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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.
A. Yu. Mandzhulo N. A. Mel’nichuk V. N. Fetyukhin M. V. Vovk 《Russian Journal of Organic Chemistry》2016,52(1):87-91
N-Boc-protected 8-azaspiro[bicyclo[3.2.1]octane-3,2′-oxirane] reacted with primary aliphatic amines through opening of the epoxide ring with formation of the corresponding amino alcohols which were converted into N-chloroacetyl derivatives. The latter underwent cyclization to N-Boc-protected 4′-alkyl-8-azaspiro[bicyclo[3.2.1]octane-3,2′-morpholin]-5′-ones by the action of sodium hydride in DMF, and subsequent treatment with hydrogen chloride in ethyl acetate afforded 8-azaspiro[bicyclo[3.2.1]octane-3,2′-morpholin]-5′-one hydrochlorides. 相似文献
3.
The development of new catalyst-free green and efficient protocol to access 5′-thioxospiro[indoline-3,3′-[1,2,4]triazolidin]-2-ones/spiro[indoline-3,3′-[1,2,4]triazolidine]-2,5′-diones, potential privileged scaffolds for drug discovery, is disclosed. Key feature of this methodology is the dual use of glycerol—a recyclable, bioorganic compound, as a solvent cum promoter. Other highlights include use of inexpensive reagents, mild reaction conditions, operational simplicity, short reaction time, no need for chromatographic purification, and high yields. 相似文献
4.
4-chloroquinoline-3-carboxylates 2 and 5-mercapto-1,2,4-triazoles 3 have been cyclised to a novel heterocyclic system 4 . 相似文献
5.
Konovalova V. V. Shklyaev Yu. V. Maslivets A. N. 《Russian Journal of Organic Chemistry》2011,47(7):1119-1120
Russian Journal of Organic Chemistry - 相似文献
6.
V. E. Éman M. S. Sukhanov O. V. Lebedev L. V. Batog L. I. Khmel'nitskii 《Chemistry of Heterocyclic Compounds》1996,32(2):227-228
4,4-Diamino-3,3-azofurazane undergoes intramolecular oxidative cyclization to give 5-[4-amino(1,2,5)oxadiazolyl]-5H-[1,2,3]triazolo[4,5-c][1,2,5]oxadiazole upon heating with Pb(OAc)4 in chlorobenzene oro-dichlorobenzene or with thionyl chloride.Deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 253–254, February, 1996. 相似文献
7.
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
8.
The crystal structure of the title compound(C24H24N2O5, Mr = 420.45) has been determined by single-crystal X-ray diffraction. The crystal is of triclinic, space group P1 with a = 8.991(1), b = 11.166(1), c = 11.169(1) , α = 91.413(2), β = 105.887(2), γ = 90.992(2)°, V = 1077.8(2) 3, Z = 2, Dc = 1.296 g/cm3, F(000) = 444, μ(MoKα) = 0.091 mm-1, the final R = 0.0466 and wR = 0.1507 for 4185 observed reflections(I 2σ(I)). The single-crystal X-ray diffraction data indicated intermolecular C(17)–H(17)O(4), C(5)–H(5)… O(4) hydrogen bonds and C–H…π interaction in the structure. 相似文献
9.
3′O-silylated derivatives of 5′-O-DMT-2′deoxynucleoside (2) were synthesized in high yield by reaction of 5′-O-DMT-2′-deoxynucleosides (1) with tert-butyl dimethylsilylchloride using sodium hydride, benzyltriethylammonlum chloride [TEBA] and a catalytic amount of dibenzo-[18]-crown-6 [DB-18-C-6] or 15-crown-5 [15-C-51 under mild reaction conditions. 相似文献
10.
《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
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12.
3-[1′(1′H)-Substituent-pyrazol-5′-yl]benzo[5,6]coumarins and 3-(1′,2′-oxazol-5′-yl)benzo[5,6]coumarin were prepared via condensation of 3-(2′-formyl-1′-chlorovinyl)benzo[5,6] coumarin with hydrazine derivatives or hydroxylamine.Reaction of 3-[1′(1′H)-pyrazol-5′-yl]benzo[5,6]coumarin with alkyl halides,olefinic compunds or acid chlorides are described. 相似文献
13.
In this paper 1,3-dipolar cycloaddition reaction has been studied. An efficient synthesis of 4′-[3-methyl-5-thioxo-1H-1,2,4-triazol-4(5H)-yl]-2′,5′-diphenyl-2′,4′-dihydro spiro(indolin-3,3′[1,2,4]triazol)-2-one derivatives using triethylamine in MeCN at room temperature is reported. The structures of the obtained compounds were confirmed by means of elemental analysis, MS and spectral (IR, 1H, and 13C NMR) methods. 相似文献
14.
El-Barbary A. A. El-Brollosy N. R. Pedersen E. B. Nielsen C. 《Monatshefte für Chemie / Chemical Monthly》1995,126(5):593-600
Summary Thieno[2,3-d]pyrimidine-2,4(1H,3H)-dione (4) was silylated and condensed with methyl 5-azido-2,5-dideoxy-3-O-(4-methylbenzoyl)-D-erythro-pentofuranoside (2) in the presence ofTMS triflate to afford the corresponding protected nucleoside6 and acyclic nucleoside7. Deprotection of6 with MeONa/MeOH at room temperature gave 1-(5-azido-2,5-dideoxy--D-erythro-pentofuranosyl)-thieno[2,3-d]pyrimidine-2,4(1H,3H)-dione (8) and the corresponding anomer9, whereas compound7 yielded 5-azido-2,5-dideoxy-1-(2,4-dioxo-1,2,3,4-tetrahydrothieno[2,3-d]pyrimidin-1-yl)-1-O-methyl-D-erythro-pentitol (10) under the same reaction conditions. 1-(5-Amino-2,5-dideoxy--D-erythro-pentofuranosyl)thieno[2,3-d]pyrimidine-2,4(1H,3H)-dione (11) was obtained on treating9 with Ph3P in pyridine followed by hyrolysis with NH4OH. The anomeric nucleosides14 and15 and the corresponding acyclic nucleoside16 were obtained when4 was trimethylsilylated and condensed with methyl 2-deoxy-3,5-di-O-(4-methylbenzoyl)-D-erythro-pentofuranoside (3) followed by deprotection with MeONa in MeOH. Compounds8 and9 were also obtained when the anomeric mixture14/15 was treated with a mixture of NaN3, Ph3P, and CBr4 in dryDMF at room temperature.On leave from Chemistry Department, Faculty of Science, Tanta University, Tanta, Egypt 相似文献
15.
Timokhina L. V. Sokol’nikova O. V. Kanitskaya L. V. Voronkov M. G. 《Russian Journal of Organic Chemistry》2009,45(3):466-467
Russian Journal of Organic Chemistry - 相似文献
16.
17.
B. Glöckner 《Monatshefte für Chemie / Chemical Monthly》1949,80(4):489-492
Ohne ZusammenfassungMit 1 Abbildung 相似文献
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19.
YU Zhao-Lian LI Sen-Lan GUO Jin-Bo CHEN Qing-Hua② 《结构化学》2005,24(1):94-98
1INTRODUCTIONThecyclopropane-containingnaturalproductshavereceivedconsiderableattentionassynthetictar-getsastheincorporationofrigidifiedcyclopropylmotifintobioactiveanaloguescanleadtoconfor-mablyconstrainedmolecules[1,.Suchmodifica-2]tionsareexpectedtohavesignificanteffectsonbio-activitieswithconcomitantmedicalimplications.Des-pitethegreatadvancesinthisfield,theefficientsyn-thesisofspiro-cyclopropanecompoundsstillremainsaconsiderablechallenge.Particularnoticeisthede-ficiencyinthepreviousm… 相似文献
20.
V. A. Samsonov Yu. V. Gatilov V. A. Savel’ev S. S. Baranova 《Russian Journal of Organic Chemistry》2012,48(3):399-410
Reactions of 5-nitrospiro[benzimidazole-2,1′-cyclohexane] 1,3-dioxide with aliphatic amines and sodium hydroxide resulted
in removal of one N-oxide oxygen atom and formation of 4-alkylamino- or 4-hydroxy-substituted 5-nitrospiro[benzimidazole-2,1′-cyclohexane] 1-oxides,
respectively. The title compound reacted with ammonia and methylamine in the presence of MnO2 with conservation of both N-oxide moieties, and the products were 4-amino- and 4-methylamino-5-nitrospiro[benzimidazole-2,1′-cyclohexane] 1,3-dioxides.
The reactions with aromatic amines were accompanied by removal of both N-oxide oxygen atoms with formation of N-aryl-5-nitrospiro[benzimidazole-2,1′-cyclohexane]-4-amines. In the reactions of 5-nitrospiro-[benzimidazole-2,1′-cyclohexane]
1,3-dioxide with sodium azide and aromatic amine hydrochlorides nucleophilic replacement of the 5-nitro group by azido or
arylamino occurred, in the first case both N-oxide fragments being conserved. The reactions with aromatic amine hydrochlorides afforded N-aryl-5-nitrospiro[benzimidazole-2,1′-cyclohexan]-4-amine 1-oxides. Treatment of 5-nitrospiro[benzimidazole-2,1′-cyclohexane]
1,3-dioxide with sodium cyanide led to the formation of 5-oxo-3,5-dihydrospiro[benzimidazole-2,1′-cyclohexane]-4-carbonitrile
1-oxide. 相似文献