Proton Nuclear Magnetic Relaxation : An Application to the Study of the Conformation and Configuration of Saframycin A

Proton nuclear magnetic resonance (1H-NMR) relaxation of saframycin A in C6D6 has been studied. Quantitative analysis of spin-lattice relaxation times and nuclear Overhauser effect (NOE) factors allowed the determination of the α-axial orientation of the nitrile group at C21, (previously unknown). The conformation of saframycin A in C6D6, which was deduced from the relaxation data, was compared with that of saframycin C in the crystal state.