Various NMR techniques have been used to solve the solution structures of a number of molecules. These include colchinoids, acid catalyzed rearrangement products of deoxoartemisinins, and covalent nucleoside adducts from diol epoxides of polycyclic aromatic hydrocarbons. We have analyzed 500 MHz NMR NOE spectra of a DNA duplex modified at the adenosine residue with a highly carcinogenic diol epoxide metabolite of benzo[a]pyrene. These NOE data in conjunction with computer spectral simulation and structure modeling will be used to determine the solution structure of the modified DNA duplex. In an attempt to gain insight into the mechanism of the formation of the less receptive isomeric nucleosides by purine nucleoside phosphorylase, a number of N-7 isomers of ribo- and deoxyribo-nucleosides have been synthesized and their reaction products in the presence of the enzyme have been monitored by NMR.
