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11.
《Nucleosides, nucleotides & nucleic acids》2013,32(5-8):1035-1038
Abstract Synthesis of 2′-fluoro-nucleosides from L-arabinose in order to perform the synthesis of 2′-fluoro-Spiegelmers binding to a neuropeptide. 相似文献
12.
Melinda Nonn Loránd Kiss Mikko M. Hänninen Reijo Sillanpää Ferenc Fülöp 《化学与生物多样性》2012,9(11):2571-2581
Fluorinated highly functionalized cispentacin derivatives were synthetised starting from an unsaturated bicyclic β‐lactam through C?C bond functionalization via the dipolar cycloaddition of a nitrile oxide, isoxazoline opening, and fluorination by OH/F exchange. 相似文献
13.
Reuben Ovadia Ahmed Khalil Hao Li Coralie De Schutter Seema Mengshetti Shaoman Zhou Leda Bassit Steven J. Coats Franck Amblard Raymond F. Schinazi 《Bioorganic & medicinal chemistry》2019,27(4):664-676
We report herein the synthesis and evaluation of a series of β-d-2′-deoxy-2′-α-chloro-2′-β-fluoro and β-d-2′-deoxy-2′-α-bromo-2′-β-fluoro nucleosides along with their corresponding phosphoramidate prodrugs. Key intermediates, lactols 11 and 12, were obtained by a diastereoselective fluorination of protected 2-deoxy-2-chloro/bromo-ribonolactones 7 and 8. All synthesized nucleosides and prodrugs were evaluated with a hepatitis C virus (HCV) subgenomic replicon system. 相似文献
14.
Clement Q. Fontenelle Zhong Wang Christine Fossey Thomas Cailly Bruno Linclau Frederic Fabis 《Bioorganic & medicinal chemistry》2013,21(23):7529-7538
Analogues of potent 5-HT4R antagonists possessing a fluorinated N-alkyl chain have been synthesized in order to investigate the effect of the resulting change in basicity and lipophilicity on the affinity and selectivity profile. We demonstrate that for this series, the affinity is decreased with decreased basicity of the piperidine’s nitrogen atom. In contrast, the resulting increase in lipophilicity has minimal impact on binding affinity and selectivity. 3,3,3-Trifluoropropyl and 4,4,4-trifluorobutyl derivatives 6d and 6e have shown to bind to the 5-HT4R while maintaining their pharmacological profile and selectivity toward other 5-HT receptors. 相似文献
15.
《Bioorganic & medicinal chemistry》2014,22(19):5168-5181
Sphingosine-1-phosphate (S1P) receptors play major roles in cardiovascular, immunological and neurological diseases. The recent approval of the sphingolipid drug Fingolimod (Gilenya®), a sphingosine-1-phosphate agonist for relapsing multiple sclerosis, in 2010 exemplifies the potential for targeting sphingolipids for the treatment of human disorders. Moreover, non-invasive in vivo imaging of S1P receptors that are not available till now would contribute to the understanding of their role in specific pathologies and is therefore of preclinical interest. Based on fluorinated analogues of the S1P1 receptor antagonist W146 showing practically equal in vitro potency as the lead structure, the first S1P receptor antagonist [18F]-radiotracer has been synthesized and tested for in vivo imaging of the S1P1 receptor using positron emission tomography (PET). Though the tracer is serum stable, initial in vivo images show fast metabolism and subsequent accumulation of free [18F]fluoride in the bones. 相似文献
16.
《Nucleosides, nucleotides & nucleic acids》2013,32(5-8):507-517
Abstract Two industrial synthetic approaches to Lodenosine (1, FddA, 9-(2,3-dideoxy- 2-fluoro-β-D-threo-pentofuranosyl) adenine) via a purine riboside or a purine 3′-deoxyriboside are described. Several novel applications of deoxygenation and fluorination methods are compared considering reaction yields, economy, safety and environmental concerns. 相似文献
17.
Reactions of dicarbaphosphazenes with N-methyl imidazole and fluoride ion have been studied. In contrast to earlier observations of dealkylation reactions, these reactions with imidazole led to quaternized products. Attempted fluorination of dicarbaphosphazene led to rupture of the phosphazene ring explaining the non-existence of fluorinated analog of carbaphosphazenes. 相似文献
18.
The synthesis and NMR characterizations of 1,2,3,6-tetra-O-benzoyl-4-deoxy-4-fluoro-β-d-galactopyranoside, the 4-deoxy-4-fluoro epimer of an intermediate in the synthesis of a drug substance, needed for use as a potential impurity standard and to confirm the stereoselectivity of a key fluorination step, are described. 相似文献
19.
Cristina Y. Zamora Marc d’Alarcao Krishna Kumar 《Bioorganic & medicinal chemistry letters》2013,23(11):3406-3410
Herein we report the synthesis of N-acetyl neuraminic acid derivatives as 4-methylumbelliferyl glycosides and their use in fluorometrically quantifying human and bacterial sialidase activity and substrate specificities. We found that sialidases in the human promyelocytic leukemic cell line HL60 were able to cleave sialic acid substrates with fluorinated C-5 modifications, in some cases to a greater degree than the natural N-acetyl functionality. Human sialidases isoforms were also able to cleave unnatural substrates with bulky and hydrophobic C-5 modifications. In contrast, we found that a bacterial sialidase isolated from Clostridium perfringens to be less tolerant of sialic acid derivatization at this position, with virtually no cleavage of these glycosides observed. From our results, we conclude that human sialidase activity is a significant factor in sialic acid metabolic glycoengineering efforts utilizing unnatural sialic acid derivatives. Our fluorogenic probes have enabled further understanding of the activities and substrate specificities of human sialidases in a cellular context. 相似文献
20.
Christine Kaduk Holger Wenschuh Michael Beyermann Klaus Forner Louis A. Carpino Michael Bienert 《Letters in Peptide Science》1996,2(5):285-288
Summary DAST [(diethylamino)sulfur trifluoride] has shown to be an excellent alternative fluorinating agent for synthesis of Fmoc-amino acid fluorides. The use of DAST is advantageous relative to other fluorinating agents, such as cyanuric fluoride, since handling and isolation of the acid fluorides are facile. 相似文献