N-methylated guanine

It has been shown that, for N -methyl-guanine nucleotides, the intramolecular... 

Another striking feature of the electrode SERS spectra of N-methylated guanines is the dependence of the carbonyl stretching vibration on the site of methylation. In Table 1 it is observed that the SERS spectra of 9-Me-Gua and 3-Me-Gua depart substantially from the spectra of 1-Me-Gua and 7-Me-Gua in the 1700 cm region (the Ce=0 stretching vibration is missing in the 3-Me-Gua and 9-Me-Gua spectra). 

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