- Studies of NMR Chemical Shifts of Chalcone Derivatives of Five-membered Monoheterocycles and Determination of Aromaticity Indices
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A series of the chalcone derivatives of the five-membered monoheterocyclic compounds, (E)-1-aryl-3-heteroarylpropen-1-ones, were prepared by aldol condensation of the corresponding aldehydes of thiophene, pyrrole, and furan with m- and p-substituted acetophenones. Similar condensation of the acetyl compounds of the heterocycles with m- and p-substituted benzaldehydes gave another series of the chalcone derivatives, (E)-1-heteroaryl-3-arylpropen-1-ones. The 13C chemical shift values (δC) of the chalcone derivatives were determined in order to find if they correlated with the Hammett σ values. A good correlation, especially for the β-C for both series, was found for the 13C chemical shift values (δC) of the chalcone derivatives with the Hammett σ values. The chemical shift values of the β-C of the heterocyclic compounds were plotted against those of the benzene derivatives. The resulting slopes were found to be close to the values of the aromaticity indices.
- Jeong, Eun Jeong,Lee, In-Sook Han
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p. 668 - 673
(2019/07/12)
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- Synthesis and anti-bacterial activity of some heterocyclic chalcone derivatives bearing thiofuran, furan, and quinoline moieties
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36 Novel heterocyclic chalcone derivatives were synthesized and tested for their anti-bacterial activity. Some compounds presented good anti-microbial activities against Gram-positive bacteria (including the multidrug-resistant clinical isolates). This cl
- Zheng, Chang-Ji,Jiang, Sheng-Ming,Chen, Zhen-Hua,Ye, Bai-Jun,Piao, Hu-Ri
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experimental part
p. 689 - 695
(2012/06/01)
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- Studies on the nuclear magnetic resonance spectra of (E)-1-Aryl-3-(2- and 3-thienyl)-2-propenones and unique observation of 4J and 5J coupling in their 1H-1H COSY
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1H and 13C NMR spectra of series of (E)-1-aryl-(2- and 3-thienyl)-2-propenones, that are aldol condensation products between 2- and 3-thiophenecarbaldehydes and m- and p-substituted acetophenones, were examined to make complete assig
- Han Lee, In-Sook,Jeon, Hyun Ju,Lee, Chang Kiu
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scheme or table
p. 687 - 692
(2011/12/03)
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- Substituent chemical shifts of (E)-1-aryl-3-thienylpropen-1-ones
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Substituent chemical shifts were examined for the 2- and 3-thiophene derivatives of chalcone and compared to the thiophene series of derivatives with the phenyl series. The chemical shift values for the α-carbons of the enones showed and inverse correlation with the Hammett σ values, but the correlation coefficients were moderate (r = 0.836 - 0.878). On the other hand, the β-carbons showed a normal correlation with excellent correlation coefficients (r = 0.994). The absolute magnitude of the p values for the α-carbon are about half of those of the β-carbon. The observation may be the result of a through-space transition of the electronic effect of the substituents in addition to the through bond transition.
- Lee, In-Sook Han,Jeon, Hyun Ju,Yu, Ji Sook,Lee, Chang Kiu
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experimental part
p. 1689 - 1694
(2010/10/21)
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- Studies of Substituent Effects by Carbon-13 NMR Spectroscopy. Thiophene and Furan Chalcone Analogues
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13C NMR spectra of 39 thiophene and furan chalcone analogues in CDCl3 solutions are reported.The effect of substituents on the 13C chemical shifts in the phenyl and in the 5-membered rings is discussed. 13C NMR shifts are correlated with Hammett parameter
- Musumarra, Giuseppe,Ballistreri, Francesco P.
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p. 384 - 391
(2007/10/02)
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