Characterization of 5-Hydroxy-8-oxo-7,8-dihydroguanosine in the Photosensitized Oxidation of 8-Oxo-7,8-dihydroguanosine and Its Rearrangement to Spiroiminodihydantoin
详细信息 查看全文
- 作者：Jeremy E. B. McCallum ; Corrie Y. Kuniyoshi ; and Christopher S. Foote
- 刊名：Journal of the American Chemical Society
- 出版年：2004
- 出版时间：December 29, 2004
- 年：2004
- 卷：126
- 期：51
- 页码：16777 - 16782
- 全文大小：162K
- 年卷期：v.126,no.51(December 29, 2004)
- ISSN：1520-5126
文摘
The photosensitized oxidation of 2',3',5'-tris-(O-tert-butyldimethylsilyl)-8-oxo-7,8-dihydroguanosine(8-oxoG) with singlet oxygen was studied by low-temperature NMR. A stable intermediate was characterizedat -60 
C by 13C, 2D NMR HMBC spectra, and chemical shifts calculated by hybrid Hartree-Fock densityfunctional theory which agreed with the structure 5-hydroperoxy-8-oxo-7,8-dihydroguanosine. Reductionof this intermediate at low temperature afforded the corresponding alcohol, the long-postulated 5-hydroxy-8-oxo-7,8-dihydroguanosine, the last intermediate in the formation of spiroiminodihydantoin. Upon warmingto room temperature, this alcohol rearranges to form the spiroiminodihydantoin in good yield within 2 h.
C by 13C, 2D NMR HMBC spectra, and chemical shifts calculated by hybrid Hartree-Fock densityfunctional theory which agreed with the structure 5-hydroperoxy-8-oxo-7,8-dihydroguanosine. Reductionof this intermediate at low temperature afforded the corresponding alcohol, the long-postulated 5-hydroxy-8-oxo-7,8-dihydroguanosine, the last intermediate in the formation of spiroiminodihydantoin. Upon warmingto room temperature, this alcohol rearranges to form the spiroiminodihydantoin in good yield within 2 h.