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1.
Strongly dissymmetric circularly polarised (CP) luminescence from small organic molecules could transform a range of technologies, such as display devices. However, highly dissymmetric emission is usually not possible with small organic molecules, which typically give dissymmetric factors of photoluminescence (gPL) less than 10?2. Here we describe an almost 103‐fold chiroptical amplification of a π‐extended superhelicene when embedded in an achiral conjugated polymer matrix. This combination increases the |gPL| of the superhelicene from approximately 3×10?4 in solution to 0.15 in a blend film in the solid‐state. We propose that the amplification arises not simply through a chiral environment effect, but instead due to electrodynamic coupling between the electric and magnetic transition dipoles of the polymer donor and superhelicene acceptor, and subsequent CP Förster resonance energy transfer. We show that this amplification effect holds across several achiral polymer hosts and thus represents a simple and versatile approach to enhance the g‐factors of small organic molecules.  相似文献   

2.
2‐Formylchromones and 3‐formylchromones as the first materials singly reacted with 2‐amino‐5‐mercapto‐1,3,4‐thiadiazole to give the corresponding Schiff bases, which on cyclocondensation with mercapto‐acetic acid in 1,4‐dioxane yielded target compounds named 4‐oxo‐thiazolidines. The structures of all the synthetic compounds were confirmed by elemental analysis and IR, 1H NMR, LC‐MS (ESI) spectral data.  相似文献   

3.
A series of novel pyrazolyl‐substituted 1,3,4‐oxadiazole derivatives ( 4a‐4o ) were prepared by cyclization of the intermediate N′‐((3‐aryl‐l‐phenyl‐pyrazol‐4‐yl)methylene)arylhydrazide with acetic anhydride. The structures of the new compounds were confirmed by IR, 1H NMR, MS and elemental analysis. Furthermore, preliminary bioassay of some of the title compounds indicated that they exhibited moderate inhibition against HIV‐1 PR.  相似文献   

4.
A series of novel pyrazolyl‐substituted 1,3,4‐thiadiazole derivatives ( 6a‐6d, 7a‐7d, 8a‐8d ) were prepared by cyclization of the intermediate 3‐aryl‐l‐phenyl‐pyrazol‐4‐ylformaldehyde 4′‐phenylthiosemicarbazones with 0.5 M ferric chloride solution. The structures of the new compounds were confirmed by IR, 1H NMR and elemental analysis. Simultaneously, the compounds were detected by fluorescence spectrophotometer and had preferable fluorescence activity.  相似文献   

5.
Several 3‐[5‐methyl‐1‐(4‐methylphenyl)‐1,2,3‐triazol‐4‐yl]‐6‐substituted‐1,3,4‐triazolo[3,4‐b]‐1,3,4‐thiadiazoles have been synthesized and the structures of these compounds were established by elemental analysis, MS, IR and 1H NMR spectral data.  相似文献   

6.
A simple and straightforward synthesis of 5,5′‐diamino‐4,4′‐dinitramino‐3,3′‐bi‐1,2,4‐triazole by the selective nitration of 4,4′,5,5′‐tetraamino‐3,3′‐bi‐1,2,4‐triazole is presented. The interaction of the amino and nitramino groups improves the energetic properties of this functionalized bitriazole. For a deeper investigation of these properties, various nitrogen‐rich derivatives were synthesized. The new compounds were investigated and characterized by spectroscopy (1H and 13C NMR, IR, Raman), elemental analysis, mass spectrometry, differential thermal analysis (DTA), X‐ray analysis, and impact and friction sensitivities (IS, FS). X‐ray analyses were performed and deliver insight into structural characteristics with which the stability of the compounds can be explained. The standard enthalpies of formation were calculated for all compounds at the CBS‐4M level of theory, revealing highly positive heats of formation. The energetic performance of the new molecules was predicted with the EXPLO5 V6.02 computer. A small‐scale shock reactivity test (SSRT) and a toxicity test gave a first impression of the performance and toxicity of selective compounds.  相似文献   

7.
15‐Cyano‐12‐oxopentadecano‐15‐lactone was synthesized in 59% total yield starting from 2‐nitrocyclododecanone by Michael addition to acrylaldehyde, followed by reaction with trimethylsilylcyanide, hydrolysis, ring‐expansion, and Nef reaction. A two‐step, one‐pot synthesis of intermediate 2‐hydroxy‐4‐(1‐nitro‐2‐oxycyclododecyl)butanenitrile from 3‐(1‐nitro‐2‐oxocyclododecyl)propanal was developed and the conditions for the Nef reaction were studied. 15‐Cyano‐12‐oxopentadecano‐15‐lactam was synthesized in 40% total yield starting from 2‐nitrocyclododecanone by Michael addition to acrylaldehyde, followed by Strecker reaction, ring‐expansion, and Nef reaction. The conditions for the Strecker and Nef reactions were studied. The structures of the target compounds, intermediates, and by‐product were characterized by IR, 1H‐ and 13C‐NMR, and elemental analysis or MS.  相似文献   

8.
溴化(a-噻吩甲酰基)甲基三苯鉮1与3-取代苯甲叉基-2,4-戊二酮 2以碳酸钾为碱,在苯中55℃条件下反应,可以较好的收率、高立体选择性地生成反-2-(a-噻吩甲酰基)-3-取代苯基-4-乙氧羰基-5-甲基-2,3-二氢呋喃3。产物结构均经波谱予以确定。本文还提出了生成产物的可能机理。  相似文献   

9.
A series of 2‐amino‐7‐methoxy‐4‐aryl‐4H‐chromene‐3‐carbonitrile compounds 2 were obtained by condensation of 3‐methoxyphenol with β‐dicyanostyrenes 1 in absolute ethanol containing piperidine. The intermediate enamines 3 were prepared by compounds 2 with 5‐substituted‐1,3‐cyclohexanedione using p‐toluenesuflonic acid (TsOH) as catalyst. The title compounds 11‐amino‐3‐methoxy‐8‐substituted‐12‐aryl‐8,9‐dihydro‐7H‐chromeno[2,3‐b]quinolin‐10(12H)‐one 4 were synthesized by cyclization of the intermediate enamines 3 in THF with K2CO3 /Cu2Cl2 as catalyst. The structures of all compounds were characterized by elemental analysis, IR, MS, and 1H NMR spectra. The crystal structure of compound 4i was determined by single‐crystal X‐ray diffraction analysis.  相似文献   

10.
(2R,4S,5S)‐(+)‐5‐(2,2‐Dichloroacetamido)‐4‐(4‐nitrophenyl)‐2‐aryl‐1,3‐dioxanes 3–8 were synthesized with high diastereoselectivity and good yields. The structures of acetals were determined and the configurations were confirmed by 2D‐NMR (NOESY) and X‐ray crystallographic analysis.  相似文献   

11.
A new series of 2‐aryl‐5‐((2‐arylthiazol‐4‐yl)methyl)‐1,3,4‐oxadiazole derivatives was synthesized by condensation of 2‐(2‐substituted thiazol‐4‐yl)acetohydrazide with aryl aldehydes followed by oxidative cyclocondensation using iodobenzene diacetate. The structure of synthesized compounds was characterized by IR, NMR, and mass analysis. All the newly synthesized compounds were evaluated for their in vitro antimicrobial activity. Some of the compounds showed moderate antimicrobial activity.  相似文献   

12.
Condensation of mesito­nitrile oxide with 1,7‐di­methyl‐5‐phenyl‐2,3‐di­hydro‐1H‐1,4‐diazepine leads to two cycloadducts (I) and (II). The structure and stereochemistry of the dicyclo­adduct (II) was established by X‐ray crystallographic analysis.  相似文献   

13.
A series of 1,3‐dithiol‐2‐one derivatives via [4 + 2] Diels–Alder cycloaddition reaction of 4,5‐bis(dibromomethyl)‐1,3‐dithiol‐2‐one with vinyl‐substituted compounds have been synthesized. Structures of all the newly synthesized compounds are well supported by spectral data such as 1H‐NMR, MS, and elemental analysis. The structures of IVf and IVg have been analyzed by X‐ray crystallography.  相似文献   

14.
A series of novel isoxazole, dihydropyrazolone, and tetrahydropyridine derivatives were synthesized by the reaction of corresponding ethyl 1‐substituted aryl‐2‐methyl‐4‐oxo‐1,4,5,6‐tetrahydropyridine‐3‐carboxylates with different hydrazines and hydroxylamine. Reaction of tetrahydropyridone with N ,N‐dimethylformamide dimethyl acetal provided 1‐(5‐chloro‐2‐methylphenyl)‐2‐[2‐(dimethylamino)ethenyl]‐4‐oxo‐1,4,5,6‐tetrahydropyridine‐3‐carboxylate, which was cyclized into a bicyclic compound on treatment with ammonium acetate. The structures of all synthesized compounds were confirmed by IR, 1H NMR, and 13C NMR spectroscopy data. The structure of 5‐(5‐chloro‐2‐methylphenyl)‐4‐methyl‐2‐phenyl‐2,5,6,7‐tetrahydro‐3H‐pyrazolo[4,3‐c]pyridin‐3‐one was unambiguously assigned by means of X‐ray analysis data.  相似文献   

15.
Synthesis, spectral analysis, and antibacterial activity of new coumarin derivatives are described in this paper. Twelve new coumarin derivatives were synthesized in moderate to good yields by the react with 4‐methyl‐6‐(prop‐2‐ynyloxy)‐2H‐chromen‐2‐one ( 3a – c ) and ethyl azide ( 4a – l ) and done by the click reaction to obtained 6‐[(l‐ethyl‐lH‐l,2,3‐triazol‐4‐yl)methoxy]‐4‐methyl‐2H‐chromen‐2‐ones ( 5a – l ). The structures of all the newly synthesized molecules were assigned by elemental analysis and spectral data. The synthesized compounds were screened for their antibacterial activities strains using Cup plate method.  相似文献   

16.
This paper describes a method of preparation of new 3,5′‐dioxo‐2′‐phenyl‐1,3‐dihydrospiro[indene‐2,4′‐[1,3]oxazol]‐1‐yl acetate and its 5‐chloro‐ and bromoderivatives as products of interaction of N‐benzoylglycine (hippuric acid) with corresponding ortho‐formylbenzoic acids. The reaction carried out in acetic anhydride media in the presence of piperidine as catalyst. The novel spirocompounds were purified by column chromatography from multicomponent reaction mixtures. The composition of the spiro‐products was confirmed by C, H, N element analysis. The structure was established by IR, MS, 1H‐ and 13C‐NMR analysis including COSY 1H‐13C experiments.  相似文献   

17.
A series of novel thiazolidinones, that is, 2‐(2‐hydroxy‐5‐((aryl)‐diazenyl)phenyl)‐3‐(4‐hydroxyphenyl)‐thiazolidin‐4‐one, have been synthesized by reaction of various Schiff bases 2‐(4‐hydroxyphenylimino)methyl)‐4‐(aryl)diazenyl)phenol with ethanolic thioglycolic acid. Schiff bases were obtained by the reactions of 4‐amino phenol with 2‐hydroxy‐5‐((aryl)diazenyl)benzaldehyde. The structures of the newly synthesized compounds were confirmed by IR, 1H NMR, mass spectra, and C, H, N elemental analysis. The thiazolidinone derivatives were evaluated for their antibacterial and antifungal activity.  相似文献   

18.
Eighteen novel 2‐(1‐aryl‐5‐methyl‐1,2,3‐triazol‐4‐yl)‐1,3,4‐oxadiazole derivatives and two acylhydrazone intermediate compounds were synthesized by various pathways starting from 1‐aryl‐5‐methyl‐1,2,3‐triazol‐4‐formhydrazide ( 1 ). All products were identified by spectroscopic analysis, and 2‐(1‐aryl‐5‐methyl‐1,2,3‐triazol‐4‐yl)‐5‐benzalthio‐1,3,4‐oxadiazole was further validated by X‐ray crystallography. Results from primary antibacterial activity tests indicated that most of the compounds were effective against E. coli, P. aeruginosa, B. subtilis and S. aureus.  相似文献   

19.
The reaction of 1-phenyl-3-methyl-4-benzoyl-2,5-dihydro-1H-pyrazol-5-one (PMBP) and methyldithiocarbazate (mdtc) in methanol results in formation of a yellow crystalline solid, adduct of 1-phenyl-3-methyl-4benzoyl-2,5-dihydro-lH-pyrazol-5-one and methyldithiocarbazate. When the yellow solids were dissolved in a mixture of methanol and ether (1:4), a red crystal, which is an oxidation product of the former, was obtained by allowing solvent to evaporate for a few days at room temperature. The X-ray analysis of the red crystal indicates that it is a novel disulfide with a special structure like a “U” conformation in the solid state.  相似文献   

20.
Fifteen new ferrocene derivatives containing 1H‐1,2,4‐triazole moiety were synthesized in various yields by the condensation of ferrocenecarboxaldehyde with 1‐aryl‐3‐(1H‐1,2,4‐triazo‐1‐yl)‐propen‐1‐ones in toluene. Their structures have been confirmed by 1H NMR, IR, MS and elemental analysis. In addition, the crystal structure of 4l was determined. The antifungal and plant growth regulatory activities of the title compounds are discussed. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

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