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1.
Sz. Lehel G. Horváth I. Boros P. Mikecz T. Márián L. Trón 《Journal of Radioanalytical and Nuclear Chemistry》2000,245(2):399-401
5-Deoxy-5-[18F]fluoro-adenosine was synthesised by nucleophilic radiofluorination reactions of 5-deoxy-5-haloadenosines. The homogeneous isotope exchange in 5-deoxy-5-fluoro-adenosine was also investigated. The conversion of these reactions was found to be rather low and depends on the strength of the halogen-carbon bond: 0.248% for chloride-, 0.488% for bromide- and 1.070% for iodide-derivative; there was no reaction observed in the case of fluoro-compound. 相似文献
2.
《Tetrahedron: Asymmetry》1999,10(11):2119-2127
A general synthetic approach to 2,3-unsaturated glycosides connecting with nucleosides involving Ferrier rearrangements of glycals is discussed. The new compounds were identified by NMR and MS (HRFAB+). The hydroxylation of the resulting 2,3-unsaturated glycosides was completed using OsO4 to give 5′-O-glycosylnucleosides in good yield. 相似文献
3.
Li Zhang Cai-Rong Zhou Zhong-Ping Liu Ming-Xing Huang 《Journal of Thermal Analysis and Calorimetry》2014,117(1):355-360
The melting temperature, melting enthalpy, and specific heat capacities (C p) of 5′-deoxy-5′-iodo-2′,3′-O-isopropylidene-5-fluorouridine (DIOIPF) were measured using DSC-60 Differential Scanning Calorimetry. The melting temperature and melting enthalpy were obtained to be 453.80 K and 33.22 J g?1, respectively. The relationship between the specific heat capacity and temperature was obtained to be C p/J g?1 K?1 = 2.0261 – 0.0096T + 2 × 10?5 T 2 at the temperature range from 320.15 to 430.15 K. The thermal decomposition process was studied by the TG–DTA analyzer. The results showed that the thermal decomposition temperature of DIOIPF was above 487.84 K, and the decomposition process can be divided into three stages: the first stage is the decomposition of impurities, the mass loss in the second stage may be the sublimation of iodine and thermal decomposition process of the side-group C4H2O2N2F, and the third stage may be the thermal decomposition process of both the groups –CH3 and –CH2OCH2–. The obtained thermodynamic basic data are helpful for exploiting new synthetic method, engineering design, and commercial process of DIOIPF. 相似文献
4.
《Tetrahedron letters》1987,28(23):2623-2626
2′-5′,3′-5′ Linked triadenylates have been synthesized by direct bisadenylylation of adenosine 2′ and 3′ hydroxyls with an adenosine 5′-phosphorochloridite followed by oxidation. 相似文献
5.
6.
Srilatha Avuluri Sheshurao Bujaranipalli Saibal Das J.S. Yadav 《Tetrahedron letters》2018,59(39):3547-3549
A first stereoselective total synthesis of 14-memebered β-resorcylic macrolactone 5′-hydroxyzearalenone (1) has been achieved. The key steps are Jocobsen hydrolytic kinetic resolution, Sharpless asymmetric dihydroxylation, Vilsmeier-Haack reaction, Mitsunobu esterification and ring-closing metathesis. 相似文献
7.
Uridine 5′-oxyphosphorane was synthesized by the reaction of 2′, 3′-di-O-acteyluridine 5′-diisopropyl phosphite with tetrachloro-1, 2-benzoquinone. 相似文献
8.
Summary 5 -Benzoyl-2 -hydroxychalcones were synthesized by the condensation of 5 -benzoyl-2 -hydroxyacetophenone with aromatic aldehydes in presence of an ethanolic solution of potassium hydroxide. Derivatives of 6-benzoylflavonoids were prepared from chalcones. 相似文献
9.
ZHAO Xing-Ea b SHANG Pei-Huab CHENG Chang-Meib② CHEN Lang-Qiua② WANG Ru-Jib ZHAO Yu-Fenb a 《结构化学》2008,(10)
In this paper=5′-O-tosyl-2,3′-anhydrothymidine has been synthesized and its crystal structure was analyzed. The crystal belongs to the triclinic system=space group P1=with a=5.397(2)=b=6.1886(18)=c=3.507(5) =α =87.74(2)=β =89.84(4)=γ =73.79(2)°=C17H18N2O6S=Mr=378.39=Z=1=V=432.8(3)3=Dc=1.452 g/cm3=F(000)=198 and Flack =-0.11(14). No intermolecular hydrogen bonds exist in the crystal=and the angle between benzene ring and pyrimidine planes is 32.23°. 相似文献
10.
《Tetrahedron letters》1986,27(13):1521-1522
Cleavage of 2−O-tetrahydropyranyl groups from ribonucleoside derivatives used in solid-phase oligoribonucleotide synthesis takes place to an unacceptable extent during treatment with protic acid to remove 5′-O-pixyl groups. 相似文献
11.
The synthesis of the title compound is described. The key-step is the photochemical coupling between 5-iodo-2-thienylcarbaldehyde and 2-bromothio-phene to give 5-bromo-2,2′-bithienyl-5′-carbaldehyde. 相似文献
12.
《液相色谱法及相关技术杂志》2012,35(11):2027-2039
Abstract HPLC has been used for the analysis and separation of the components of px (A2′p)n A (x = 1 to 3, n = 1 to ≥4). Weak anion exchange columns give excellent resolution, but their instability in phosphate buffers makes them impractical for routine use. Reverse phase chromatography using C18 columns provides a satisfactory alternative method. For preliminary analysis of crude material, ammonium phosphate pH7.0 with a linear 1:1 methanol/H2O gradient gives a good basic separation of the individual oligomers. Resolution of the 5′ mono-, di-and triphosphorylated oligomers or of the nonphosphorylated components can be obtained using ammonium phosphate pH6.0 and potassium phosphate pH6.5 buffers respectively. The C18 columns are very stable and any one column will give retention times reproducible within 0.2%. 相似文献
13.
Conditions were studied in the biosynthesis of cytidine 5′-triphosphate (CTP) from cytidine 5′-monophosphate (CMP). A 201 × 7
anion ion-exchange resin was applied for the separation of CTP from CMP. Adsorption isotherm and elution conditions (eluant,
eluant concentration, flow rate, sample volume loaded) were investigated. At the same time, a new high-performance liquid
chromatography on an anion ion-exchange column WAX-1 with UV detector at 260 nm was developed to measure CMP, cytidine 5′-diphosphate
(CDP), and CTP. The retention time for CMP, CDP, and CTP are 0.723, 1.448, and 4.432 min, respectively. This new rapid high-performance
liquid chromatography (HPLC) method for the analysis of cytidine compounds in biological sample has a wide linear range with
high precision and repeatability. 相似文献
14.
Geoffrey T. Crisp 《合成通讯》2013,43(11-12):2117-2123
The palladium-catalysed coupling of 3,5 Di-O-p-toluoyl-5-iodo-2′ -deoxyuridine with functionalized and non-functionalized alkenylstannanes gave moderate to good yields of the corresponding 5-alkenyl-2 -deoxyuridines. 相似文献
15.
《Tetrahedron letters》1986,27(15):1657-1660
A convenient and general method for the synthesis of nucleoside 3′,5′-cyclic phosphorothioates using nucleosides as starting materials is described.A synthesis of nucleoside 3′,5′-cyclic phosphorothioates is described. 相似文献
16.
《Tetrahedron letters》1988,29(10):1123-1126
A membrane-enclosed enzyme reactor containing adenylate kinase (E.C. 2.7.4.3, rabbit muscle) and pyruvate kinase (E.C. 2.7.1.40) converts cytidine 5′-monophosphate (CMP) and phosphoenolpyruvate (PEP) to cytidine 5′-triphosphate (CTP) and pyruvate on a gram scale. 相似文献
17.
Jeongki Kang Nguyen Anh Tuan Jong-Min Kim Sang-Mok Chang Woo-Sik Kim 《Applied biochemistry and biotechnology》2010,160(2):561-573
The present study used a mechanistic approach to control the phase transformation of guanosine 5′-monophosphate (GMP) via
the operating conditions of agitation and feed concentration during drowning-out crystallization. First, Fourier transform
infrared and UV/vis spectrophotometry were successfully applied to monitor the mass fraction of GMP polymorphs (amorphous
and hydrate crystalline GMPs) and GMP supersaturation, respectively, during the crystallization. The phase transformation
of amorphous GMP into hydrate crystals was significantly influenced by the agitation, which promoted the mass transfer of
GMP dissolution and growth. Therefore, the phase transformation was quickly finished when increasing the agitation speed.
However, a high agitation caused breakage of the hydrate crystals, resulting in a reduced crystal size with a bimodal distribution.
The phase transformation was also influenced by the GMP feed concentration, as the crystal growth was promoted and the crystal
size increased when increasing the feed concentration up to 61 g/l. However, a further increase in the feed concentration
caused secondary nucleation due to the induction of a high supersaturation level during the phase transformation, leading
to a small crystal size with a bimodal distribution. In addition, the rectangular-shaped hydrate GMP crystals exhibited a
higher growth rate in the b direction rather than the a direction. Therefore, the crystal morphology shifted from a long rectangle
to a square when increasing the feed concentration. 相似文献
18.
The reaction of ribonucleoside‐5′‐phosphoroimidazolide with a tributylammonium orthophosphate in anhydrous dimethylformamide at room temperature provides a general method for the synthesis of nucleoside‐5′‐diphosphates. The novelty of the approach is to use the triethylammonium salt of 5′‐monophosphate nucleoside derivative prior to the imidazolate reaction with imidazole, triphenylphosphine, and 2,2′‐dithiodipyridine. Deprotection, followed by displacement of the imidazole moiety using tributylammonium orthophosphate and a catalytic amount of zinc chloride in dimethylformamide gave the desired 5′‐diphosphate products. The triethyl ammonium salt of 5′‐diphosphate nucleosides was purified by flash chromatography using DEAE (diethylaminoethyl weak anion exchange resin) Sepharosa fast flow packed in an XK 50/60 column on an Akta FPLC (Fast Protein Liquid Chromatography). Synthesis procedures are reported for adenosine‐5′‐diphosphate, uridine‐5′‐diphosphate, cytidine‐5′‐diphosphate, and guanosine‐5′‐diphosphate. Yields for the displacement reactions ranged from 95 to 97%. Thus, this method offers the advantages of shorter reaction time, greater product yield, and a more cost‐effective synthetic route. 相似文献
19.
20.
《高等学校化学研究》2006,(6)
IntroductionIn recent years, nucleosides and their analogshave been extensively studied as potential anticancerand antiviral agents[1—3]. For example, several purineand pyridine bases and nucleoside analogs are used aschemotherapeutic arsenal. For their biological activity,these analogs should be intracellularly metabolized to5′-mononucleotides by kinase-mediated phosphoryla-tion[4]. To overcome the problemof drug resistance andto improve the membrane penetration, a series of aminoacid phosp… 相似文献