convolution neural networks (CNNs) are used to detect faults, by applying various semantic segmentation algorithms to the seismic data (Wu et al., 2019). The most used algorithm is U-Net (Ronneberger et al., 2015), which can accurately and efficiently provide probability maps of faults. However, probabilities of faults generated by semantic segmentation algorithms are not sufficient for direct recognition of fault types and reconstruction of fault surfaces. To address this problem, we propose, for the first time, a workflow to use instance segmentation algorithm to detect different fault lines. Specifically, a modified CNN (LaneNet; Neven et al., 2018) is trained using automatically generated synthetic seismic images and corresponding labels. We then test the trained CNN using both synthetic and field collected seismic data. Results indicate that the proposed workflow is accurate and effective at detecting faults.

scholarly journals 2-Chloro-2′-deoxyadenosine monophosphate residues in DNA enhance susceptibility to 3′ → 5′ exonucleases

1994 ◽  
Vol 302 (2) ◽  
pp. 567-571 ◽  
Author(s):  
P Hentosh ◽  
P Grippo
Keyword(s):  
Dna Polymerase ◽  
Nucleoside Analogues ◽  
Duplex Dna ◽  
Exonuclease Activity ◽  
Klenow Fragment ◽  
Purine Nucleotide ◽  
Nucleotide Analogue ◽  
Pyrimidine Dimers ◽  
Deoxyadenosine Triphosphate ◽  
Dna Polymerase Ii

2-Chloro-2′-deoxyadenosine triphosphate, a purine nucleotide analogue and potent antileukaemic agent, was incorporated into double-stranded 36-mers in place of dATP to investigate the effects of 2-chloroadenine (ClAde) on DNA polymerase-associated 3′-->5′ exonuclease activity. ClAde residues within one strand of duplex DNA did not inhibit exonuclease activity; on the contrary, ClAde-containing minus strands were digested to a greater extent than was control DNA in the absence of deoxyribonucleoside triphosphates by Escherichia coli Klenow fragment, yeast DNA polymerase II and T4 DNA polymerase. After a 30 min incubation with 5 units of Klenow fragment, approximately 65% of control DNA remained in DNA fragments of 26 bases or larger compared with only approximately 25% of ClAde-substituted substrates. Unsubstituted plus strands opposite a ClAde-containing strand were likewise digested more quickly by 3′-->5′ exonuclease, but only in the vicinity of the ClAde sites. Approx. 63% of the plus strands from ClAde-containing oligomers were less than 24 bases in length after a 25 min digestion period with Klenow fragment compared with only approximately 32% of control DNA. Such results indicate that, unlike other base modifications such as pyrimidine dimers, methoxy psoralen adducts and certain nucleoside analogues, all of which inhibit or decrease the rate of strand degradation by 3′-->5′ exonucleases, incorporated ClAde enhances strand degradation of duplex DNA.

Valproate synergizes with purine nucleoside analogues to induce apoptosis of B-chronic lymphocytic leukaemia cells

2009 ◽  
Vol 144 (1) ◽  
pp. 41-52 ◽  
Author(s):  
Amel Baya Bouzar ◽  
Mathieu Boxus ◽  
Julien Defoiche ◽  
Guy Berchem ◽  
Derek Macallan ◽  
...  
Keyword(s):  
Chronic Lymphocytic Leukaemia ◽  
Lymphocytic Leukaemia ◽  
Purine Nucleoside ◽  
Nucleoside Analogues
Sign in / Sign up

Export Citation Format

Share Document