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21.
Five differently substituted phthalimide nucleosides were studied by NMR spectroscopic techniques for their ability to recognize and bind a cytosine–guanosine (CG) Watson–Crick base pair in CD2Cl2. Whereas only rather weak binding was observed for analogs with an amino, acetamido, or benzamido substituent, strong binding was observed with the analogs carrying an ureido and n‐butyl ureido residue. 2D NOE measurements at low temperatures confirm the proposed binding mode for the high‐affinity ligands but indicate binding interactions for the weakly bound analogs different from the expected geometry. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
22.
G Bocelli 《Pramana》1991,36(6):589-593
C15H11NO2, Mr 237.3, monoclinic, space groupC c, a=8.539(2),b=19.865(4),c=7.599(2)?,β=111.44(2)°,V=1199.8 ?3,Z=4,D c=1.31 gcm−3,λ(CuKα)=1.5418 ?,μ=6.74cm−1,F(000)=496, room temperature. The structure was solved by direct methods with SHELX-86 and refined down to agreement valueR=0.046 for 1117 reflections above 2σ(I). The angle between the plane of the phthalimide group, which shows a little bent [1.2(2)°] between its two rings, and the tolyl group is 56.1(1)°. The packing of the molecules is stabilized by van der Waal’s forces only. Part XXVIII: Bocelli and Rizzoli (1990)  相似文献   
23.
A series of N-substituted phthalimides have been prepared in an effort to explore synthetic variants of the Nefkens’ reagent. Three N-acylphthalimides [R = –CH3, –CH2CH3, and –C(CH3)3] were prepared and employed for the protection of a series of representative amines. In addition, an N-methanesulfonylphthalimide and N-(diethylphosphoryl)phthalimide were also prepared. It was determined that among the phthalimides that were prepared N-propanoylphthalimide was the most effective reagent for the protection reaction.  相似文献   
24.
Radical oligomerization of N‐phenylmaleimide (NPMI) was performed in benzylic hydrocarbons as the solvent. The thermally induced oligomerization occurred only above 130 °C, with the initiation attributed to autoxidation of benzylic hydrocarbons as well as formation and dissociation of charge‐transfer complexes between benzylic hydrocarbons and maleimides. The end‐group analysis on oligo(N‐ethylmaleimide) prepared under similar conditions confirmed that the chain transfer to benzylic hydrocarbons was the primary fashion in forming oligomeric chains, and radical telomerization underlaid the oligomerization with benzylic hydrocarbons as both the solvent, the initiator and the telogen. CoII/N‐hydroxyphthalimide (NHPI) pairs could catalyze the telomerization at 110 °C. In such a catalytic process, CoII‐based oxidative complexes oxidized benzylic hydrocarbons and NHPI into benzylic radicals and phthalimide N‐oxyl (PINO), and benzylic hydrocarbons underwent hydrogen atom transfer (HAT) to PINO. Oligo(NPMI)s were formed via HAT with benzylic hydrocarbons and NHPI. These oligo(NPMI)s exhibited fluorescent properties with excitation at 270–350 nm and 400–550 nm and emission at 530–750 nm. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 3846–3857  相似文献   
25.
王朝阳  宋光伟  朱锦桃 《有机化学》2009,29(7):1142-1146
报道了以邻苯二甲酰亚胺作亲核试剂, 在手性催化剂salen(Co)(OAc)作用下动力学拆分外消旋末端环氧化物, 得到较高光学活性的末端环氧化物, 同时也得到了中等光学活性的N-保护的1,2-胺醇化合物. 该拆分反应所用催化剂易得, 且原料价廉, 反应无需惰性气体保护.  相似文献   
26.
Novel phthalimides ( 1 , 2 , 3 ) possessing variability of cyclic amines have been synthesized and characterized by analytical and spectroscopic techniques. Phthalimide 1 and 2 crystallized in a triclinic system with space group Pī; however, an orthorhombic system with a chiral space group of P212121 was observed for 3 possessing piperidine cyclic amine. The hydrogen atoms attached to the central chiral carbon were oriented anti to each other resulting in minimum steric repulsion. The occurrence of C–H···O hydrogen bonds in 1 , 2 , 3 enabled the building of several supramolecular structures. Hyperpolarizability 197.6096 Debye Å2 calculated for 1 was found to be higher than the hyperpolarizabilities, 138.0836 and 165.2521 Debye Å2 measured for 2 and 3 , respectively. Subsequently, phthalimides ( 1 , 2 , 3 ) were assessed for second harmonic generation (SHG) response, and a negligible response was recorded for 1 and 2 ; however, 3 showed a significant response of 14.2 mV. In addition to acentric structure, helical structural motifs identified in 3 could be responsible for its enhanced SHG response. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
27.
<正>An efficient and mild method for the direct conversion of alcohols into N-alkylphthalimides using 2,4,6-trichloro-1,3,5-triazine and dimethylformamide was described.The reaction was preceded via(alcoxymethylene) dimethylammonium chloride intermediate and produced corresponding N-alkylphthalimides in good-to-excellent yields.  相似文献   
28.
烷基二醇与三丁基锡碘甲烷反应得三丁基锡甲氧基烷基醇(2a~2 e);2(或其衍生物)与邻苯二甲酰亚胺反应合成了N-[ω-(三丁基锡甲氧基)烷基]邻苯二甲酰亚胺(5a~5 e),其结构经NMR和MS表征。5在光诱导下,由单电子转移引发,经分子内自由基偶合,高产率(85%~99%)地获得可控制反应位置的大环化合物。  相似文献   
29.
The free radical polymerization of N-(p-vinylbenzyl)phthalimide (VBP) “initiated” with the adduct of 2-benzoyloxy-1-phenylethyl and TEMPO (BS-TEMPO) or TEMPO-terminated polystyrene (PS-TEMPO) in N,N-dimethylformamide (DMF) at 125 °C was found to proceed in a living fashion, providing low-polydispersity PVBP and block copolymers of the type PS-b-PVBA, where TEMPO is 2,2,6,6-tetramethylpiperidinyl-1-oxy. Unlike TEMPO-mediated styrene polymerization, the polymerization rate slightly but distinctly depended on the adduct concentration, which was interpretable as a pre-stationary behavior. The hydrolysis of those polymers gave poly(p-aminomethylstyrene) (PAMS) and PS-b-PAMS, and further treatment of the block copolymer with hydrogen chloride provided an amphiphilic block copolymer. The polymeric amphiphile was used as an emulsifier in emulsion polymerization to produce a positively charged polymeric microsphere.  相似文献   
30.
Synthesis of N-alkyl phthalimides and N-alkyl succinimides through alkylation of potassium phthalimide and potassium succinimide in dry media catalyzed by phase-transfer catalyst under microwave irradiation will be reported. The reactions were with fairly high yield.  相似文献   
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