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1.
Abstract Facile and efficient 5′-bromination and 5′-iodination of unprotected nucleosides, such as uridine, thymidine, 5-ethyluridine, inosine, cytidine and adenosine, were achieved by the use of carbon tetrahalide and triphenylphosphine in N,N-dimethylacetamide or hexamethyl-phosphoramide. 相似文献
2.
Yukio Aoyama Takeshi Sekine Yoshiaki Iwamoto Etsuko Kawashima Yoshiharu Ishido 《Nucleosides, nucleotides & nucleic acids》2013,32(1-3):733-738
Abstract Efficient syntheses of 2′-bromo-2′-deoxy-3′,5′-O-TPDS-uridine (5a) and 1-(2-bromo-3,5-O-TPDS-β-D-ribofuranosyl)thymine (5b) from uridine and 1-(β-D-ribofuranosyl)thymine are described, respectively. The key step is a treatment of 3′,5′-O-TPDS-O2,2′-anhydro-1-(β-D-ardbinofuranosyl)uracil (4a) and -thymine (4b) with LiBr in the presence of BF3-OEt2 in 1,4-dioxane at 60°C to give 5a and 5b in 98%, and 96% yield, respectively. 相似文献
3.
Danny P. C. McGee Chandra Vargeese Yansheng Zhai Gary P. Kirschenheuter Alecia Settle Colleen R. Siedem 《Nucleosides, nucleotides & nucleic acids》2013,32(6):1329-1339
Abstract The synthesis of 2′-amino-2′-deoxypyrimidine 5′-triphosphates is described. The 2′-amino-2′-deoxyuridine 5′-triphosphate is obtained from uridine in four steps with 25% overall yield. The 2′-amino-2′-deoxycytidine 5′-triphosphate is obtained from uridine in seven steps with 13% overall yield. 相似文献
4.
《Nucleosides, nucleotides & nucleic acids》2013,32(1):13-19
Abstract Microwave-induced synthesis of O′-adamantyl derivatives of AZT, thymidine, 2′-deoxyuridine and uridine was investigated. Contrary to heterocyclus adamantylation of uracil and uridine in trifluoroacetic acid, the microwave-induced reaction provided sugar-substituted compounds. 相似文献
5.
Hiromichi Tanaka Hiroki Kumamoto Satoru Shindoh Hiroyuki Hayakawa Keisuke Kato Tadashi Miyasaka 《Nucleosides, nucleotides & nucleic acids》2013,32(4-5):585-586
Abstract Two examples of anionic stannyl migration practically useful for nucleoside synthesis are presented. One involves the migration from the 8- to 2-position of 6-chloropurine derivatives, which provided a new entry to 2-substituted purine nucleosides. The other is that from the 6- to 2′-position of 1′,2′-unsaturated uridine. The latter enabled the preparation of a hitheroto unknown class of nucleoside analogues, 2′-substituted 1′,2′-unsaturated uridines. 相似文献
6.
Kazuhiro Haraguchi Shigeru Saito Hiromichi Tanaka Tadashi Miyasaka 《Nucleosides, nucleotides & nucleic acids》2013,32(2-4):483-493
Abstract Pummerer-type rearrangement of uracil nucleosides having a phenylseleno group in the 2′-, 3′-, and 5′-positions took place upon oxidation with MCPBA in CH2Cl2 followed by treatment with acid anhydrides to yield α-acyloxyselenides. 相似文献
7.
Yuichi Yoshimura Fumitaka Kano Shuichi Miyazaki Noriyuki Ashida Shinji Sakata Kazuhiro Haraguchi 《Nucleosides, nucleotides & nucleic acids》2013,32(1-3):305-324
Abstract 2′-Deoxy-, 2′-bromo-, and arabino-1′-C-cyano-pyrimidine nucleosides were synthesized from O2 ,2′-cyclouridine. Incorporation of cyano group at the anomeric position was achieved by treatment of 1′,2′-unsaturated uridine with NBS in the presence of pivalic acid followed by TMS-cyanide and stannic chloride. Antineoplastic and antiviral activities of those compounds are also discussed. 相似文献
8.
《Nucleosides, nucleotides & nucleic acids》2013,32(5-8):1321-1325
Abstract Transformation of 2′-deoxyuridine and uridine analogs to protected 2′-deoxycytidine and cytidine analogs has been investigated by two different methods. First, traditional triazolation protocol and second p-nitrophenoxylation method. Our studies conclude that the triazolation method is better and suitable for commercial scale--up. 相似文献
9.
Ling-Ching Chen Tsann-Long Su Krzysztof W. Pankiewicz Kyoichi A. Watanabe 《Nucleosides, nucleotides & nucleic acids》2013,32(7):1179-1188
Abstract In an attempt to introduce a substituent at C-2′ in the “up” arabino configuration directly by nucleophilic displacement reaction of a preformed pyrimidine ribonucleoside, we synthesized 2,5′-anhydro-5′-deoxy-2-thiouridine (6) in three steps from uridine. Compound 6 was converted into the 3′-O-acetyl derivative 7. Upon treatment of 7 with triflyl chloride in methylene chloride in the presence of triethylamine and p-dimethylaminopyridine, 2,2′-anhydro-1-(3-O-acetyl-5-chloro-2,5-dideoxy-β-D-arabinofuranosyl)-2-thiouracil (9) was obtained as the only isolable product. Obviously, the intermediate 3′-O-acetyl-2,5′-anhydro-2′-O-triflyl-2-thiouridine (8) was attacked by the chloride nucleophile at C-5′ first giving the 2′-O-triflyl-2-thiouridine intermediate from which 9 was formed by intramolecular nucleopilic reaction. 相似文献
10.
Abstract Reactions using tri-n-butylphosphine and dialkyldisulfides have been investigated for the synthesis of several types of thiosugar nucleosides. Thus the reaction of N6-benzoyl-2′, 3′-O-isopropylideneadenosine with a large excess of diisobutyldisulfide leads, after simple deprotection, to the transmethylation inhibitor SIBA (3) in quite good yield. Using limiting amounts of disulfide, the reaction leads instead to a pyrimidine ring-opened cyclonucleoside (11). The hydrate of 2′, 3′-O-cyclohexylideneuridine 5′-aldehyde reacts with the same reagents to give a 77% yield of the corresponding diisobutyl dithioacetal. The hydrate of N6-benzoyl-2′, 3′-O-isopropylideneadenosine 5′-aldehyde, however, gave only a single diastereomer of the 5′-alkylthio derivative of 11. 相似文献
11.
Pawel J. Serafinowski Colin L. Barnes 《Nucleosides, nucleotides & nucleic acids》2013,32(7-9):1529-1532
Abstract The one step reaction of 2′- and 3′-keto derivatives of uridine with bromodifluoromethyl[tris(dimethylamino)]phosphonium bromide and zinc gives the corresponding 2′- and 3′-difluoromethylene nucleosides in good yield. Desilylation and phosphitylation of the resultant 2′- or 3′-hydroxyls provides the target 2′- and 3′-phosphoramidites 7 and 8 for use in oligonucleotide synthesis1. 相似文献
12.
Nucleosides VI: A Novel and Convenient Synthesis of Purine S-Cyclonucleosides Via Mitsunobu Reaction
Ji-Wang Chern Chia-Chi Kuo Ming-Jyh Chang Lee-Tai Liu 《Nucleosides, nucleotides & nucleic acids》2013,32(9):941-949
Abstract Two representative S-cyclonucleosides, 8,5′-anhydro-2′, 3′-O-isopropylidene-8-mercaptoadenosine (3) and 8,2′-anhydro-3′,5′-O-(tetraisopropyldisiloxane-1,3-diyl)-8-mercaptoguanosine (8), were prepared in good yields by dropwise addition of one equivalent each of triphenylphosphine and DEAD in DMF into a mixture of 2′,3′-O-isopropylidene-8-mercaptoadenosine (2) or 3′,5′-O-(tetra-iso-propyldisiloxane-1,3-diyl)-8-mercaptoguanosine (7), respectively, in DMF. Treatment of compound 2 with two equivalents each of triphenylphosphine and DEAD in DMF afforded N-[8,5′-anhydro-2′,3′-O-isopropylidene-8-mercaptopurin-6-yl]triphenylphospha-λ5-azene (4) in 87% yield. 相似文献
13.
Abstract 2-Aminoadenosine, obtained by silylation-amination from guanosine, is readily converted by KNO2/ HF/Pyridine in up to 80% yield into 2-fluoradenosine, which is a convenient starting material for the preparation of 9(β-D-arabinofuranosyl)-2-fluoroadenine 5′-phosphate (Fludara). N6N6-Pentamethylene-2-aminoadenosine and guanosine afford likewise the corresponding 2-fluoropurine nucleosides in high yields. 相似文献
14.
Christine Knies Gabriel Bonaterra Katharina Hammerbacher Andrea Cordes Ralf Kinscherf Helmut Rosemeyer 《化学与生物多样性》2015,12(12):1902-1944
A series of nucleolipids, containing one of the β‐D ‐ribonucleosides 5‐fluorouridine, 6‐azauridine, uridine, or 5‐methyluridine were lipophilized, either at the O‐2′,3′‐position and/or at N(3) of the nucleobase with a large variety of hydrophobic residues. The resulting nucleolipids as well as the parent nucleosides and the lipid precursors were investigated in vitro with respect to their antitumor activity towards i) ten human tumor cell lines from the NCI 60 panel and ii) partly against three further tumor cell lines, namely a) human astrocytoma/oligodendro glioma GOs‐3, b) rat malignantneuroectodermal BT4Ca, and c) differentiated human THP‐1 macrophages. Inspection of the dose response curves allows two main conclusions concerning lipid determinants lending the corresponding nucleoside an ameliorated or an acquired antitumor activity: i) introduction of either a symmetrical O‐2′,3′‐nonadecylidene ketal group or introduction of an O‐2′,3′‐ethyl levulinate moiety plus an N(3)‐farnesyl group leads often to nucleolipids with significant cytostatic/cytotoxic properties; ii) for the two canonical and non‐toxic nucleosides uridine and 5‐methyluridine, the condensation with also non‐toxic lipids gives nucleolipids with a pronounced antitumor activity. 相似文献
15.
R. Thomas Solsten James A. Mccloskey Karl H. Schram 《Nucleosides, nucleotides & nucleic acids》2013,32(1):57-64
Abstract A facile method for the synthesis of highly enriched 18O labeled pyrimidine ribonucleosides is described using uridine as a model compound. The isotopic label may be selectively incorporated into the base moiety at O2 or into the ribose portion of the molecule at the 5′ position. In addition, both positions may be labeled and this is the first report of a method for labeling of both the base and sugar moieties of pyrimidine ribonucleosides. The site and level of isotope incorporation may be determined mass spectrometrically. 相似文献
16.
Jasenka Matulic-Adamic Peter Haeberli Anthony B. DiRenzo Victor R. Mokler Lara Maloney Leonid Beigelman 《Nucleosides, nucleotides & nucleic acids》2013,32(10-11):1933-1950
Abstract Novel 5′-amino-5′-deoxy-2′-O-methyl uridine, guanosine and adenosine 3′-O-phosphoramidites 5, 11, and 20, as well as protected 5′-mercapto-5′-deoxy-2′-O-methyl uridine 3′-O-phosphoramidite 23 were synthesized from 2′-O-methyl nucleosides. These analogs were incorporated at the 5′-ends of hammerhead ribozymes to evaluate achiral bridging 5′-N- phosphoramidates and 5′-S-phosphorothioates as alternatives for non- bridging phosphorothioates commonly used for end stabilization against nucleases. Oligonucleotide synthesis and deprotection conditions were optimized for better yields of these modified ribozymes. 相似文献
17.
Abstract The syntheses of 5-(2, 2, 2-trifluoroethoxy)uracil, 5-(2, 2, 2-trifluoroethoxy)arabinouridine and 5-(2, 2, 2-trifluoroethoxy) uridine are described. 相似文献
18.
Stephen H. Kawai Jik Chin George Just 《Nucleosides, nucleotides & nucleic acids》2013,32(8):1045-1060
Abstract The synthesis of strategically protected nucleosides bearing β-mercaptoethyl chains at the α-C-3′ position from 1,2-di-O-acetyl-2′-S-acetyl-5-t?butyldiphenylsilyl-3-deoxy-3-C-(2′-mercaptoethyl)-α-D-ribofuranose 1 is described. It was found that treatment of the 5-O-methanesulfonyl sugar 19 or nucleoside 5 with either benzylmercaptan or methoxide resulted in rapid cleavage of the thiolester followed by intramolecular cyclization. This was used to prepare the novel trans?fused oxathiahydrindane nucleosides 7 and 27 as well as the cAMP analogue 29. 相似文献
19.
S. Juntunen H. Essadiq A. Grouiller J. Chattopadhyaya 《Nucleosides, nucleotides & nucleic acids》2013,32(1-2):187-189
Abstract New routes to the preparations of 2′-deoxy-3′-C-methyl uridine (2c) and 1-(5′-0-trityl-3′-deoxy-β-D-glycero-pentofuran-2-ulosyl)uracil (4) from 5′-0-trityl-2′-0-tosyl uridine (1) and 5′-0-trityl-3′-0-tosyl uridine (3) respectively are described. 相似文献
20.
Peihua Shang Hua Wang Changmei Cheng Hongchao Zheng Yufen Zhao 《Nucleosides, nucleotides & nucleic acids》2013,32(12):1272-1281
A general method is described for synthesizing 3′,5′-dithio-2′-deoxypyrimidine nucleosides 6 and 13 from normal 2′-deoxynucleosides. 2,3′-Anhydronucleosides 2 and 9 are applied as intermediates in the process to reverse the conformation of 3′-position on sugar rings. The intramolecular rings of 2,3′-anhydrothymidine and uridine are opened by thioacetic acid directly to produce 3′-S-acetyl-3′-thio-2′-deoxynucleosides 3 or 5. To cytidine, OH? ion exchange resin was used to open the ring and 2′-deoxycytidine 10 was abtained in which 3′-OH group is in threo-conformation. The 3′-OH is activated by MsCl, and then substituted by potassium thioacetate to form the S,S′-diacetyl-3′,5′-dithio-2′-deoxycytidine 12. The acetyl groups in 3′,5′ position are removed rapidly by EtSNa in EtSH solution to afford the target molecules 6 and 13. The differences of synthetic routes between uridine and cytidine are also discusssed. 相似文献