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1.
Four novel derivatives of 2-amino-9-(beta-D-ribofuranosyl)purine (1) were synthesised and fully characterised. When 1 was reacted with chloroacetaldehyde (a), 2-chloropropanal (b), bromomalonaldehyde (c) and a mixture of chloroacetaldehyde + malonaldehyde (d), 3-(beta-D-ribofuranosyl)-imidazo-[1,2a]purine (2), 3-(beta-D-ribofuranosyl)-5-methylimidazo-[1,2a]purine (3), 3-(beta-D-ribofuranosyl)-5-formylimidazo-[1,2a]purine (4) and 9-(beta-D-ribofuranosyl)-2-(3,5-diformyl-4-methyl-1,4-dihydro-1-pyridyl)purine (5) were formed, respectively. The products were isolated, purified by chromatography and characterised by MS, complete NMR assignment as well as fluorescence and UV spectroscopy. The yields of these reactions were moderate (14-20%). The fluorescence properties differed from those of the starting compound and the quantum yields were considerably lower.  相似文献   

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4.
Acyclic, achiral nucleoside derivatives 1b-e of adenine, cytosine, 5-methylcytosine, and guanine, containing a 3-hydroxy-2-(hydroxymethyl)prop-1-enyl group on N-1 or N-9, have been prepared analogously to the previously described thymine derivative 1a. In contrast to the adenine and guanine derivatives, the cytosine derivative 9 was unstable, and was obtained in a low yield due to side reactions. These include cleavage of the propenyl group from the base, and the formation of a bicyclic compound. The thymine derivative, although stable under neutral conditions, likewise underwent a reversible cyclization reaction (Michael addition) in the presence of acids or bases. The 5-methylcytosine derivative was stable under neutral and basic conditions. Four other nucleoside derivatives 26a-d containing a 2,3-dihydroxy-2-(hydroxymethyl)propyl group on N-1 or N-9, three of which are new, have likewise been prepared. All compounds were evaluated as antiviral agents against HIV-1 and HSV-1 but were devoid of antiviral activity.  相似文献   

5.
A method for the synthesis of 1-[ω-(3,3-dialkyldiaziridin-1-yl)alkyl]-3,3-dialkyldiaziridines based on the reaction of ketoxime O-arenesulfonates with alkylenediamines was developed. Diastrereomers (the racemic and meso forms) of 1-[2-(3,3-dimethyldiaziridin-1-yl)ethyl]-3,3-dimethyldiaziridine were isolated. The structure of the meso form was confirmed by X-ray diffraction analysis. Dedicated to Academician V. A. Tartakovsky on his 75th birthday. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1491–1495, August, 2007.  相似文献   

6.
在对甲苯磺酸存在下,采用1,1-二[4-(N,N-二取代氨基)苯基]乙烯(3)和四氯苯酐在乙酸酐溶液中的缩合反应合成了3,3-二{2,2-二[4-(N,N-二取代氨基)苯基]乙烯基}-4,5,6,7-四氯-2-苯并[c]呋喃酮(4),产率89~93%。3由4,4'-二(N,N-二取代氨基)二苯甲酮(1)与甲基碘化镁进行Grignard反应的产物经水解再脱水制得,产率85%~88.5%(以1为基准)。  相似文献   

7.
Poly[3,3-bis(hydroxymethyl)oxetane], PBHMO, was prepared in high molecular weight (ηinh up to 5.2) by polymerizing the trimethylsilylether of 3,3-bis(hydroxymethyl)oxetane with the i-Bu3Al–0.7 H2O cationic catalyst at low temperature, followed by hydrolysis. PBHMO is crystalline, very high melting (314°C) and highly insoluble, much like its analog, cellulose. It is soluble in 75% H2SO4 at 30°C, being 65% converted to the acid sulfate ester; these conditions are useful for viscosity measurement, since the degradation rate is low and at least an order of magnitude less than for cellulose in this solvent. PBHMO can be prepared as oriented films and fibers using the lower melting diacetate (184°C) which can be melt or solution (CHCl3) fabricated and then the oriented forms saponified to oriented PBHMO. BHMO can be directly polymerized to low molecular weight, perhaps somewhat branched, PBHMO (ηinh 0.1) with trifluoromethanesulfonic acid catalyst at room temperature. Poly(3-methyl-3-hydroxymethyloxetane), (PMHMO), prepared in high molecular weight (ηinh up to 3.8) by the same method used for PBHMO, is more soluble and lower melting (165°C) than PBHMO, appears to be atactic and can be compression molded at 195°C to a tough, clear film which is readily oriented. Copolymers of BHMO with MHMO are crystalline over the entire composition range with a linear variation of Tm with composition, a new example of isomorphism in the polymer area.  相似文献   

8.
The reaction of benzimidazoline-2-thione with perfluoro-2-methylpent-2-ene in the presence of triethylamine afforded (2E)-2-(tetrafluoroethylidene)-3,3-bis(trifluoromethyl)-2,3-dihydrothiazolo[3,2-a]benzimidazole whose structure was confirmed by X-ray diffraction analysis. The reaction pathways are discussed.  相似文献   

9.
This article describes the synthesis and the cation-radical polymerization (Scholl reaction) of 1,3-bis[4-(1-naphthoxy) benzoyl] benzene ( 6 ) and 1,4-bis[4-(1-naphthoxy) benzoyl]- benzene ( 7 ) initiated by FeCI3. This polymerization produced poly(ether ether ketone ketone)s (PEEKK) of number average molecular weight (M?n) up to 5400 g/mol. The synthesis of bis[4-(1-naphthoxy) phenyl] methane ( 8 ), 1,3-bis[4-(1-napthoxy) phenylmethyl] benzene ( 9 ), and 1,4-bis[4-(1-naphthoxy) phenylmethyl] benzene ( 10 ) are also described. Polyethers of M?n up to 15400 g/mol at a FeCl3/monomer molar ratio of 2/1 were obtained. An increased polymerizability of the monomers 9 and 10 containing two CH2 groups versus that of the corresponding monomers containing two carbonyl groups ( 6 and 7 ) was observed. This enhanced polymerizability was explained based on the increased nucleophilicity of monomers 9 and 10 .  相似文献   

10.
New procedures were developed for the synthesis of 3,3-bis(hydroxymethyl)oxetane dinitrate (1) by O-nitration of the corresponding glycol (3) or its mononitrate (6), which were prepared by the reactions of 2,2-bis(hydroxymethyl)propane-1,3-diol (pentaerythritol) (2) mono- (4) and dinitrates (5), respectively, with alkali. A new method was devised for the synthesis of compounds 4 and 5 by the reaction of tetraol 2 with concentrated HNO3 in dichloroethane. The structures of compounds 1 and 6 were established by X-ray diffraction analysis.  相似文献   

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The synthesis of four dialkyl and three eyeloalkyl analogs of psilocin (4, R - CH3), a hallucinogenic principle found in certain fungi, is described. The synthetic route involves four transformations starting with 6,7-dihydroindol-4(5H)one: (1).  相似文献   

13.
采用钯催化的碳碳偶合反应合成了9-戊基咔唑-3,6-双-(炔苯基-4-甲酸乙酯)(I).进一步研究了化合物I在四氢呋喃和40%四氢呋喃水溶液中的光物理性质,结果显示,化合物I在40%四氢呋喃水溶液中的紫外吸收峰位置与其四氢呋喃溶液相比没有发生明显移动,它在40%四氢呋喃水溶液中的单光子荧光发射峰出现在453 nm,较其在四氢呋喃溶液的发射有42 nm红移,其荧光量子效率为0.44.用波长为660 nm飞秒激光激发时,化合物I在40%四氢呋喃水溶液中的双光子荧光发射最大峰红移至489 nm,其双光子吸收截面值为251GM,比其在四氢呋喃溶液中的截面(151 GM)增强了60%.  相似文献   

14.
The preparation, isolation, structure determination, and some reactions of the two stereoisomers of 2-iodo-9-oxabicyclo[4.2.1]nonane ( 9 and 10 ) and of 2-iodo-9-oxabicyclo[3.3.1]-nonane ( 11 and 12 ), respectively, are described. Iodine cleavage of the [4.2.1]-iodomercuri compound 3 yielded the iodides 9, 10 , and 11 , and iododemercuration of the [3.3.1]-iodomercuri compound 6 afforded the iodo compounds 9, 11 , and 12 , respectively. Direct treatment of 4-cycloocten-1-ol ( 1 ) with iodine in chloroform resulted in the exclusive formation of the two endo-iodides 9 and 11 . Raney nickel treatment as well as lithium aluminium hydride reduction of each índividual iodo compound 9, 10, 11 , and 12 gave the corresponding unsubstituted 9-oxabicyclononane ( 4 or 8 , respectively) with the unaltered skeleton. No rearrangement products could be observed. An oxonium ion is involved as an intermediate in the reaction of the endo-iodides 9 and 11 with silver acetate leading to an identical mixture of the two acetates 15 and 16 as well as in the isomerization of 9 to 11 .  相似文献   

15.
The synthesis and the mechanism of oxidative polymerization of 2,2-bis[4-(1-naphthoxy)phenyl]propane ( 4 ) and 2,2-bis[4-(1-naphthyl)phenyl]propane ( 9 ) are presented. Both monomers polymerize by two different propagation steps. The first one represents a cation-radical dimerization of the naphthyl groups to dinaphthyl structure. H+[FeCl4]? generated from the first propagation step initiates a transalkylation reaction which provides structural units containing isopropylidenic groups inserted between phenyl and naphthyl, and between two naphthyl groups, respectively. Since the phenyl groups resulted from the second propagation reaction are unreactive in both the oxidative coupling and the transalkylation steps this polymerization reaction leads to polymers with low molecular weights containing phenyl chain ends.  相似文献   

16.
Alkylation of 1,4-bis[2-(pyridin-4-yl)ethenyl]benzene with alkyl p-toluenesulfonates and dimethyl sulfate gave new viologen analogs, 1-alkyl-4-(2-{4-[2-(1-alkylpyridinium-4-yl)ethenyl]phenyl}ethenyl)-pyridinium bis(p-toluenesulfonates) and sulfate. Their derivatives with tetrafluoroborate and tetraphenylborate ions were also obtained. Spectral properties of the synthesized compounds were examined, and their structure was determined by X-ray analysis.  相似文献   

17.
用三苯基氢化锡,三对甲苯基氢化锡作为锡氢化试剂与9-乙炔基-9-芴醇进行反应,合成了2个有机锡化合物:[Z]-2-(三苯基锡基)-1-(9-芴醇)乙烯(1)和[Z]-2-(三对甲苯基锡基)-1-(9-芴醇)乙烯(2)。化合物1和2分别与ICl,Br~2,I~2反应,得到6个有机锡一卤化物,6个有机锡二卤化物和2个有机锡混合卤化物(3-16)。有机锡一碘化物7,13和有机锡二碘化物8,14与KOH乙醇溶液反应,分别得到相应的有机锡氢氧化物17,18和有机锡氧化物19,20。有机锡二碘化物8,14分别与含氮双齿配体1,10-邻菲罗啉(Phen),2,2'-联吡啶(Bipy),8-羟基喹啉(Oxin)反应,得到6个相应的配合物21-26。26个新化合物通过元素分析,锡含量测定,IR,^1HNMR测定对其结构进行了表征。同时测定了化合物2的晶体结构,晶体属单斜晶系,空间群P2~1/c。化合物2是以Sn原子为中心扭曲的四面体构型。  相似文献   

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19.
(±)-trans-1-[2-(Hydroxymethyl)cyclopentylmethyl]uracil ( 1 ) was prepared in two steps and 56% yield from 2-hydroxymethylcyclopentylmethylamine (7) and 3-methoxy-2-propenoylisocyanate ( 6 ). Isocyanate 6 was prepared from methyl 3-methoxy-2-propenoate in four steps and 38% overall yield.  相似文献   

20.
Solid potassium hydroxide dehydrofluorinates 2,2-bis-(trifluoromethyl)-3,4-difluoro-oxetan to 3-fluoro-4,4-bis-(trifluoromethyl)-2-oxete (59%), 2-pentafluoroethyl-3,4-difluoro-oxetan to 2-tetrafluoroethylidene-3,4-difluoro-oxetan, and r-2-heptafluoro-n-propyl-t-3,t-4-difluoro-oxetan to (Z)-2-hexafluoro-n-propylidene- cis-3,4-difluoro-oxetan. Factors which affect these reactions are discussed.  相似文献   

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