Photochemical Generation of Benzyl Cations That Selectively Cross-Link Guanine and Cytosine in DNA.
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ABSTRACT:
SUBMITTER: Wang Y
PROVIDER: S-EPMC5609456 | biostudies-literature | 2016 Jun
REPOSITORIES: biostudies-literature
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Photochemical Generation of Benzyl Cations That Selectively Cross-Link Guanine and Cytosine in DNA.
Wang Yibin Y Liu Shuo S Lin Zechao Z Fan Yukai Y Wang Yinsheng Y Peng Xiaohua X
Organic letters 20160518 11
UV irradiation of several aryl boronates efficiently produced bifunctional benzyl cations that selectively form guanine-cytosine cross-links in DNA. Photoinduced homolysis of the C-Br bond took place with the aryl boronate bromides 3a and 4a, generating free radicals that were oxidized to benzyl cations via electron transfer. However, photoirradiation of the quaternary ammonium salts 3b and 4b led to heterolysis of C-N bond, directly producing benzyl cations. The electron-donating group in the a ...[more]
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