Polycyclic aromatic hydrocarbons structures

McCarthy, J.F., Jimenez, B.D., Barbee, T. (1985) Effect of dissolved humic material on accumulation of polycyclic aromatic hydrocarbons structure-activity relationships. Aqua. Toxicol. 7, 15-24. 

Sovadinova, I., Blaha, L., Janosek, J., Hilscherova, K., Giesy, J.P., Jones, P.D. and Holoubek, I. (2006) Cytotoxicity and aryl hydrocarbon receptor-mediated activity of N-heterocydic polycyclic aromatic hydrocarbons structure-activity relationships. Environmental Toxicology and Chemistry, 25, 1291-1297. 

Sander, L.C. and Wise, S.A., Polycyclic Aromatic Hydrocarbon Structure Index, Natl. Inst. Stand. Technol. Spec. Publ. 922. U.S. Government Printing Office, Washington, 1997. 

Sovadinova I, Blaha L, Janosek J, Hilscherova K, Giesy JP, Jones PD, et al. Cytotoxicity and aryl hydrocarbon receptor-mediated activity of w-heterocyclic polycyclic aromatic hydrocarbons Structure-activity relationships. Environ Toxicol Chem 2006 25 1291-7. 

The substances for which this phenomenon has been observed are invariably polycyclic aromatic hydrocarbon structures. No exciplex formation has been reported in the literature to involve drug molecules, but this remains a possibility in concentrated solution or perhaps in solid-state mixtures. The consequences of exciplex formation are a radiative or nonradiative return to the ground state without chemical change, or electron transfer leading to chemical reaction of the drug, the quencher, or both. Many photoaddition processes are postulated to proceed via exciplex formation with the quencher molecule becoming chemically bound. 

Sander LC, Wise SA. Polycyclic aromatic hydrocarbon structure index, Natl Inst Stand Tech Spec Publ 922. Washington, DC U.S. Government Printing Office 1997. 

In general, the most stable resonance structure for a polycyclic aromatic hydrocarbon is the one with the greatest number of rings that correspond to Kekule formulations of benzene. Naphthalene provides a fairly typical exanple ... 

Benzo[a]pyrene, a molecule with five, fused, hexagonal rings, is among the most carcinogenic of the polycyclic aromatic hydrocarbons (PAHs). Such biological activity may be related to the electronic structure of benzo[a]pyrene and its metabolites. Ionization energies of these molecules therefore have been investigated with photoelectron spectroscopy [28]. 

Polycyclic aromatic hydrocarbons such as fluoranthrene or Cso-fullerene are structures of great interest A straightforward entrance to analogues and partial structure, respectively, has now been developed by de Meijere and coworkers [89], using a combination of a Suzuki and a Heck-type coupling. Thus, reaction of 1,8-dibromophenanthrene 6/1-166 and obromphenylboronic acid 6/1-167 employing 20 mol% of the Pd° catalyst led to 6/1-168 and 6/1-169 in 54% yield as a Id-mixture (Scheme 6/1.45). 

Structures of Carcinogenic and Noncarcinogenic Unsubstituted Polycyclic Aromatic Hydrocarbons... 

Figure 1. Structural formulae of polycyclic aromatic hydrocarbons.

Perminova I, Grechishcheva N, Peterosyan V (1999) Relationships between structure and binding affinity of humic substances for polycyclic aromatic hydrocarbons relevance of molecular descriptors. Environ Sci Technol 33 3781-3787... 

Chen, J., Quan, X., Yan, Y., Yang, F., Peijnenburg, W.J.G.M. (2001) Quantitative structure-property relationship studies on direct photolysis of selected polycyclic aromatic hydrocarbons in atmospheric aerosol. Chemosphere 42, 263-270. 

Govers, H., Ruepert, C., Aiking, H. (1984) Quantitative structure-activity relationships for polycyclic aromatic hydrocarbons Correlation between molecular connectivity, physico-chemical properties, bioconcentration and toxicity in Daphnia pulex. Chemosphere 13, 227-236. 

Ruepert, C., Grinwis, A., Govers, H. (1985) Prediction of partition coefficients of unsubstituted polycyclic aromatic hydrocarbons from C18 chromatographic and structural properties. Chemosphere 14, 279-291. 

Kosian, P.A., E.A. Makynen, P.D. Monson, D.R. Mount, A. Spacie, O.G. Mekenyan, and G.T. Ankley. 1998. Application of toxicity-based fractionation techniques and structure-activity relationship models for the identification of phototoxic polycyclic aromatic hydrocarbons in sediment pore water. Environ. Toxicol. Chem. 17 1021-1033. 

The results suggest that chinoid type structures are the predominant resonance contributors for 88. The IGLO/DZ//3-21G calculated 13C NMR chemical shifts of benzylic monocations 88 correlate reasonably well with the experimentally obtained data. The 13C NMR chemical shifts of the carbocation centers (CH2 carbon) are calculated 10.6-12.5 ppm too deshielded. Similar results were obtained for benzylic dications 89. NMR chemical shifts of arenium ions derived from various classes of polycyclic aromatic hydrocarbons have been calculated using GIAO-DFT methods.103... 

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