- Voltammetric study of the affinity of divalent heavy metals for guanine-functionalized iron oxide nanoparticles
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In this study, a novel nanobiomaterial based on (3-aminopropyl)triethoxysilane (APTES)-coated iron oxide (Fe3O4) nanoparticles functionalized with newly synthesized guanine hydrazide (GH) was elaborated. A boron-doped diamond electrode coated with GH-APTES–Fe3O4 nanoparticles was used to assess the interaction of heavy metal ions with guanine hydrazide. The adsorption isotherms were electrochemically investigated and it was shown that the adsorption capacity of the nanoparticles towards heavy metals decreased in the following order: Cu2+ > Pb2+ > Cd2+. From the calibration curves, the sensitivities of detection were as follows: 171.6 μA/μM for Cu(II), 156 μA/μM for Pb(II), and 101.4 μA/μM for Cd(II). Graphic abstract: [Figure not available: see fulltext.].
- Sawan, Simona,Hamze, Khalil,Youssef, Ali,Boukarroum, Rayyan,Bouhadir, Kamal,Errachid, Abdelhamid,Maalouf, Rita,Jaffrezic-Renault, Nicole
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p. 229 - 240
(2021/02/12)
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- Preparation method of N2,9-diacetylguanine
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The invention belongs to the technical field of chemistry, and in particular, relates to a preparation method of N2,9-diacetylguanine. The method comprises the steps: A, dissolving guanine in pyridine under the condition of stirring, then adding a 4-dimethylamino pyridine DMAP catalyst into a guanine pyridine solution, cooling to -5+/-1 DEG C, slowly dropping an acylating agent acetyl chloride, and in the dropping process, controlling the temperature to be lower than 10 DEG C; and after dropping is finished, carrying out a reaction for 2-4 h at room temperature, to obtain an X1-containing reaction liquid; B, heating the X1 reaction liquid, carrying out reduced pressure distillation to remove substances X2 and X3, and separating out an X1-containing solid; C, washing the X1-containing solid obtained in the step B with distilled water, and filtering to remove X4 and X5; and D, dissolving the X1-containing solid obtained in the step C in an acetic acid solution through stirring, and filtering to remove an undissolved substance X6, to obtain an X1-containing filtrate. The total yield of N2,9-diacetylguanine reaches 90.2%, and the purity of the product reaches 99.5%.
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Paragraph 0027; 0028; 0029; 0030; 0031; 0032
(2017/06/02)
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- Small Molecules in the Cone Snail Arsenal
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Cone snails are renowned for producing peptide-based venom, containing conopeptides and conotoxins, to capture their prey. A novel small-molecule guanine derivative with unprecedented features, genuanine, was isolated from the venom of two cone snail species. Genuanine causes paralysis in mice, indicating that small molecules and not just polypeptides may contribute to the activity of cone snail venom.
- Neves, Jorge L. B.,Lin, Zhenjian,Imperial, Julita S.,Antunes, Agostinho,Vasconcelos, Vitor,Olivera, Baldomero M.,Schmidt, Eric W.
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supporting information
p. 4933 - 4935
(2015/11/03)
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- Synthesis of some biologically active halogenopurines
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A series of some biologically active halogenopurines were synthesized from commercially available guanine (1). The reaction of guanine with acetic anhydride yielded 2,9-diacetylguanine (2-1) by acetylation reaction. Further treatment of 2-1 with POCl3 by PEG-2000 phase transfer catalysis furnished the important compound 3a, then 2-amino-6-halogenopurines (3b-d) were obtained through chlorine-exchange halogenations between KX and 3a by TPPB phase transfer catalyst. Further, 2-halogenopurines (2-2a-d, 4-2a-d, 5a-d) were efficiently prepared from 2-amino-6-substituted purines (1, 3a, 4-1) via a diazotization catalyzed by their corresponding CuX, and some new compounds 2-2a, 2-2c, 2-2d, 4-2c, 4-2d, 5b, 5c and 5d have been discovered. The structures of synthesized compounds were mainly established on the basis of their elemental analysis, 1H NMR, as well as their mass spectral data. All the title compounds were screened for their antifungal activities, and some of the compounds showed promising activity.
- Hu, Yu Lin,Liu, Xiang,Lu, Ming,Ge, Qiang,Liu, Xiao Bin
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experimental part
p. 429 - 436
(2010/12/29)
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- Synthesis and biological activities of O6-alkylguanine derivatives
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The synthesis of some biologically active O6-alkylguanine derivatives was achieved by alkoxylation of 2-amino-6-chloropurine with sodium alkoxides in polar aprotic solvent (DMSO) conditions. The starting material 2-amino-6-chloropurine was prepared by chlorination of 2,9-diacetylguanine (obtained from acetylation of commercially available guanine) by PEG-2000 phase transfer catalysis. The structures of the products were deduced from elemental analysis and spectral data (IR, 1H NMR, and mass spectra). All the title compounds were screened for their antifungal activities, and some of the compounds showed promising activities.
- Hu, Yu Lin,Ge, Qiang,Lu, Ming,Lu, Hong Fei
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experimental part
p. 425 - 432
(2012/01/13)
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- Guanine-Containing DNA Minor-Groove binders
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Solid-phase procedures have been used to prepare six di-pyrrole-containing DNA ligands that combine (guanin-9-yl)-acetyl, (guanin-7-yl)acetyl or acetyl moieties at the N-terminal end and two lysines or a (dimethylamino)propyl group at the C terminus. Inspection of their DNA-stabilizing properties by UV-monitored thermal denaturation experiments showed that the ligand incorporating the (guanin-9-yl)acetyl group and the (dimethylamino)propyl tail had the highest duplex-stabilizing effects. Wiley-VCH Verlag GmbH & Co, KGaA.
- Pulido, Daniel,Sanchez, Albert,Robles, Jordi,Pedroso, Enrique,Grandas, Anna
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experimental part
p. 1398 - 1406
(2009/08/07)
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- Engineering a selective small-molecule substrate binding site into a deoxyribozyme
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A small goal: An RNA ligase deoxyribozyme is engineered to accept a small-molecule NTP substrate in a multiple-turnover fashion. Selective binding is enforced by hydrogen bonding, and structural preorganization within the NTP itself is important for its efficient utilization as a substrate. This study points the way toward a broader use of small-molecule substrates with nucleic acid enzymes. (Figure Presented)
- Hoebartner, Claudia,Silverman, Scott K.
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p. 7420 - 7424
(2008/09/18)
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- Positively-charged peptide nucleic acid analogs with improved properties
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The present invention relates to novel types of peptide nucleic acids (PNAS) with improved properties. In particular, it relates to positively charged PNA units having an ethylene linker between the backbone and the nucleobase, to oligonucleotide analogs comprising these units, to oligomers comprising these units, and to the use of positively charged PNAs as novel delivery agents with therapeutic and diagnostic applications including for antisense therapy.
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Page/Page column 8-9
(2008/06/13)
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- A novel approach to the synthesis of the purine anti-viral agent gancyclovir
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The aim of this research is to synthesize gancyclovir, a purine anti-viral drug in large scale via simple intermediates. Reaction of guanine 1 with acetic anhydride followed by the attachment of the 2-O-acetoxymethyl-1,3-di-O-benzyl glycerol 3 as a side chain, subsequently lead to the production of N2acetyl-9-(1,3dibenzyloxy-2-propoxymethyl)guanine 6 and N2, acetyl-9-(1,3-dihydroxy-2-propoxymethyl)guanine 7 and finally synthesizing gancyclovir 8. Among many pathways to the synthesis of purine derivatives, our four step procedure results in good yield and is proved to be an economic way of large scale synthesis.
- Sariri, Reyhaneh,Khalili, Gholamhosein
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p. 651 - 654
(2007/10/03)
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- Regioselective synthesis of acyclovir and its various prodrugs
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High-yield regioselective synthesis of 9-[(2-hydroxyethoxy)methyl]guanine (Acyclovir 1, Scheme 1) was achieved from guanine via trisilylated guanine. N2-acylacyclovir 9a-9b were prepared from N2, O-diacylacyclovir (4, 8b-8d) using regioselective deacylation procedure. N2-Acylacyclovir 11 and 13 were prepared via protection of primary hydroxyl groups. Three amino acid esters of acyclovir were synthesized as water-soluble prodrugs, which form protonated cations in pH 7.4 phosphate buffer. Two water-soluble ester prodrugs with free carboxylic acids, which form anionic species in pH 7.4 phosphate buffer, were also synthesized.
- Gao,Mitra
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p. 1399 - 1419
(2007/10/03)
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- 9-Vinylguanine: An easy access to aza-analogs of 2′,3′-dideoxyguanosine
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9-Vinylguanine, obtained for the first time and fully characterised by X-ray analysis, allows access to aza-analogues of 2′,3′-dideoxynucleosides through cycloaddition processes.
- Dalpozzo, Renato,De Nino, Antonio,Maiuolo, Loredana,Procopio, Antonio,De Munno, Giovanni,Sindona, Giovanni
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p. 4035 - 4038
(2007/10/03)
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- N2-acetyl-O6-(2-(p-nitrophenyl)ethyl)guanine: A convenient building block for the synthesis of 9-substituted guanine derivatives
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Readily accessible N2-acetyl-O6-(2-(p-nitrophenyl)ethyl)guanine can undergo Mitsunobu reactions with either a primary or secondary alcohol to generate guanine derivatives. X-ray data indicates that only the desired 9- subsituted derivatives of guanine are formed.
- Zhou, Jinglan,Tsai, Jui-Yi,Bouhadir, Kamal,Shevlin, Philip B.
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p. 3003 - 3009
(2007/10/03)
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- Substituted 9-(1 or 3-monoacyloxy or 1,3-diacyloxy-2-propoxymethyl) purines as antiviral agent
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Compounds useful as antiviral agents are defined by the following formula: STR1 and the pharmaceutically acceptable acid addition salts thereof wherein R1 is hydrogen or --C(O)R7 wherein R7 is hydrogen, alkyl of one to nineteen carbon atoms, hydroxyalkyl of one to eight carbon atoms, alkoxyalkyl of two to nine carbon atoms, alkenyl of two to nineteen carbon atoms, phenyl, 1-adamantyl or 2-carboxyethyl and the pharmaceutically acceptable alkali metal salts thereof; R2 is --C(O)R7 wherein R7 is as defined above; R3 is hydrogen, halo, thio, lower alkylthio of one to six carbon atoms, azido, NR9 R10 wherein R9 and R10 are independently hydrogen or lower alkyl of one to six carbon atoms or --NHC(O)R8 wherein R8 is hydrogen, alkyl of one to nineteen carbon atoms or 1-adamantyl; and (a) R6 is hydrogen, halo, lower alkoxy of one to six carbon atoms, azido, thio, lower alkylthio of one to six carbon atoms, --NR9 R10 wherein R9 and R10 are as defined above or --NHC(O)R8 wherein R8 is as defined above and R4 together with R5 is a bond; or (b) R5 together with R6 is a keto group and R4 is hydrogen.
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- SYNTHESIS OF A NEW POTENTIAL ANTIVIRAL AGENT - 9-ALLYLOXYMETHYLGUANINE
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A convenient method has been developed for the synthesis of 9-allyloxymethylguanine. The direct alkylation of the trimethylsilyl derivative of guanine allyloxymethyl chloride gives a 64 percent yield of 9- and 7-allyloxymethylguanine (3:1). A mixture of 9- and 7-allyloxymethyl-N-acetylguanine (7:4) can be obtained in 56 percent yield by the condensation of diacetylguanine with allyloxymethyl acetate in dimethyl sulfoxide in the presences of p-toluenesulfonic acid.
- Ozerov, A. A.,Brel', A. K.
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p. 945 - 948
(2007/10/02)
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- Process for preparing guanine derivatives
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1-Monophosphate esters, 1,3-bisphosphate esters and cyclic phosphate esters of 9-(1,3-dihydroxy-2-propoxymethyl)guanine are useful as antiviral agents.
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- 9-(1,3-Dihydroxy-2-propoxymethyl)guanine as antiviral agent
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The compound 9-(1,3-dihydroxy-2-propoxymethyl)guanine and the pharmaceutically acceptable salts thereof are useful as antiviral agents.
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- 9-(1,3-Dihydroxy-2-propoxymethyl)guanine as antiviral agent
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The compound 9-(1,3-dihydroxy-2-propoxymethyl)guanine and the pharmaceutically acceptable salts thereof are useful as antiviral agents.
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