Structure Elucidation of the Adducts Formed by Fjord Region Dibenzo[a,l]pyrene-11,12-dihydrodiol 13,14-Epoxides with Deoxyguanosine
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- 作者：Kai-Ming Li ; Mathai George ; Michael L. Gross ; Cheng-Huang Lin ; Ryszard Jankowiak ; Gerald J. Small ; Albrecht Seidel ; Heiko Kroth ; Eleanor G. Rogan ; and Ercole L. Cavalieri
- 刊名：Chemical Research in Toxicology
- 出版年：1999
- 出版时间：September 1999
- 年：1999
- 卷：12
- 期：9
- 页码：778 - 788
- 全文大小：328K
- 年卷期：v.12,no.9(September 1999)
- ISSN：1520-5010
文摘
(±)-anti-Dibenzo[a,l]pyrene-11,12-dihydrodiol 13,14-epoxide {(±)-anti-DB[a,l]PDE} was reacted with deoxyguanosine (dG) in dimethylformamide at 100 
C for 30 min, and two sets ofadducts were isolated: a mixture of (±)-anti-cis- & -trans-N2dG (43%) and a mixture of (±)-anti-cis- & -trans-N7Gua (45%). Both are mixtures of four stereoisomers that cannot beseparated by HPLC. Similarly, (±)-syn-DB[a,l]PDE was reacted with dG under the sameconditions, and (±)-syn-cis- & -trans-N2dG (38%) and (±)-syn-cis- & -trans-N7Gua (59%) wereobtained. The structures of the adducts were determined by a combination of NMR and fastatom bombardment mass spectrometry. By reacting (-)-anti-DB[a,l]PDE or (+)-syn-DB[a,l]PDE with dG under the same conditions, however, optically pure N2dG and N7Gua isomerswere obtained: (-)-anti-cis-N2dG (12%), (-)-anti-trans-N2dG (17%), (-)-anti-trans-N7Gua(43%), (+)-syn-cis-N2dG (7%), (+)-syn-trans-N2dG (3%), (+)-syn-cis-N7Gua (36%), and (+)-syn-trans-N7Gua (22%). The structures of the optically pure adducts were assigned by NMR. syn-and anti-DB[a,l]PDE-N2dG adducts can be distinguished by fluorescence line-narrowingspectroscopy (FLNS). Moreover, distinction between cis- and trans-stereochemistry of theadducts is also straightforward by FLNS, because the FLN spectra for the four DB[a,l]PDE-N2dG adducts, anti-cis, anti-trans, syn-cis, and syn-trans, are spectroscopically unique.
C for 30 min, and two sets ofadducts were isolated: a mixture of (±)-anti-cis- & -trans-N2dG (43%) and a mixture of (±)-anti-cis- & -trans-N7Gua (45%). Both are mixtures of four stereoisomers that cannot beseparated by HPLC. Similarly, (±)-syn-DB[a,l]PDE was reacted with dG under the sameconditions, and (±)-syn-cis- & -trans-N2dG (38%) and (±)-syn-cis- & -trans-N7Gua (59%) wereobtained. The structures of the adducts were determined by a combination of NMR and fastatom bombardment mass spectrometry. By reacting (-)-anti-DB[a,l]PDE or (+)-syn-DB[a,l]PDE with dG under the same conditions, however, optically pure N2dG and N7Gua isomerswere obtained: (-)-anti-cis-N2dG (12%), (-)-anti-trans-N2dG (17%), (-)-anti-trans-N7Gua(43%), (+)-syn-cis-N2dG (7%), (+)-syn-trans-N2dG (3%), (+)-syn-cis-N7Gua (36%), and (+)-syn-trans-N7Gua (22%). The structures of the optically pure adducts were assigned by NMR. syn-and anti-DB[a,l]PDE-N2dG adducts can be distinguished by fluorescence line-narrowingspectroscopy (FLNS). Moreover, distinction between cis- and trans-stereochemistry of theadducts is also straightforward by FLNS, because the FLN spectra for the four DB[a,l]PDE-N2dG adducts, anti-cis, anti-trans, syn-cis, and syn-trans, are spectroscopically unique.