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THE EFFECT OF SUBSTITUENTS ON PHTHALOCYANINE PHOTOCYTOTOXICITY
Photochemistry and Photobiology, 1987AbstractPhthalocyanine (Pc) dyes are a class of photosensitizers that are being considered for use in the photodynamic therapy of cancer. A final choice for the most useful drug demands phototoxicity screening of various structurally related Pc dyes, such as those with different substituents at the peripheral benzene rings.
I, Rosenthal +5 more
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The Substituent Effect. 15. The LSFE Treatment of Substituent Effects on Basicities of Pyridines
Bulletin of the Chemical Society of Japan, 1980Abstract The relative dissociation constants of meta and para substituted pyridinium ions in H2O at 25 °C were collected from a number of sources. To understand the actual substituent effects with a combination of inductive (I) and pi-electronic (Pi) effect components, the LSFE equation has been employed statistically for each of the ...
Masami Sawada +4 more
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Substituent Effects on the Cooperativity of Halogen Bonding
The Journal of Physical Chemistry A, 2013DFT calculations (B97-1) with the 6-31+G(d,p)-LanL2DZdp basis set were used to analyze the intermolecular interactions in 4-Z-Py···XCN···XCN triads (Z = H, F, OH, OCH3, CH3, NH2, NO2, and CN; Py = pyridine; and X = Cl and Br) that are connected by halogen-bond interactions. To understand the properties of the systems better, the corresponding dyads are
Solimannejad, Mohammad +2 more
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Substituent effects of halopyridines
Journal of Molecular Structure, 2008Abstract The electronic structures of a number of halopyridines were measured by HeI photoelectron (PE) spectroscopy. Combined the empirical arguments and theoretical methods, the observed PE bands were interpreted. The careful analysis of measured π-orbital and halogen lone pair ionization energies enable us to describe substituent effects in terms ...
Chun-Ping Ma, Li Yao, Mao-Fa Ge
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Substituent effects in cyclopolyphosphines
Journal of the Chemical Society, Chemical Communications, 1974For cyclopolyphosphines, (RP)n, a linear relationship which is independent of the ring size, n, exists between the electrochemical reduction potential of the ring and the inductive effect of the pendant organic group.
Timothy J. DuPont +2 more
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Additive Effects of Substituents
Nature, 1950THE present practice of analysing data relating to reaction-rates in solution in terms of the parameters of the modified Arrhenius equation, has led to a more complete understanding of the way in which polar substituents affect chemical reactivity by focusing attention on the fact
BRYNMOR JONES, J. ROBINSON
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Collection of Czechoslovak Chemical Communications, 1980
Various quantum chemical approaches to the problem of transmission of the substituent effect were compared. It was shown that inclusion of the electronic repulsion (field effect) was necessary to give a true picture of differences in ρ constants for reactions of the cis and trans isomers of substituted unsaturated carboxylic acids; the same holds for ...
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Various quantum chemical approaches to the problem of transmission of the substituent effect were compared. It was shown that inclusion of the electronic repulsion (field effect) was necessary to give a true picture of differences in ρ constants for reactions of the cis and trans isomers of substituted unsaturated carboxylic acids; the same holds for ...
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Substituent effects in cyclohexenes
Bulletin of the Academy of Sciences of the USSR Division of Chemical Science, 1980The effects of the C1-CH3 group in the13C spectra of trans-4,5-dimethylcyclohex-4-ene-1,2-dicarboxylic and syn-txans-Δ4-octalin-1,2-dicarboxylic acid and their diesters show the existence in solution of a considerable proportion of the trans-a,a forms of these compounds.
V. A. Denisenko +3 more
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Journal of Physical Organic Chemistry, 1999
A brief description and analysis of the history of and modern situation in the field of inductive effects, methods for its quantitative determination and prospects are presented, including a discussion of the underlying mechanism. Copyright © 1999 John Wiley & Sons, Ltd.
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A brief description and analysis of the history of and modern situation in the field of inductive effects, methods for its quantitative determination and prospects are presented, including a discussion of the underlying mechanism. Copyright © 1999 John Wiley & Sons, Ltd.
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Substituent effects in the napthalene system. [PDF]
Forty-four substituted 2-naphthoic acids, two substituted 1-naphthoic acids and some of their corresponding methyl esters have been synthesized. The substituents are the nitro, cyano, fluoro, chloro, bromo, iodo, methyl, hydroxyl, methoxy, amino and dimethylamino groups.
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