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61.
62.
Synthesis of 2‐Unsubstituted 1,3‐Selenazoles by Cyclization of Selenoformamide with α‐Bromocarbonyl Compounds 下载免费PDF全文
Harald Below Wolf‐Diethard Pfeiffer Karlheinz Geisler Ashot S. Saghyan Christine Fischer Peter Langer 《Journal of heterocyclic chemistry》2015,52(2):592-596
2‐Unsubstituted 1,3‐selenazoles were prepared by cyclization of selenoformamide with α‐bromoacetophenones. Parent 1,3‐selenazole was prepared by cyclization of selenoformamide with α‐bromoacetaldehyde. 相似文献
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S. K. Amini 《Journal of Structural Chemistry》2015,56(7):1334-1341
The unassigned configurations of a toxic metabolite to mammals extracted from Neosartorya fischeri (fischerin) in C19, C20, C21, and C22 are assigned as R, R, R, and S, respectively. In this assignment, the extensive ab initio calculations followed by chemical shift computations are performed. Computed chemical shifts are correlated to experimental ones in order to find the correct configuration shown here. 相似文献
64.
M. Köse G. Ceyhan S. A. Güngör S. Purtaş V. McKee 《Journal of Structural Chemistry》2015,56(7):1353-1359
A pyridine–diimine compound N,N′-[pyridine-2,6-diyldi(E)methylylidene]bis(4-chloroaniline) is synthesised by a Schiff base condensation of 2,6-diformylpyridine with 4-chloroaniline in methanol and characterised by spectroscopic and analytical techniques. The molecular structure of the compound is determined by the single crystal X-ray diffraction study. The compound crystallizes in the monoclinic crystal system, I2/c space group with unit cell parameters a = 7.0843(12) Å, b = 6.1909(11) Å, c = 36.262(6) Å, β = 91.576(3)°, V = 1589.8(5) Å3 and Z = 4. There is an intermolecular hydrogen bonding in the molecule resulting in a 1D hydrogen bonding chain and these hydrogen bonding chains are linked by Cl…HC(aromatic) interactions forming a 2D network. Crystal packing of the compound is determined by Cl…HC and π–π interactions. In the fluorescence emission spectra in CH3CN, DMF, DMSO and EtOH, the compound shows only one emission maximum. 相似文献
65.
Z. G. Aliev A. G. Korepin T. K. Goncharov V. A. Garanin S. M. Aldoshin 《Journal of Structural Chemistry》2015,56(7):1367-1372
The X-ray crystallographic analysis of 1,7-difluoro-1,1,3,5,7,7-hexanitro-3,5-diazaheptane has been carried out. We have also determined its sensitivity to mechanical actions and a set of calculated and experimental data on explosion characteristics. 相似文献
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M.M. Elseweidy N.N. Younis S.E. Elswefy F.R. Abdallah S.I. El-Dahmy G. Elnagar 《Natural product research》2015,29(10):961-965
The anti-atherogenic potentials of total ginger (Zingiber officinale) extract (TGE) or curcuminoids extracted from turmeric (Curcuma longa), members of family Zingiberaceae, were compared in hypercholesterolaemia. Rabbits were fed either normal or atherogenic diet. The rabbits on atherogenic diet received treatments with TGE or curcumenoids and placebo concurrently for 6 weeks (n = 6). The anti-atherogenic effects of curcuminoids and ginger are mediated via multiple mechanisms. This effect was correlated with their ability to lower cholesteryl ester transfer protein activity. Ginger extract exerted preferential effects on plasma lipids, reverse cholesterol transport, cholesterol synthesis and inflammatory status. Curcuminoids, however, showed superior antioxidant activity. 相似文献