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1.
《Arabian Journal of Chemistry》2022,15(4):103712
Although recent decades have witnessed the synthesis of 1,3,4-thiadiazoles via phosphorus POCl3-promoted cyclization reaction, simultaneous access to 2-amino-1,3,4-thiadiazole and 2-amino-1,3,4-oxadiazole analogs remains unexpected and elusive. Herein, a detailed regiocontrolled synthesis of 2-amino-1,3,4-thiadiazoles in good to high yields with good regioselectivities from readily available thiosemicarbazides using POCl3 was disclosed. Meantime, to establish a comprehensive structure–activity relationship, 2-amino-1,3,4-oxadiazole derivatives as single regioisomers were prepared via EDCI·HCl-triggered cyclization of the thiosemicarbazide intermediates. The in vitro anti-influenza assays proved that the selected compounds with the pyrazine/pyridine ring exhibited certain inhibitory activities against influenza A virus strains A/HK/68 (H3N2) and A/PR/8/34 (H1N1) in MDCK cells. Among them, N-(adamantan-1-yl)-5-(5-(azepan-1-yl)pyrazin-2-yl)-1,3,4-thiadiazol-2-amine (4j) was the most active compound, and exhibited favorable activity with EC50 values of 3.5 μM and 7.5 μM, respectively. In addition, the molecular docking results explained the reason why compound 4j had dual inhibitory activity and revealed the reasonable binding mode of this compound with the M2-S31N and M2-WT ion channels. This compound had the potential to be further developed as an anti-influenza drug. 相似文献
2.
合成了两个侧链含有2,2,6,6-四甲基哌啶-1-氧自由基单元(TEMPO)的1,4-吡咯并吡咯二酮(DPP)共轭聚合物PDPP4T-1和PDPP4T-2,并开展了其半导体性质研究。薄膜场效应晶体管器件测试结果显示,相对于不含TEMPO的聚合物PDPP4T,PDPP4T-1和PDPP4T-2的场效应器件性能有所降低,不过,含TEMPO的聚合物器件性能最高仍达到了2.12cm~2·V~(-1)·s~(-1)。进一步通过原子力显微镜和X射线衍射对TEMPO引入后导致性能降低的可能原因进行了研究。 相似文献
3.
A new method for multi-component synthesis of 1,4-dihydropyridine derivatives (1,4-DHPs) in the presence of meglumine supported on multiwalled carbon nanotubes (MWCNTs@meglumine) as a new heterogeneous, highly efficient and reusable catalyst was investigated. The reaction was performed under ultrasonic irradiation in EtOH at room temperature. A new, highly efficient heterogeneous catalyst, short reaction times, high to excellent yield of products, and safe and clean conditions are the advantages of the presented method. 相似文献
4.
Methylthiouracil‐modified Carbon Paste Electrode as a New Voltammetric Sensor Based on a 1,4‐Michael Addition Reaction for Detection of Dopamine 下载免费PDF全文
M. Arab Chamjangali A. Ahmadi Reskety N. Goudarzi G. Bagherian 《Electroanalysis》2015,27(12):2708-2717
A sensitive dopamine sensor was constructed based on the modified carbon paste electrode with methylthiouracil as a nucleophile in the 1,4‐Michael addition reaction. An ECE mechanism was suggested for dopamine oxidation at the modified electrode. Design of experiments was used in the optimization of variables. Under the optimum conditions, calibration graph was linear in the range of 0.20–15.0 µM with a detection limit of 73 nM. The relative standard deviations (n=5) for 0.50 µM of dopamine was 3.83 %. The selectivity of the sensor was also studied. The developed sensor was applied for analysis of pharmaceutical and biological samples. 相似文献
5.
以苯甲酰丙酮与1,4-丁二胺经缩合反应制得一个新的席夫碱配体——N,N'-双(苯甲酰丙酮)-1,4-丁二胺(L);L与硝酸银经配位反应合成了配合物[Ag_2(L)(NO_3)_2]_n(1),其结构经1H NMR,13C NMR,FT-IR,元素分析和X-射线单晶衍射表征。晶体结构解析表明:1(CCDC∶1 434 692)属单斜晶系,空间群P21/c,晶胞参数a=0.997 81(5)nm,b=0.778 36(4)nm,c=1.704 13(8)nm,β=106.637 0(10),V=1.261 85(11)nm3,Z=2,Dc=1.884 g·cm~(-3),R1=0.020 8,wR_2=0.054 4。1中每个银离子为扭曲四面体的配位构型,分别和相邻配体的γ-碳原子,氧原子及两个NO_3~-的氧原子配位;每个配体作为四齿配体,分别用两端的γ-碳原子,氧原子和四个银离子配位形成1D链结构,1D通过NO_3~-与银离子配位扩展形成3D网状结构。热稳定性研究结果表明:L和1的初始分解温度分别为300℃和200℃。 相似文献
6.
The novel 1,2‐diaryl substituted pyrrolo[3,4‐b]pyridine‐5,7‐diones were selectively synthesized in high yields by the base catalyzed cyclization reaction of 3‐arylamino‐1‐methyl‐1H‐pyrrole‐2,5‐diones with cinnamaldehyde and its derivatives in acetonitrile at room temperature. However, when piperidinium trifluoroacetate was employed as catalyst, the reaction afforded a mixture of 1,2‐diaryl and 1,4‐diaryl substituted pyrrolo[3,4‐b]pyridine‐5,7‐diones in comparable yields. 相似文献
7.
Alan K. Brisdon Abeer M. T. Muneer Robin G. Pritchard 《Acta Crystallographica. Section C, Structural Chemistry》2015,71(10):900-902
Halogen bonding is an intermolecular interaction capable of being used to direct extended structures. Typical halogen‐bonding systems involve a noncovalent interaction between a Lewis base, such as an amine, as an acceptor and a halogen atom of a halofluorocarbon as a donor. Vapour‐phase diffusion of 1,4‐diazabicyclo[2.2.2]octane (DABCO) with 1,2‐dibromotetrafluoroethane results in crystals of the 1:1 adduct, C2Br2F4·C6H12N2, which crystallizes as an infinite one‐dimensional polymeric structure linked by intermolecular N...Br halogen bonds [2.829 (3) Å], which are 0.57 Å shorter than the sum of the van der Waals radii. 相似文献
8.
A stereoselective total synthesis of xyolide, a naturally occurring bioactive nonenolide, has been accomplished. The acid fragment of the molecule has been prepared from D ‐mannitol and the alcohol fragment from (2Z)‐but‐2‐ene‐1,4‐diol. The synthesis involves the coupling of these two fragments using the Yamaguchi esterification protocol, followed by intramolecular ring‐closing methathesis. The diastereoisomeric alcohol fragment has also been utilized in this synthesis by employing the Mitsunobu esterification. 相似文献
9.
10.
由于独特的结构和广泛的应用,多取代环辛四烯及其苯并稠环衍生物的合成方法研究具有重要意义.本文报道了一种钯催化烯基溴化物与芳基溴化物的偶联反应.利用此钯催化的环化自偶联反应,以中等至较好的收率高选择性地从双溴代芳基或烯基化合物合成了多种二苯并[a,e]环辛四烯衍生物. 相似文献