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Bay region PAHs

B[o]P is known as a bay region PAH it has a relatively uncrowded region near the critical aliphatic CIO position that is linked to N2-dG or N6-dA in covalent DNA... [Pg.266]

Figure 4. Plots of -log k0 versus AE eloc/ for diol epoxides. Rates were measured at 25 °C in 1 9 dioxaneit O, ionic strength 0.1 (NaClO ). The numbers following the PAH abbreviation, if given, designate the position of the epoxide ring. If no abbreviation is used, the diol epoxide is at a bay region. (Adapted from Refs. 25 and 30.)... Figure 4. Plots of -log k0 versus AE eloc/ for diol epoxides. Rates were measured at 25 °C in 1 9 dioxaneit O, ionic strength 0.1 (NaClO ). The numbers following the PAH abbreviation, if given, designate the position of the epoxide ring. If no abbreviation is used, the diol epoxide is at a bay region. (Adapted from Refs. 25 and 30.)...
Figure 5. Plots of log rel. mutagenicity toward Sj typhimurium TA 100 and Chinese hamster V79 cells versus AE eioc/3 for PAH diol epoxides-1. Numbers refer to the position of the epoxide the epoxide is at a bay region if the number is not given. (Adapted from Refs. 14, 28, and 29.)... Figure 5. Plots of log rel. mutagenicity toward Sj typhimurium TA 100 and Chinese hamster V79 cells versus AE eioc/3 for PAH diol epoxides-1. Numbers refer to the position of the epoxide the epoxide is at a bay region if the number is not given. (Adapted from Refs. 14, 28, and 29.)...
For the alternant PAH that have been studied extensively, bay-region diol epoxides are important metabolically activated forms. Studies of the chemical and biological activity of a variety of diol epoxides have provided insight into the factors related to reactivity and biological activity. Chemical reactivity, as measured by spontaneous hydrolysis, correlated well with calculated quantum chemical parameters that estimate ir-electron stabilization upon conversion of the epoxide to a benzylic carbocation, provided... [Pg.85]

In 1979, based on our work on methylchrysenes and on literature data on other methylated PAH, we suggested that the structural requirements favoring tumorigenicity of methylated PAH were a bay region... [Pg.92]

Bonds in the "K-region" are usually short (1.34-1.35 A), near in values to that for a pure double bond, while most other C-C bonds in PAHs are in the range 1.36-1.44 A. The second area of interest is the "bay region" (27) which corresponds to the hindered region between the 4- and 5- positions of phenanthrene (the area between CIO and Cll of BP (I) or Cl and C12 of DMBA (II), for example). [Pg.133]

However, such intercalation involves the insertion of a flat molecule, with a ir-electron system, between the ir-electron systems of the bases of DNA. Therefore a buckled molecule and/or a methyl group will not fit well in such an intercalation mode. Thus, since the buckled molecules (with a methyl group in the bay region) are more carcinogenic, we concluded that complete intercalation of the hydrocarbon between the bases of DNA is not a likely mechanism for carcinogenicity, since the less planar molecules are more active in terms of carcinogenic activity. However, as we shall show later, it is possible that the planar portion of the PAH may lie between the bases of DNA in a semi-intercalation mode the methyl groups, if present, probably do not take part in this semi-intercalation. [Pg.143]

These results can now be used to consider what happens when a diol epoxide attacks DNA. The epoxide group will open and trans addition will occur. The product (XXVI) will have the DNA substituted adjacent to the bay region (particularly if it is hindered so that the epoxide group is made more reactive) and will lie axial to the PAH ring system. This means that the plane of the PAH and the alkylated base of DNA must have a perpendicular relationship to each other as indicated in Figure 19. In this Figure those sites in... [Pg.157]


See other pages where Bay region PAHs is mentioned: [Pg.466]    [Pg.177]    [Pg.132]    [Pg.227]    [Pg.267]    [Pg.272]    [Pg.458]    [Pg.464]    [Pg.478]    [Pg.466]    [Pg.177]    [Pg.132]    [Pg.227]    [Pg.267]    [Pg.272]    [Pg.458]    [Pg.464]    [Pg.478]    [Pg.183]    [Pg.187]    [Pg.187]    [Pg.53]    [Pg.69]    [Pg.70]    [Pg.72]    [Pg.74]    [Pg.75]    [Pg.81]    [Pg.83]    [Pg.87]    [Pg.87]    [Pg.87]    [Pg.91]    [Pg.92]    [Pg.93]    [Pg.94]    [Pg.97]    [Pg.103]    [Pg.103]    [Pg.105]    [Pg.107]    [Pg.108]    [Pg.130]    [Pg.133]    [Pg.138]    [Pg.138]    [Pg.141]    [Pg.144]    [Pg.150]   
See also in sourсe #XX -- [ Pg.556 ]




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Bay region

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