3. A seminal paper on the reaction of singlet oxygen with the DNA base guanine was published by C.S. Foote et al. in 2004, less than two years before his untimely death (J. Am. Chem. Soc. 2004, 126, 16777-16782). Please read this paper and answer the following questions. As an aside, if you like a difficult NMR puzzle, you might enjoy this paper which is a masterpiece of structure determination by NMR. (a) Provide a mechanism for the formation of 8-oxo-G from guanine and singlet oxygen; your class notes may be helpful. (b) The authors found that the 8-oxo-G adduct from singlet oxygen and guanine reacts further to an unusual spiro compound.

student found a bottle of unknown origin in the basement of an "CAUTION—contains С₁H₁O.” No other A old house. The bottle was labelled information was given, but inside the bottle were some white crystals. The student took the bottle to a chemistry laboratory, where she analyzed the crystals with the help of the laboratory staff. C₁2H₁6O reacted with Br₂ in CCl4 adding one mole of Br, and forming C₁₂H₁OB2₂. When a sample of C₁₂H₂O was reacted with O3 followed by Zn/H₂O, two different samples, J and K, were obtained. Compound J had a molecular formula of C.HgO₂, and its NMR is shown below. Compound K had a molecular formula of C₂H₂O, and it could be oxidized to compound L, with a molecular formula of C₂H₂O₂. The IR spectrum of L showed a very wide, strong band centred around 3000 cm*¹. The NMR spectrum of L showed only two different absorptions: a doublet (6H) at 0.9 ppm and a septet (1H) at 3.6 ppm. There was also a singlet (1H) off the scale at 11.8 ppm. students, deduce possible…

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Just #2 please